Ordinance No. 18-21 CITY OF TIGARD, OREGON
TIGARD CITY COUNCIL
ORDINANCE NO. 18- 9"/
AN ORDINANCE AMENDING THE TIGARD DEVELOPMENT CODE (TITLE 18) TO ADOPT
NEW FNMA FIRM MAPS AND UPDATED FLOODPLAIN REGULATIONS. PROPOSED TIGARD
DEVELOPMENT CODE CHANGES INCLUDE UPDATED AND NEW DEFINITIONS RELATED
TO FLOODPLAINS BE PLACED WITHIN CHAPTER 18.30 (DEFINITIONS) AND CHAPTER 18.510
(SENSITIVE LANDS); AND 'TEXT AMENDMENTS TO CHAPTER 18.510 (SENSITIVE LANDS)
PROVIDE UPDATED REGULATION RELATING TO MANUFACTURED HOMES AND
REQUIREMENTS FOR NOTFIYING FEMA OF NEW TECHNICAL DATA AND DECLARING AN
EMERGENCY] i-4- cQ
WHEREAS, amendments to the Tigard Community Development Code Chapter 18.510 would adopt the
updated FEMA Flood Insurance Rate Maps ensuring the City's participation in the National Flood Insurance
Program;and
WHEREAS,FEMA reviewed the amendments and approved the changes as being compliant with the National
Flood Insurance Program requirements;and
WHEREAS, FEMA requires the city to adopt the new FIRM maps and updated regulations prior to October
19,2018 to maintain participation in the National Flood Insurance Program;and
WHEREAS, notice was provided to the Department of Land Conservation and Development at least 35 days
prior to the first evidentiary public hearing;and
WHEREAS, notice of the public hearing was given in conformance with Community Development Code
Section 18.710.110;and
WHEREAS, the Tigard Planning Commission held a duly noticed public hearing on September 17, 2018 and
recommended with a unanimous vote that Council approve the proposed code amendment,as amended;and
WHEREAS, the Tigard City Council held a public hearing on October 16, 2018, to consider the proposed
amendments;and
WHEREAS,the Tigard City Council has considered the Planning Commission recommendation;and
WHEREAS, the Tigard City Council has considered the applicable Statewide Planning Goals and Guidelines
adopted under Oregon Revised Statutes Chapter 197; applicable federal and state statutes and regulations;
applicable Metro regulations; applicable Comprehensive Plan Policies; and applicable provisions of the City's
implementing ordinances;and
WHEREAS, the Tigard City Council has determined that the proposed development code amendments are
consistent with the applicable review criteria, and approves amendments to the Tigard Community
Development Code as being in the best interest of the City of Tigard.
NOW,THEREFORE,THE CITY OF TIGARD ORDAINS AS FOLLOWS:
ORDINANCE No. 18-;,2.
Page 1
SECTION 1: Council adopts the findings recommended by the Planning Commission as contained in the
October 16, 2018 Staff Report to the City Council, included as "Exhibit A" to this
Ordinance,as the basis in support of the corresponding code amendments.
SECTION 2: Tigard Community Development Code (Title 18) 18.120 Definitions is amended as shown
in "Exhibit B" and 18.510 Sensitive Lands is amended as shown in "Exhibit C" to this
Ordinance.
SECTION 3: FEMA requires this ordinance be effective by October 19, 2018 in order to allow the city
and its citizens to continue to participate in the National Flood Insurance Program. An
emergency is therefore declared and this ordinance shall be effective immediately upon
passage and signature by the Mayor.
PASSED: By /07477)192031a vote of all Council//members present after being read by
number and title only,this 11 ' ay of O dt'✓ ,2018.
Carol Krager,City Recorder
APPROVED: By Tigard City Council this /6"day of e7i, '‘e.Y ,2018.
Approved as to form. John a. Cook,Mayor
ca.cy
City Attyorney
Date
ORDINANCE No. 18- a,I
Page 2
Exhibit A
Agenda Item: #1
Hearing Date: October 16,2018 Time: 6:30 PM
PLANNING COMMISSION
RECOMMENDATION TO THE
CITY COUNCIL TIGARD
FOR THE CITY OF TIGARD, OREGON
SECTION I. APPLICATION SUMMARY
CASE NAME: REQUIRED FEMA FLOODPLAIN REGULATIONS UPDATE
CASE NO.: Development Code Amendment(DCA) DCA2018-00002
PROPOSAL: The City of Tigard proposes legislative amendments to the Tigard
Development Code (l'DC).The Federal Emergency Management Agency
(FEMA) performed a compliance review of the City's ordinance as it relates
to regulating the special flood hazard area. The proposed changes in Chapter
18.510, Sensitive Lands are required based on this compliance review.
The proposed amendments include:
1. Adoption by reference, the updated Flood Insurance Rate Maps
dated October 19,2018;and
2. Adopt updated floodplain regulations incorporated into TDC
Chapter 18.510, Sensitive Lands, as required by FEMA.
APPLICANT: City of Tigard
13125 SW Hall Blvd.
Tigard, OR 97223
ZONES: Citywide
LOCATION: Citywide
APPLICABLE
REVIEW
CRITERIA: Statewide Planning Goals 1 (Citizen Involvement), 2 (Land Use Planning), 7
(Areas subject to Natural Disasters and Hazards); METRO's Urban Growth
Management Functional Plan Titles 3, and 8; Comprehensive Plan Goals
1.1.2, 2.1.2, 2.1.3, 7.1.7, 7.1.8 and 7.1.9; and Tigard Development Code
Chapters 18.710 and 18.795
SECTION II. PLANNING COMMISSION RECOMMENDATION
REQUIRED FEMA FLOODPLAIN REGULATIONS UPDATE DCA2018-00002
10/16/2018 PUBLIC HEARING,STAFF REPORT TO TME CITY COUNCIL PAGE 1 OF 7
Exhibit A
Planning Commission recommends approval by ordinance of the proposed development code text
amendments (Attachment 1)
SECTION III. BACKGROUND INFORMATION AND PROJECT SUMMARY
Required FEMA Floodplain Regulations Update
The purpose of the Required FEMA Floodplain Regulations Update Project is to update the
Sensitive Lands Chapter (18.510) with the required Federal Emergency Management Agency
(FEMA) requirements and adopt the updated Flood Insurance Rate Maps. A brief summary of the
National Flood Insurance Program and the proposed changes is provided below.
The National Flood Insurance Program (NFIP) is a federal program that was established in 1968
through the passage of the National Flood Insurance Act and administered by FEMA. The
programs allow owners of properties within the Special Flood Hazard Area (SFHA)—also
sometimes described as the 100-year floodplain—to obtain federally-backed insurance for their
properties in jurisdictions that have adopted land use regulations for development in the floodplain.
In addition to providing insurance, the NFIP identifies and maps the Nation's floodplains, known
as the Flood Insurance Rate Map (FIRM) which results from a Flood Insurance Study. The FIRM is
an official map on which FEMA has delineated both the SFHA and other flood zones within a
community. The FIRM is used in determining a jurisdiction's floodplain regulations, whether a
property owner is required to obtain flood insurance as well as the insurance rate.
Floodplain boundaries do not stay constant but rather undergo change over time due to effects of
erosions, development impacts, vegetation removal and other factors. To account for floodplain
boundary changes, FEMA periodically adjusts the SFHA maps used by local jurisdictions. The City
of Tigard does not conduct floodplain inventories and relies on FEMA for the determination of the
SFHA boundary. FEMA periodically amends the regulatory requirement of the NFIP through
updates to the local FIRM and a corresponding Flood Insurance Study (FIS) Report. Prior to
amending the FIRM and/or developing new or revised floodplain requirements as part of the NFIP
updates,FEMA coordinates with local jurisdictions to determine local flood area conditions.
In 2016, the City adopted a new FIS Report, FIRM and revised floodplain regulations. Since the
adoption in 2016, additional areas within Washington County were identified for further study. All
areas that required further study that resulted in map changes are within Washington County, but
outside of Tigard. The City of Tigard must adopt the updated maps with the updated date as a
countywide effort. The FIRM updates must be adopted and effective within 6 months of FEMA's
Letter of Final Determination. On April 19, 2018, FEMA notified the City of Tigard of the final
flood elevation determinations on the FIRM for properties in the City of Tigard within the SFHA.
The letter also stated that no significant changes were made to the flood hazard data on the
preliminary maps within the City of Tigard.
On June 6, 2018, the City was notified that FEMA Region 10 is required to review the current
floodplain to ensure it meets the requirements for participation in the National Flood Insurance
Program. FEMA hired a consulting firm, STARR II, to assist in the review process. The City
received FEMA's review comments on July 30, 2018,which identified additional changes pertaining
to floodplain regulation, not identified by FEMA through the last update in 2016. These changes
are proposed in Attachment 1.
FEMA requires that this ordinance with the proposed text amendments to WC 18.510 and updated
Flood Insurance Rate Maps be adopted and in effect by October 19, 2018 in order for the City of
Tigard to remain a participant in NFIP.
REQUIRED FEMA FLOODPLAIN REGULATIONS UPDATE DCA2018-00002
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Exhibit A
Planning Commission reviewed the proposed amendments at the September 17th, 2018 public
hearing. The only change that resulted from the hearing was to keep the phrase "except in" in
Paragraphs 18.510.020.B.7, 8 and 9, which was shown as stricken in the draft. Planning
Commission also inquired about what would happen if the City did not adopt the proposed
amendments by the October 19, 2018 deadline. Staff stated that the City would be suspended from
participation in the NFIP until the amendments were adopted. No members of the public chose to
attend the hearing or provide written testimony.
Proposed Amendments
Amend the Tigard Development Code Definitions (TDC 18.30) and Sensitive Lands Chapter (TDC
18.510) as proposed:
o Text Amendments to Chapter 18.30 (Definitions) to establish a new definition for
"Flood";
o Text Amendments to Chapter 18.510 (Sensitive Lands) to add new definitions for
"Basement", "Elevated Building", "Manufactured Home Park or Subdivision", and
"Substantial Improvement";
o Text Amendments to Chapter 18.510 (Sensitive Lands) to amend the date of the updated
Flood Insurance Study and accompanying Flood Insurance Rate Map dated October 19,
2018;
o Text Amendments to Chapter 18.510 (Sensitive Lands) to amend regulations for the
manufactured homes;and
o Text Amendments to Chapter 18.775 (Sensitive Lands) to include requirements for
notifying FEMA of new technical data.
SECTION IV. APPLICABLE CRITERIA,FINDINGS AND CONCLUSIONS
STATEWIDE PLANNING GOALS AND GUIDELINES
State planning regulations require cities to adopt and amend Comprehensive Plans and land use
regulations in compliance with the state land use goals. Because the proposed Code Amendments
have a limited scope and the text amendments address only some of the topics in the Statewide
Planning Goals,only applicable Statewide Goals are addressed below.
Statewide Planning Goal 1 —Citizen Involvement:
This goal outlines the citizen involvement requirement for adoption of Comprehensive
Plans and changes to the Comprehensive Plan and implementing documents.
FINDING: This goal has been met by complying with the Tigard Development Code notice
requirements set forth in Section 18.710.110. Notices were sent by US Postal Service on August 23,
2018 to affected government agencies and the latest version of the City's interested parties list. A
notice was published in the Tigard Times newspaper on August 30, 2018. Project information and
documents were published to the City website prior to the public hearing. A minimum of two
Cublic hearings will be held (one before the Planning Commission and the second before the City
ouncil) at which an opportunity for public input is provided.This goal is satisfied.
Statewide Planning Goal 2—Land Use Planning:
This goal outlines the land use planning process and policy framework.
FINDING: The Department of Land Conservation and Development (DLCD) has acknowledged
the City's Comprehensive Plan as being consistent with the statewide planning goals. The
Development Code implements the Comprehensive Plan. The Development Code establishes a
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Exhibit A
process and standards to review changes to the Tigard Development Code in compliance with the
Comprehensive Plan and other applicable state requirements. As discussed within this report, the
applicable Development Code process and standards have been applied to the proposed
amendment. This goal is satisfied.
Statewide PlanningGoal 7—Areas Subject to Natural Disaster:
This goal requires urisdictions to protect development in places subject to natural hazards.
FINDING: The Department of Land Conservation and Development has acknowledged the City's
Comprehensive Plan as being consistent with the statewide planning goals. The proposed text
amendments create a land use control that will buffer land uses and protect development in places
subject to natural hazards. Consistency with the City's Hazard goals and policies are discussed later
in this report under applicable policies of the Tigard Comprehensive Plan. This goal is satisfied.
CONCLUSION: Based on the findings above and the related findings below, staff finds the
proposed code amendments are consistent with applicable Statewide
Planning Goals.
METRO'S URBAN GROWTH MANAGEMENT FUNCTIONAL PLAN
State planning regulations require cities to adopt and amend Comprehensive Plans and land use
regulations in compliance with the state land use goals. Because the proposed Code Amendments
have a limited scope and the text amendments address only some of the topics in the METRO's
Urban Growth Management Functional Plan,only applicable Titles are addressed below.
Title 3—Water Quality and Flood Management:
The intent of this goal is To protect the beneficial water uses and functions and values of
resources within the Water Quality and Flood Management Areas by limiting or mitigating
the impact on these areas from development activities and protecting life and property from
dangers associated with flooding.
FINDING: The proposed amendment will adopt the newly updated FEMA Flood Insurance Rate
Maps,which will allow the City to continue to participate in the National Flood Insurance Program.
The proposed floodplain regulation relating to manufactured homes will provide protection for
development located within natural flood hazard areas. The proposed amendment also includes
updated terminology consistent with state and federal laws.This title is satisfied.
Title 8—Compliance Procedures:
This goal outlines the citizen involvement requirement for adoption of Comprehensive
Plans and changes to the Comprehensive Plan and implementing documents.
FINDING: This title has been met by complying with the Tigard Development Code notice
requirements set forth in Section 18.710.110. Notices were sent by US Postal Service on August 23,
2018 to affected government agencies and the latest version of the City's interested parties list. A
notice was published in the Tigard Times newspaper August 30, 2018. Project information and
documents were published to the City website prior to the public hearing. A minimum of two
public hearings will be held (one before the Planning Commission and the second before the City
Council) at which an opportunity for public input is provided.This title is satisfied.
CONCLUSION: Based on the findings above, staff finds that the proposed code amendment
is consistent with Metro's Urban Growth Management Functional Plan.
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Exhibit A
TIGARD COMPREHENSIVE PLAN
State planning regulations require cities to adopt and amend Comprehensive Plans and land use
regulations in compliance with the state land use goals and consistent with Comprehensive Plan
Goals and Policies. Because the Development Code Amendments have a limited scope and the text
amendments address only some of the topics in the Tigard Comprehensive Plan, only applicable
comprehensive plan goals and associated policies are addressed below.
Comprehensive Plan Goal 1: Citizen Involvement
Policy 1.1.2: The City. shall define and publicize an appropriate role for citizens in each
phase of the land use planning process.
FINDING: This policy has been met by complying with the Tigard Development Code notice
requirements set forth in Section 18.710.110. Notices were sent by US Postal Service on August 23,
2018 to affected government agencies and the latest version of the City's interested parties list. A
notice was published in the Tigard Times newspaper August 30, 2018. Project information and
documents were published to the City website prior to the public hearing. A minimum of two
public hearings will be held (one before the Planning Commission and the second before the City
Council) at which an opportunity for public input is provided. This policy is met.
Comprehensive Plan Goal 2: Land Use Planning
Policy 2.1.2: The City's land use regulations, related plans, and implementing actions shall
be consistent with and implement its Comprehensive Plan.
FINDING: As demonstrated in this staff report, the proposed amendments to the Tigard
Development Code are consistent with the Tigard Comprehensive Plan. This policy is satisfied.
Policy 2.1.3: The City shall coordinate the adoption, amendment, and implementation of its
land use program with other potentially affected jurisdictions and agencies.
FINDING: Copies of the proposed text amendments were sent to affected agencies and were
invited to comment on the proposal and discussed in Section V of this report. Comments
submitted by affected agencies have been incorporated into this report and the proposed
amendments. This policy is satisfied.
Policy 2.1.11: The City shall adopt regulations and standards to protect public safety and
welfare from hazardous conditions related to land use activities.
FINDING: The proposed amendment includes the adoption of FEMA's Flood Insurance Rate
Maps, which will maintain the City's participation in the National Flood Insurance Program and
protect the public welfare for properties located within the SFHA. This policy is satisfied.
Comprehensive Plan Goal 7: Hazards
Policy 7.1.7: The City shall comply with the Federal Emergency Management Agency
(FEMA) flood regulations,which include standards for base flood levels, flood proofing, and
minimum finished floor elevations.
FINDING: The proposed amendments adopt the newly updated FEMA Flood Insurance Rate
Maps, update definitions consistent with federal law, amend regulations for manufactured homes
and provide requirements for notifying FEMA with new technical information. These proposed
amendments are consistent with state and federal laws. This policy is satisfied.
Policy 7.1.8: The City shall prohibit any land form alterations or developments in the 100-
year floodplain which would-result in any rise in elevation of the 100 year floodplain.
FINDING: The proposed amendments adopt the recently updated FEMA Flood Insurance Rate
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Exhibit A
Maps and regulations for development within the SFHA ensuring that development will not result in
any rise in elevation of the 100-year floodplain. This policy is satisfied.
Policy 7.1.9: The City shall not allow land form alterations of development within the 100-
year floodplain outside the zero-foot rise floodway unless:
A. The streamflow capacity of the zero-foot rise and floodway is maintained; and
B. Engineered drawings and/or documentation shows there will be no detrimental
upstream or downstream effects in the floodplain area.
FINDING: The proposed amendments adopt the newly updated FEMA Flood Insurance Rate
Maps and regulations for development within the SFHA ensuring that development will not be
detrimental to the floodplain. This policy is satisfied.
CONCLUSION: Based on the findings above, staff concludes that the proposed code text
amendment is consistent with applicable provisions of the Tigard
Comprehensive Plan.
APPLICABLE PROVISIONS OF THE TIGARD DEVELOPMENT CODE
18.795: Map and Text Amendments
18.795.020 Legislative Amendments
A. Legislative amendments shall be processed through a Legislative procedure, as provided
in Section 18.710.110
FINDING: The proposed amendments are legislative in nature. Therefore, the amendment will be
reviewed under the Legislative procedure. This -procedure requires public hearings by both the
Planning Commission and City Council. This standard is satisfied.
B. Approval considerations. A recommendation or a decision for a legislative amendment
may be based on consideration of the applicable legal requirements. They may, but do
not necessarily include: Oregon Revised Statues, Oregon Administrative Rules, one or
more Statewide Planning Goals, Metro's Urban Growth Management Functional Plan
and any other regional plans.
FINDING: Findings and conclusions are provided in this staff report for the applicable listed
criteria on which the recommendation by the Commission and the decision by the Council shall be
based. This standard is satisfied.
CONCLUSION: Based on the findings above, staff concludes that the proposed code text
amendment is consistent with applicable provisions of the Tigard
Development Code.
SUMMARY
CONCLUSION: As shown in the findings above, staff concludes that the proposed
amendments are consistent with the applicable Statewide Planning Goals;
METRO's Urban Growth Management Functional Plan; applicable
Comprehensive Plan goals and policies, and the applicable provisions of the
City's implementing ordinances.
SECTION V. AGENCY COMMENTS
City of Portland, City of Beaverton, City of Durham, City of Lake Oswego, City of
Tualatin, Cityof King Ci Washington County,METR , ODOT, DLCD, DEQ, ODFW
ODept of Geo. &Mineral Ind., CWS, Tri Met, Comcast, Frontier, NW Natural, PGE,,
REQUIRED FEMA FLOODPLAIN REGULATIONS UPDATE DCA2018-00002
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Exhibit A
TTSD, TVF&R, and Pride Disposal were notified of the proposed code text amendment but
provided no comment.
City of Tualatin provided comments stating they have reviewed the proposal and have no
objections to it.
SECTION VI. PUBLIC COMMENTS
The City had not received any public comments at the time this report was written. At the Planning
Commission hearing on September 17, 2018, no member of the public attended; therefore, there
was no public testimony.
ATTACHMENTS:
Attachments:
1. Proposed Amendments:
a. 18.30 Definitions
b. 18.510 Sensitive Lands
^101 -- September 24,2018
PREPARED BY: tts4Lindor DA 1'h
Associate Planner
'00!" 'f September 24,2018
APPROVED BY: Tom McGuire DA 11,
Assistant Community Development Director
REQUIRED FEMA FLOODPLAIN REGULATIONS UPDA'T'E DCA2018-00002
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Exhibit A
Attachment 1a
Excerpt from 18.30,Definitions
18.30.020.A Definitions
70. Flood-related definitions:
a. "Base flood" - The flood having a one percent chance of being equaled or exceeded in any
given year.Also referred to as the"100-year flood."
b. "Critical facility"- A facility for which even a slight chance of flooding might be too great.
Critical facilities include,but are not limited to,schools;nursing homes;hospitals;police,fire,
and emergency response installations; and installations that produce, use, or store hazardous
materials or hazardous waste.
c. "Flood"-A general and temporary condition of partial or complete inundation of normally dr'
land areas from the overflow of inland or tidal waters or the unusual and rapid accumulation of
runoff of surface waters from any source.
d. "Floodway"-The channel of a river or other watercourse and the adjacent land areas that must
be reserved in order to discharge the base flood without cumulatively increasing the water
surface elevation more than one foot.
e. "Floodway fringe" -The area of the special flood hazard area lying outside of the floodway.
f. "Special Flood Hazard Area" - The land area covered by the floodwaters of the base flood is
the Special Flood Hazard Area (SFHA) on NFIP maps. The SFHA is the area where the
National Flood Insurance Program's (NFIP's) floodplain management regulations must be
enforced and the area where the mandatory purchase of flood insurance applies. The SFHA
includes Zones A, AO, AH, A1-30, AE, A99, AR, AR/A1-30, ARAE, AR/AO, AR/AH,
ARIA,VO,V 1-30,VE, and V.Also referred to as the"100-year floodplain."
Proposed Amendment
Exhibit A
Attachment 1b
Chapter 18.510
SENSITIVE LANDS
Sections:
18.510.010 Purpose
18.510.020 Applicability
18.510.030 Administrative Provisions
18.510.040 General Provisions for Special Flood Hazard Areas
18.510.050 General Provisions for Wetlands
18.510.060 Lapse of Approval and Extensions
18.510.070 Sensitive Lands Applications
18.510.080 Development within Locally Significant Wetlands and Along the Tualatin River,
Fanno Creek,Ball Creek,and the South Fork of Ash Creek
18.510.090 Adjustments to Base Zone Standards
18.510.100 Density Transfer and Reductions
18.510.110 Variances to Section 18.510.080 Standards
18.510.120 Plan Amendment Option
18.510.130 Significant Habitat Areas Map Verification Procedures
18.510.010 Purpose
A. Maintain integrity of rivers, streams,and creeks. Sensitive land regulations in this chapter are intended
to maintain the integrity of the rivers, streams, and creeks in Tigard by minimizing erosion,promoting
bank stability, maintaining and enhancing water quality and fish and wildlife habitats, and preserving
scenic quality and recreation potential.
B. Implement comprehensive plan and floodplain management program. The regulations of this chapter
are intended to implement the comprehensive plan and the city's floodplain management program as
required by the Federal Emergency Management Agency (FEMA) through the National Flood
Insurance Program, to help to preserve sensitive land areas from encroaching use,and to maintain the
November 1,2016October 19,2018,zero-foot rise floodway elevation.
C. Implement Clean Water Service (CWS) design and construction standards. The regulations of this
chapter are intended to protect the beneficial uses of water within the Tualatin River Basin in
compliance with the CWS"Design and Construction Standards."
D. Implement the Metro Urban Growth Management Functional Plan. The regulations of this chapter are
intended to protect the beneficial water uses and functions and values of resources within water quality
and flood management areas and to implement the performance standards of the Metro Urban Growth
Management Functional Plan.
E. Implement Statewide Planning Goal 5(Natural Resources).The regulations in this chapter are intended
to address the requirements of Statewide Planning Goal 5 (Natural Resources) and the safe harbor
provisions of the Goal 5 administrative rule pertaining to wetland and riparian corridors.
F. Protect public health, safety, and welfare. Sensitive land areas are designated as such to protect the
public health,safety,and welfare of the community through the regulation of these sensitive land areas.
G. Location. Sensitive lands are lands potentially unsuitable for development because of their location
within:
Sensitive Lands 18.510-1 Code Update:12/17Proposed Amendment
Exhibit A
Attachment 1 b
1. The special flood hazard area or 1996 flood inundation line,whichever is greater;
2. Natural drainageways;
3. Wetland areas that are regulated by the other agencies including the U.S.Army Corps of Engineers
and the Division of State Lands, or are designated as significant wetland on the City of Tigard
"Wetland and Stream Corridors Map";
4. Steep slopes of 25 percent or greater and unstable ground;and
5. Significant fish and wildlife habitat areas designated on the City of Tigard "Significant Habitat
Areas Map."(Ord. 17-22 §2)
18.510.020 Applicability
A. CWS stormwater connection permit. All proposed development shall obtain a stormwater connection
permit from CWS in compliance with its design and construction standards.
B. Outright permitted uses with no approval required. Except as provided below and by Subsections
18.510.020.D, F, and G of this section, the following uses are outright permitted uses within
drainageways,slopes that are 25 percent or greater,and unstable ground when the use does not involve
paving.For the purposes of this chapter,the word"structure"shall exclude:children's play equipment,
picnic tables,sand boxes,grills,basketball hoops,and similar recreational equipment.
1. Accessory uses such as lawns, gardens, or play areas; except in a water quality sensitive area or
vegetated corridor, as defined in the CWS "Design and Construction Standards" or the Statewide
Goal 5 vegetated corridor established for the Tualatin River,as defined in Section 18.510.080.
2. Farm uses conducted without locating a structure within the sensitive land area; except in a water
quality sensitive area or vegetative corridor, as defined in CWS "Design and Construction
Standards"or the Statewide Goal 5 vegetated corridor established for the Tualatin River,as defined
in Section 18.510.080.
3. Community recreation uses, excluding structures; except in a water quality sensitive area or
vegetated corridor, as defined in the CWS "Design and Construction Standards"or the Statewide
Goals vegetated corridor established for the Tualatin River, as defined in Section 18.510.080.
4. Public and private conservation areas for water, soil,open space,forest,and wildlife resources.
5. Removal of poison oak,tansy ragwort,blackberry,English ivy, or other noxious vegetation.
6. Maintenance of floodway excluding re-channeling; except in a water quality sensitive area or
vegetated corridor, as defined in the CWS "Design and Construction Standards"or the Statewide
Goal 5 vegetated corridor established for the Tualatin River, as defined in Section 18.510.080.
I 7. Fences;except in the floodway area;a water quality sensitive area or vegetated corridor,as defined
in the CSW "Design and Construction Standards"; or the Statewide Goal 5 vegetated corridor
established for the Tualatin River,as defined in Section 18.510.080.
Sensitive Lands 18.510-2 Code Update: 12/I7Proposed Amendment
Exhibit A
Attachment 1 b
8. Accessory structures that are less than 120 square feet in size;except in the-##deed a water
quality sensitive area or vegetated corridor, as defined in the CSW "Design and Construction
Standards";or the Statewide Goals vegetated corridor established for the Tualatin River,as defined
in Section 18.510.080.
9. Land form alterations involving up to 10 cubic yards of material; except in the floodway area; a
water quality sensitive area or vegetated corridor,as defined in the CSW"Design and Construction
Standards";or the Statewide Goal 5 vegetated corridor established for the Tualatin River,as defined
in Section 18.510.080.
C. Exemptions. When performed under the direction of the city, the following shall be exempt from the
provisions of this section:
1. Responses to public emergencies,including emergency repairs to public facilities;
2. Stream and wetlands restoration and enhancement programs, except in special flood hazard areas
when meeting the definition of development in paragraph 18.510.040.R.1;
3. Non-native vegetation removal;
4. Planting of native plant species; and
5. Routine maintenance or replacement of existing public facilities projects, except in special flood
hazard areas when meeting the definition of development in paragraph 18.510.040.R.1.
D. Jurisdictional wetlands. Landform alterations or developments that are only within wetland areas that
meet the jurisdictional requirements and permit criteria of the U.S.Army Corps of Engineers,Division
of State Lands,CWS, or other federal, state,or regional agencies,and are not designated as significant
wetlands on the City of Tigard"Wetland and Streams Corridors Map,"do not require a sensitive lands
review. The city shall require that all necessary approvals from other agencies are obtained. All other
applicable city requirements shall be met, including sensitive land reviews for areas within the special
flood hazard area, slopes of 25 percent or greater or unstable ground, drainageways, and wetlands that
are not under state or federal jurisdiction.
E. Administrative sensitive lands review.
1. Administrative sensitive lands reviews within the special flood hazard area (excluding the
floodwav), drainageway, slopes that are 25 percent or greater, and unstable ground shall be
processed through a Type I procedure,as provided in Section 18.710.050,for the following actions:
a. Tho installation of public support facilities shall be subject to compliance with all of tho
a. The repair,reconstruction, or improvement of an existing structure or utility,the cost of
which is less than 50 percent of the market value of the structure prior to the improvement or
the damage requiring reconstruction.
b. Actions within the special flood hazard area:
i. The construction of accessory structures up to 528 square feet in size;and
ii. Any land formations involving up to 50 cubic yards of material.
Sensitive Lands 18.510-3 Code Update:12/17Proposed Amendment
Exhibit A
Attachment l b
,, -•- - .
material, except in the floodway area., for land that is within public casements and rights of
way shall be subject to compliance with all of the standards in this chapter;
c. Actions within drainageways and slopes that are 25 percent or greater,and unstable ground:
e i. Minimal ground disturbances or landform alterations involving 10 to 50 cubic yards of
material, - . - -- '::: . . hall be subjcct to compliance with all of the
standards in this chapter; and
ii. Building permits for accessory structures that are 120 to 528 square feet in size.
d. The repair,reconstruction,or improvement of an existing structure or utility,the cost of which
is less than 50 percent of the market value of the structure prior to the improvement or the
damage requiring reconstruction provided no development occurs in the floodway shall be
subject to compliance with all of the standards in this chapter;
c. Building permits for accessory structures that arc 120 to 528 square feet in siza„ except in the
floodway area;
.- a - • .
of the standards in this chapter;
subject to compliance with all of the standards in this chapter;
with all of the standards in this chapter;
i. The construction of accessory structures that arc less than 120 square feet within special flood
j. Any land formations involving up to 10 cubic yards of material within special flood hazard
areas shall be subject to compliance with all of the standards in this chapter.
2. The approval authority shall approve, approve with conditions, or deny a sensitive land review
application using the standards and approval criteria Sections 18.510.040, 18.510.050, 18.510.070
and 18.510.080.
F. Sensitive lands approvals issued by the director.
1. Sensitive land reviews within drainageways, slopes that are 25 percent or greater or unstable
ground, and wetland areas that are not regulated by other local, state, or federal agencies and are
designated as significant wetlands on the City of Tigard "Wetland and Streams Corridors Map"
shall be processed through a Type II procedure,as provided in Section 18.710.060 for the following
actions:
a. Ground disturbance(s)or land form alterations involving more than 50 cubic yards of material;
Sensitive Lands 18.510-4 EB Proposed Amendment
Exhibit A
Attachment 1 b
b. Repair, reconstruction, or improvement of an existing structure or utility, the cost of which
equals or exceeds 50 percent of the market value of the structure prior to the improvement or
the damage requiring reconstruction;
c. Residential and nonresidential structures intended for human habitation; and
d. Accessory structures that are greater than 528 square feet in size, .
2. The approval authority shall approve, approve with conditions,or deny a sensitive lands review
application using the approval criteria provided in Section 18.510.070.
G. Sensitive lands approvals issued by the hearings officer.
1. Sensitive land reviews within special flood hazard areas shall by processed through a Type III-HO
procedure,as provided in Section 18.710.070,for the following actions:
a. Ground disturbance(s)or landform alterations in all floodway areas;
b. Ground disturbance(s)or landform alterations in floodway fringe locations involving more than
50 cubic yards of material;
c. Repair, reconstruction, or improvement of an existing structure or utility, the cost of which
equals or exceeds 50 percent of the market value of the structure prior to the improvement or
the damage requiring reconstruction provided no development occurs in the floodway;
d. Structures intended for human habitation;and
e. Accessory structures that are greater than 528 square feet in size,outside of floodway areas.
2. The approval authority shall approve,approve with conditions, or deny a sensitive lands review
application using the approval criteria provided in Section 18.510.070.
H. Other uses. Except as explicitly authorized by other provisions of this chapter, all other uses are
prohibited on sensitive land areas.
I. Nonconforming uses. A use established prior to the effective date of this title, which would be
prohibited by this chapter or that would be subject to the limitations and controls imposed by this
chapter, shall be considered a nonconforming use. Nonconforming uses shall be subject to the
provisions of Chapter 18.50,Nonconforming Circumstances. (Ord. 17-22 §2)
18.510.030 Administrative Provisions
A. Interagency coordination. The approval authority shall review all applications for a sensitive lands
review to determine that all necessary approvals shall be obtained from those federal, state, or local
governmental agencies,from which prior approval is also required.
As provided in CWS"Design and Construction Standards,"the necessary permits for all
"development"shall include a CWS service provider letter,which specifies the conditions and
requirements necessary, if any, for an applicant to comply with CWS water quality protection
standards and for the agency to issue a stormwater connection permit.
Sensitive Lands 18.510-5 Code Update:12/17Provosed Amendment
Exhibit A
Attachment 1b
B. Alteration or relocation of water course.
1. The director shall notify communities adjacent to the affected area and the State Department of
Land Conservation and Development prior to any alteration or relocation of a watercourse, and
submit evidence of such notification to the Federal Insurance Administration;
2. The director shall require that maintenance is provided within the altered or relocated portion of a
watercourse so that the flood-carrying capacity is not diminished.
C. Applicable standards and criteria.The approval authority shall apply the standards and criteria provided
in this chapter when reviewing an application for a sensitive lands review.
D. Elevation and floodproofing certification. The approval authority shall require that the elevations and
floodproofing certification required in Subsection 18.510.030.E be provided prior to permit issuance
and verification upon occupancy and final approval.
E. Maintenance of records.
1. Where base flood elevation data is provided through the flood insurance study,the building official
shall obtain and record the actual elevation (in relation to mean sea level) of the lowest floor
(including basement) of all new or substantially improved structures, and whether or not the
structure contains a basement;
2. For all new or substantially improved floodproofed structures,the building official shall:
a. Verify and record the actual elevation(in relation to mean sea level); and
b. Maintain the floodproofing certifications required in this chapter.
3. The director shall maintain for public inspection all other records pertaining to the provisions in
this chapter.(Ord. 17-22 §2)
18.510.040 General Provisions for Special Flood Hazard Areas
A. Review. The approval authority shall review all applications to determine whether proposed building
sites will minimize the potential for flood damage.
B. Special flood hazard. The areas of special flood hazard identified by FEMA in a scientific and
engineering report entitled "The Flood Insurance Study for Washington County, Oregon and
Incorporated Areas effective November'1,2016 October 19.2018"with accompanying Flood Insurance
Map is hereby adopted by reference and declared to be a part of this ordinance.
C. Base flood elevation data. When base flood elevation data has not been provided in compliance with
Subsection 18.510.040.B, the approval authority shall obtain, review and reasonably utilize any base
flood elevation and floodway data available from a federal, state or other source,in order to administer
Subsections 18.510.040.M and N.
D. Test of reasonableness. Where elevation data is not available either through the flood insurance study
or from another authoritative source,applications for building permits shall be reviewed to assure that
the potential for flood damage to the proposed construction will be minimized. The test of
reasonableness is a local judgment and includes use of historical data,high water marks,photographs
Sensitive Lands 18.510-6 Code Update: 12/17Proposed Amendment
Exhibit A
Attachment 1b
of past flooding, etc., where available. Failure to elevate at least 2 feet above grade in these sensitive
land areas may result in higher insurance rates.
E. Resistant to flood damage.All new construction and substantial improvements,including manufactured
homes,shall be constructed with materials and utility equipment resistant to flood damage.
F. Minimize flood damage. All new construction and substantial improvements, including manufactured
homes,shall be constructed using methods and practices that minimize flood damage.
G. Equipment protection. Electrical, heating, ventilation, plumbing, and air-conditioning equipment and
other service facilities shall be designed or otherwise elevated or located so as to prevent water from
entering or accumulating within the components during conditions of flooding.
H. Water supply systems. All new and replacement water supply systems shall be designed to minimize
or eliminate infiltration of floodwater into the system.
I. Anchoring. All new construction, all manufactured homes and substantial improvements shall be
anchored to prevent flotation,collapse, or lateral movement of the structure.
J. Sanitary sewerage systems. New and replacement sanitary sewerage systems shall be designed to
minimize or eliminate infiltration of floodwater into the systems and discharge from the systems into
floodwater.
K. On-site wastetef disposal systems. On-site wastetef disposal systems shall be located to avoid
impairment to them or contamination from them during flooding.
L. Residential construction.
1. New construction and substantial improvement of any residential structure,including manufactured
homes,shall have the lowest floor,including the basement,elevated at least 1 foot above base flood
elevation;
2. Fully enclosed areas below the lowest floor that are subject to flooding are prohibited,or shall be
designed to automatically equalize hydrostatic flood forces on exterior walls by allowing for the
entry and exit of floodwater. Designs for meeting this requirement shall either be certified by a
registered professional engineer or architect, or shall meet or exceed the following minimum
criteria:
a. A minimum of 2 openings having a total net area of not less than 1 square inch for every square
foot of enclosed area subject to flooding shall be provided;
b. The bottom of all openings shall be no higher than 1 foot above grade; and
c. Openings may be equipped with screens,louvers,or other coverings or devices,provided that
they permit the automatic entry and exit of flood waters.
3. Manufactured homes shall be securely anchored to an adequately anchored permanent foundation
system to prevent flotation, collapse, and lateral movement during the base flood. Anchoring
methods may include, but are not limited to, use of over-the-top or frame ties to ground anchors.
Electrical crossover connections shall be a minimum of 12 inches above base flood elevation.
Sensitive Lands 18.510-7 Code Update:12/17Proposed Amendment
Exhibit A
Attachment lb
M. Nonresidential construction. New construction and substantial improvement of any commercial,
industrial, or other nonresidential structure shall either have the lowest floor, including basement,
elevated to the level of the base flood elevation,or together with attendant utility and sanitary facilities,
shall:
1. Be floodproofed so that below the base flood level the structure is watertight with walls
substantially impermeable to the passage of water;
2. Have structural components capable of resisting hydrostatic and hydrodynamic loads and effects
of buoyancy;
3. Be certified by a registered professional engineer or architect that the design and methods of
construction are in compliance with accepted standards of practice for meeting provisions of this
subsection based on their development or review of the structural design,specifications and plans.
Such certifications shall be provided to the building official as provided in 18.510.030.E.2; and
4. Nonresidential structures that are elevated, not floodproofed, shall meet the same standards for
space below the lowest floor as described in Paragraph 18.510.040.L.2. Applicants flood-proofing
nonresidential buildings shall be notified that flood insurance premiums will be based on rates that
are 1 foot below the floodproofed level(e.g., a building constructed to the base flood level will be
rated as 1 foot below that level).
N. Subdivisions and partitions in special flood hazard areas. Subdivisions and partitions in the special
flood hazard area shall meet the following criteria:
1. The design shall minimize the potential for flood damage;
2. Public utilities and facilities such as sewer, gas, electrical, and water systems shall be located and
constructed so as to minimize flood damage;
3. Adequate drainage shall be provided to reduce exposure to flood damage; and
4. For subdivisions or partitions that contain more than 50 lots or 5 acres and where base flood
elevation data is not available from the Federal Emergency Management Agency (FEMA) or
another authoritative source,the applicant shall generate base flood elevation data to be reviewed
as part of the application.
0. Recreational vehicles.Recreational vehicles placed on sites within Zones Al-A30,AH, and AE on the
flood insurance rate map either:
1. Are on the site for fewer than 180 consecutive days;
2. Are fully licensed and ready for highway use:
a. Are on wheels or jacking system,
b. Are attached to the site only by quick disconnect type utilities and security devices, and have
no permanently attached additions,or
c. Meet the requirements of Subsections 18.510.040.E,F,1,and L and the elevation and anchoring
requirements for manufactured homes.
Sensitive Lands 18.510-8 Code Update:12/17Proposed Amendment
Exhibit A
Attachment 1 b
P. Critical facilities. Construction of new critical facilities shall be,to the extent possible,located outside
of the limits of the special flood hazard area.Construction of new critical facilities shall be permissible
within the special flood hazard area if no feasible alternative site is available. Critical facilities
constructed within the special flood hazard area shall have the lowest floor elevated 3 feet above base
flood elevation or to the height of the 500-year flood, whichever is higher. Access to and from the
critical facility should also be protected to the height utilized above. Floodproofing and sealing
measures shall be taken to ensure that toxic substances will not be displaced by or released into
floodwaters. Access routes elevated to or above the level of the base flood elevation shall be provided
to all critical facilities to the extent possible.
Q. Severability. If any section, clause, sentence, or phrase of the ordinance is held to be invalid or
unconstitutional by any court of competent jurisdiction, then said holding shall in no way affect the
validity of the remaining portions of this chapter.
R. Definitions. The following definitions are only applicable to this section:
1. Basement-Any area of the building having its floor subgrade(below ground level)on all sides.
2 ..l. DEVET OPMLNT Developmentmeans any man-made change to improved or unimproved
real estate, including but not limited to buildings or other structures, mining, dredging, filling,
grading,paving,excavation or drilling operations or storage of equipment or materials.
3. Elevated Building — For insurance purposed, a non-basement building and that has its lowest
elevated floor raised above ground level by foundation walls, shear walls, posts, piers, pilings, or
columns. A YlieVidtd a
pc# lb, 0114 ;)
4. 2. FLOOD INSURANCE RATE MAPFlood Insurance Rate Map(FIRM) The official Got.04
map of a community,on which the Federal Insurance Administrator has delineated both the special Y1 ec+d r�
hazard areas and the risk premium zones applicable to the community.A FIRM that has been made
available digitally is called a Digital Flood Insurance Rate Map(DFIRM).
5_3. FLOOD INSURANCE STUDYF1ood Insurance Study (FIS) means - tThe official report
provided by the Federal Insurance Administration that includes flood profiles,the Flood Boundary-
Floodway Map, and the water surface elevation of the base flood.
6_4. LOWEST EOGRLowest Floor - moans tThe lowest floor of the lowest enclosed area
(including basement). An unfinished or flood resistant enclosure, usable solely for parking of
vehicles, building access or storage in an area other than a basement area is not considered a
building's lowest floor; Provided, that such enclosure is not built so as to render the structure in
violation of the applicable non-elevation design requirements of Section 60.3.
7_5. MANUFACTURED HOMEManufactured Home-mems-aA structure,transportable in one or
more sections, which is built on a permanent chassis and is designed for use with or without a
permanent foundation when attached to the required utilities.The term"manufactured"home does
not include a"recreational vehicle."
8. Manufactured Home Park or Subdivision-A parcel(or contiguous parcels)of land divided into
two or more manufactured home lots for rent or sale.
91:, _ ! _ ' - e ew Construction - means =or the purposes of determining
insurance rates,structures for which the"start of construction"commenced on or after the effective
Sensitive Lands 18.510-9 Code Updte ' rProaosed Amendment
Exhibit A
Attachment lb
date of an initial FIRM or after December 31, 1974,whichever is later,and includes any subsequent
improvements to such structures. For floodplain management purposes, new construction means
structures for which the start of construction commenced on or after the effective date of a
floodplain management regulation adopted by a community and includes any subsequent
improvements to such structures.
10. 7. RECREATIONAL VEHICLERecreational Vehicle -means-aA vehicle which is: (a)Built on
a single chassis;(b)400 square feet or less when measured at the largest horizontal projection; (c)
Designed to be self-propelled or permanently towable by a light duty truck; and (d) Designed
primarily not for use as a permanent dwelling but as temporary living quarters for recreational,
camping,travel,or seasonal use.
11. 8. START OF CONSTRUCTIONStart of Construction--ilncludes substantial improvement,and
means the date the building permit was issued, provided the actual start of construction, repair,
reconstruction,placement or other improvement was within 180 days of the permit date.The actual
start means either the first placement of permanent construction of a structure on a site,such as the
pouring of slab or footings, the installation of piles, the construction of columns, or any work
beyond the stage of excavation; or the placement of a manufactured home on a foundation.
Permanent construction does not include land preparation,such as clearing,grading and filling;nor
does it include the installation of streets or walkways;nor does it include excavation for a basement,
footings,piers,or foundations or the erection of temporary forms;nor does it include the installation
on the property of accessory buildings, such as garages or sheds not occupied as dwelling units or
not part of the main structure.For a substantial improvement,the actual start of construction means
the first alteration of any wall, ceiling, floor, or other structural part of a building, whether or not
that alteration affects the external dimensions of the building.
12. 9:—StructureSTRUCTURE means,_€For floodplain management purposes, a walled and roofed
building, including a gas or liquid storage tank, that is principally above ground
13. 44—Substantial DamageUBSTANTIAL DAMAGE mean:,=dDamage of any origin sustained by a
structure whereby the cost of restoring the structure to its before-damaged condition would equal
or exceed 50 percent of the market value of the structure before the damage occurred.
14. Substantial Improvement-Any reconstruction,rehabilitation, addition, or other improvement of a
structure,the cost of which equals or exceeds 50 percent of the market value of the structure
either:
a. Before the"start of construction"of the improvement;or
b. If the structure has been damaged and is being restored,before the damage occurred.
c. The term does not,however, include either:
i. Any project for improvement of a structure to correct existing violations of state or
local health,sanitary,or safety code specifications which have been identified by the
local code enforcement official and which are the minimum necessary to assure safe
living conditions or
i-ii. Any alteration of a structure listed on the National Register of Historic Places or a State
Inventory of Historic Places,provided that the alteration will not preclude the
structure's designation as a`historic structure'.
15. -I-1—ViolationiOLATION means_ tThe failure of a structure or other development to be fully
compliant with the community's flood plain management regulations. A structure or other
development without the elevation certificate,other certifications,or other evidence of compliance
Sensitive Lands 18.510-10 Gede-Updatei-124Proposed Amendment
Exhibit A
Attachment 1 b
required in Section 60.3(b)(5), (c)(4), (c)(10), (d)(3), (e)(2), (e)(4), or(e)(5) is presumed to be in
violation until such time as that documentation is provided.
S. Disclaimer of liability.This section provides a reasonable degree of flood protection but does not imply
total flood protection.
T. Greater restriction. This section shall not in any way impair or remove the necessity of compliance
with any other applicable laws, ordinances, regulations, etc. Where this section imposes a greater
restriction,the provisions of this section shall control. (Ord. 17-22 §2)
U. New technical data. Notify FEMA within 6 months of project completion when an applicant has
obtained a Conditional Letter of Map Revision(CLOMR) from FEMA, or when development altered
a watercourse, modified floodplain boundaries, or modified Base Flood Elevations. This notification
shall beprovided as a Letter of Map Revision(LOMR).
18.510.050 General Provisions for Wetlands
A. Code compliance requirements. Wetland regulations apply to those areas classified as significant on
the City of Tigard"Wetland and Streams Corridors Map,"and to a vegetated corridor ranging from 25
to 200 feet wide, measured horizontally, from the defined boundaries of the wetland, as provided in
"Table 3.1, Vegetated Corridor Widths," and "Appendix C, Natural Resource Assessments," of the
CWS"Design and Construction Standards."Wetland locations may include but are not limited to those
areas identified as wetlands in "Wetland Inventory and Assessment for the City of Tigard, Oregon,"
Fishman Environmental Services, 1994.
B. Delineation of wetland boundaries. Precise boundaries may vary from those shown on wetland maps;
specific delineation of wetland boundaries may be necessary. Wetland delineation will be done by
qualified professionals at the applicant's expense. (Ord. 17-22 §2)
18.510.060 Lapse of Approval
A. Lapse of approval. Approval of a sensitive lands review shall lapse if:
1. Substantial construction of the approved plan has not begun within a 1.5 year period; or
2. Construction on the site is a departure from the approved plan.
B. Extensions.The director shall,upon written request by the applicant,grant an extension of the approval
period not to exceed 1 year,provided that:
1. No changes are made on the original plan as approved;
2. The applicant can show intent of initiating construction of the site within the 1-year extension
period;and
3. There have been no changes to the applicable comprehensive plan policies and ordinance
provisions on which the approval was based. (Ord. 17-22 §2)
18.510.070 Sensitive Lands Applications
A. Approval required. An applicant, who wishes to develop within a sensitive area, as defined in this
chapter, shall obtain approval in certain situations. Depending on the nature and intensity of the
Sensitive Lands 18.510-11 CodeProposed Amendment
Exhibit A
Attachment 1 b
proposed activity within a sensitive area, either a Type II or Type III review is required,as provided in
Subsections 18.510.020.F and G.The approval criteria for different types of sensitive areas are provided
in Subsections 18.510.070.B—E.
B. Within the special flood hazard area. The approval authority shall approve or approve with conditions
an application for sensitive lands review within the special flood hazard area when all of the following
criteria are met:
1. Compliance with all of the applicable requirements of this title;
2. Land form alterations shall preserve or enhance the special flood hazard area storage function and
maintenance of the zero-foot rise floodway shall not result in any encroachments, including fill,
new construction,substantial improvements and other development unless certified by a registered
professional engineer that the encroachment will not result in any increase in flood levels during
the base flood discharge;
a. If in the floodway and no-rise requirement is met, the development will comply with all
applicable flood hazard reduction provisions.
3. Land form alterations or developments within the special flood hazard area shall be allowed only
in areas designated as commercial or industrial on the comprehensive plan land use map, except
that alterations or developments associated with community service uses,utilities,or public support
facilities shall be allowed on residentially zoned properties subject to applicable zoning standards;
4. Where a land form alteration or development is permitted to occur within the special flood hazard
area it will not result in any increase in the water surface elevation of the 100-year flood;
5. The land form alteration or development plan includes a pedestrian/bicycle pathway in compliance
with the adopted pedestrian/bicycle pathway plan, unless the construction of said pathway is
deemed as untimely;
6. Pedestrian/bicycle pathway projects within the special flood hazard area shall include a wildlife
habitat assessment that shows the proposed alignment minimizes impacts to significant wildlife
habitat while balancing the community's recreation and environmental educational goals;
7. The necessary U.S. Army Corps of Engineers and State of Oregon Land Board,Division of State
Lands, and CWS permits and approvals shall be obtained;and
8. Where land form alterations or development are allowed within and adjacent to the special flood
hazard area,the city shall require the consideration of dedication of sufficient open land area within
and adjacent to the special flood hazard area in compliance with the comprehensive plan.This area
shall include portions of a suitable elevation for the construction of a pedestrian/bicycle pathway
within the special flood hazard area in compliance with the adopted pedestrian/bicycle pathway
plan.
C. With steep slopes. The approval authority shall approve or approve with conditions an application for
a sensitive lands review on slopes of 25 percent or greater or unstable ground when all of the following
criteria are met:
1. Compliance with all of the applicable requirements of this title;
Sensitive Lands 18.510-12 Code Updatc:12/17Proposed Amendment
Exhibit A
Attachment lb
2. The extent and nature of the proposed land form alteration or development will not create site
disturbances to an extent greater than that required for the use;
3. The proposed land form alteration or development will not result in erosion,stream sedimentation,
ground instability, or other adverse on-site and off-site effects or hazards to life or property;
4. The structures are appropriately sited and designed to ensure structural stability and proper drainage
of foundation and crawl space areas for development with any of the following soil conditions:
wet/high water table; high shrink-swell capability; compressible/organic; and shallow depth-to-
bedrock; and
5. Where natural vegetation has been removed due to land form alteration or development,the areas
not covered by structures or impervious surfaces will be replanted to prevent erosion in compliance
with Chapter 18.320,Landscaping and Screening.
D. Within drainageways. The approval authority shall approve or approve with conditions an application
for a sensitive lands review within drainageways when all of the following criteria are met:
1. Compliance with all of the applicable requirements of this title;
2. The extent and nature of the proposed land form alteration or development will not create site
disturbances to an extent greater than that required for the use;
3. The proposed land form alteration or development will not result in erosion,stream sedimentation,
ground instability,or other adverse on-site and off-site effects or hazards to life or property;
4. The water flow capacity of the drainageway is not decreased;
5. Where natural vegetation has been removed due to land form alteration or development, the areas
not covered by structures or impervious surfaces will be replanted to prevent erosion in compliance
with Chapter 18.320,Landscaping and Screening;
6. The drainageway will be replaced by a public facility of adequate size to accommodate maximum
flow in compliance with Clean Water Services requirements and the city's adopted stormwater
master plan;
7. The necessary U.S. Army Corps of Engineers and State of Oregon Land Board, Division of State
Lands,and CWS approvals shall be obtained;
8. Where land form alterations or development are allowed within and adjacent to the special flood
hazard area,the city shall require the consideration of dedication of sufficient open land area within
and adjacent to the special flood hazard area in compliance with the comprehensive plan.This area
shall include portions of a suitable elevation for the construction of a pedestrian/bicycle pathway
within the special flood hazard area in compliance with the adopted pedestrian bicycle pathway
plan.
E. Within wetlands.The approval authority shall approve or approve with conditions an application for a
sensitive lands review within wetlands when all of the following criteria are met:
1. Compliance with all of the applicable requirements of this title;
Sensitive Lands 18.510-13 Code Updatc: 11/J 7Proposed Amendment
Exhibit A
Attachment 1 b
2. The proposed land form alteration or development is neither on wetland in an area designated as
significant wetland on the comprehensive plan special flood hazard area and wetland map nor is
within the vegetative corridor as provided in "Table 3.1 Vegetative Corridor Widths" and
"Appendix C:Natural Resources Assessments"of the CWS"Design and Construction Standards,"
for such a wetland;
3. The extent and nature of the proposed land form alteration or development will not create site
disturbances to an extent greater than the minimum required for the use;
4. Any encroachment or change in on-site or off-site drainage that would adversely impact wetland
characteristics have been mitigated;
5. Where natural vegetation has been removed due to land form alteration or development, erosion
control provisions of the Surface Water Management program of Washington County shall be met
and areas not covered by structures or impervious surfaces will be replanted in like or similar
species in compliance with Chapter 18.320,Landscaping and Screening;
6. All other sensitive lands requirements of this chapter have been met;
7. The necessary U.S. Army Corps of Engineers and State of Oregon Land Board, Division of State
Lands,and CWS approvals shall be obtained;
8. The provisions of Chapter 18.520,Urban Forestry,shall be met;
9. Physical limitations and natural hazards, special flood hazard area and wetlands,natural areas,and
parks, recreation and open space policies of the comprehensive plan have been met. (Ord. 17-22
§2)
18.510.080 Special Provisions within Locally Significant Wetlands and Along the Tualatin
River,Fanno Creek,Ball Creek,and the South Fork of Ash Creek
A. In order to address the requirements of Statewide Planning Goal 5 (Natural Resources) and the safe
harbor provisions of the Goal 5 administrative rule (OAR 666-023-0030) pertaining to wetlands, all
wetlands classified as significant on the City of Tigard "Wetlands and Streams Corridors Map" are
protected.No land form alterations or developments are allowed within or partially within a significant
wetland, except as allowed/approved in compliance with Section 18.510.120.
B. In order to address the requirements of Statewide Planning Goal 5 (Natural Resources) and the safe
harbor provisions of the Goal 5 administrative rule (OAR 660-023-0030) pertaining to riparian
corridors, a standard setback distance or vegetated corridor area, measured horizontally from and
parallel to the top of the bank, is established for the Tualatin River,Fanno Creek,Ball Creek, and the
South Fork of Ash Creek.
1. The standard width for "good condition" vegetated corridors along the Tualatin River is 75 feet,
unless wider in compliance with CWS "Design and Construction Standards," or modified in
compliance with Section 18.510.120. If all or part of a locally significant wetland (a wetland
identified as significant on the City of Tigard "Wetlands and Streams Corridors Map") is located
within the 75-foot setback area, the vegetated corridor is measured from the upland edge of the
associated wetland.
Sensitive Lands 18.510-14 Code Update: 12/I7Proposed Amendment
Exhibit A
Attachment 1 b
2. The standard width for"good condition"vegetated corridors along Fanno Creek, Ball Creek, and
the South Fork of Ash Creek is 50 feet, unless wider in compliance with CWS "Design and
Construction Standards," or modified in compliance with Section 18.510.120. If all or part of a
locally significant wetland(a wetland identified as significant on the City of Tigard"Wetlands and
Streams Corridors Map") is located within the 50-foot setback area, the vegetated corridor is
measured from the upland edge of the associated wetland.
3. The minimum width for"marginal or degraded condition"vegetated corridors along the Tualatin
River, Fanno Creek, Ball Creek, and the South Fork of Ash Creek is 50 percent of the standard
width,unless wider in compliance with CWS"Design and Construction Standards,"or modified in
compliance with Section 18.510.120.
4. The determination of corridor condition shall be based on the natural resource assessment
guidelines as provided in the CWS "Design and Construction Standards."
5. The standard setback distance or vegetated corridor area applies to all development proposed on
property located within or partially within the vegetated corridors,except as allowed below:
a. Roads, pedestrian or bike paths crossing the vegetated corridor from one side to the other in
order to provide access to the sensitive area or across the sensitive area,as approved by the city
in compliance with Section 18.510.070 and by CWS "Design and Construction Standards";
b. Utility/service provider infrastructure construction (i.e. storm, sanitary sewer, water, phone,
gas,cable, etc.), if approved by the city and CWS;
c. A pedestrian or bike path, not exceeding 10 feet in width and in compliance with the CWS
"Design and Construction Standards";
d. Grading for the purpose of enhancing the vegetated corridor,as approved by the city and CWS;
e. Measures to remove or abate hazards,nuisances,or fire and life safety violations, as approved
by the regulating jurisdiction;
f. Enhancement of the vegetated corridor for water quality or quantity benefits, fish, or wildlife
habitat, as approved by the city and CWS;
g. Measures to repair, maintain, alter, remove, add to, or replace existing structures, roadways,
driveways, utilities, accessory uses, or other developments provided they are in compliance
with city and CWS regulations, and do not encroach further into the vegetated corridor or
sensitive area than allowed by the CWS"Design and Construction Standards."
6. Land form alterations or developments located within or partially within the Goal 5 safeharbor
setback or vegetated corridor areas established for the Tualatin River, Fanno Creek, Ball Creek,
and the South Fork of Ash Creek that meet the jurisdictional requirements and permit criteria of
the CWS, U.S. Army Corps of Engineers, Department of State Lands, or other federal, state, or
regional agencies,are not subject to this subsection B,except where the:
a. Land form alterations or developments are located within or partially within a good condition
vegetated corridor,as provided in Paragraphs 18.510.080.B.I and 2;
Sensitive Lands 18.510-15 Proposed Amendment
Exhibit A
Attachment lb
b. Land form alterations or developments are located within or partially within the minimum
width area established for marginal or a degraded condition vegetated corridor, as provided in
Paragraph 18.510.080.8.3.
These exceptions reflect instances of the greater protection of riparian corridors provided by the
safe harbor provisions of the Goal 5 administrative rule. (Ord. 17-22 §2)
18.510.090 Adjustments to Base Zone Standards
A. Adjustment. The approval authority may approve up to 50 percent adjustment to any dimensional
standard(e.g., setback, height or lot area) of the base zone to allow development when necessary to
further the purpose of this chapter.The purpose of the adjustment process is to reduce adverse impacts
on wetlands, stream corridors, fish and wildlife habitat, water quality and the potential for slope of
flood hazards. The approval authority may impose any reasonable condition necessary to mitigate
identified impacts resulting from development on otherwise unbuildable land.
B. Adjustment criteria. A special adjustment to the standards in the applicable base zone is processed
through a Type II procedure,as provided in Section 18.710.060,when development is proposed within
or adjacent to the vegetated corridor area or within or adjacent to areas designated as"strictly limit"or
"moderately limit" on the City of Tigard"Significant Habitat Areas Map." Verification of significant
habitat boundaries shall be done in compliance with the procedures provided in Section 18.510.130.
The approval authority shall approve or approve with conditions adjustments when all the following
are met:
1. The adjustment is the minimum necessary to allow a permitted use, while at the same time
minimizing disturbance to a water resource,riparian setback area or water quality buffer;
2. Explicit consideration has been given to maximizing vegetative cover,minimizing excavation and
minimizing impervious surface area on buildable land;
3. Design options have been considered to reduce the impacts of development, including, but not
limited to, multi-story construction, siting of the residence close to the street to reduce driveway
distance, maximizing the use of native landscaping materials, minimizing parking areas,
minimizing hydrologic impacts and garage space;
4. In no case shall the impervious surface area as a single-family residence (including the building
footprint, driveway and parking areas, accessory structures, swimming pools and patios) exceed
3,000 square feet of a vegetated corridor area;
5. Assurances are in place to guarantee that future development will not encroach further on land
under the same ownership within the vegetated corridor area;
6. Protected vegetated corridor,significant habitat areas and adjacent buffer areas shall be:
a. Placed in a non-buildable tract or protected with a restrictive easement;
b. Restoration and enhancement of habitat and buffer areas required, including monitoring for 5
years. (Ord. 17-22 §2)
18.510.100 Density Transfer and Reductions
Sensitive Lands 18.510-16 Codc Updatc: 12/17Proposed Amendment
Exhibit A
Attachment 1 b
A. Density transfer. Density may be transferred from vegetated corridor areas as provided in Sections
18.40.020 and 18.110.040.
B. Density reduction. The minimum number of units required by Chapter 18.110,Residential Zones,
may be waived if necessary to ensure that impacts on habitat areas are minimized. The amount of
reduction in the minimum density shall be calculated by subtracting the number of square feet of
inventoried significant habitat that is permanently protected from the total number of square feet used
to calculate the minimum density requirement. The approval authority may impose any reasonable
condition necessary to mitigate identified impacts resulting from development on otherwise
unbuildable land.
The adjustment shall be processed through a Type II procedure. The approval authority shall approve,
approve with conditions or deny the adjustment provided that the proposal will directly result in the
protection of significant habitat areas through placement in a non-buildable tract or protected with a
restrictive easement. (Ord. 17-22 §2)
18.510.110 Variances to Section 18.510.080 Standards
A. Approval process. Applications for variances from dimensional provisions of this chapter shall be
processed through a Type II procedure,as provided in Section 18.710.060,using the criteria in Chapter
18.790,Variances and Adjustments.
B. Additional criteria. In addition to the variance criteria in Chapter 18.790, Variances and Adjustments,
all the following additional criteria shall be met to grant a variance to any dimensional standard of this
chapter:
1. The variance is necessary to allow reasonable economic use of the subject property,which is owned
by the applicant,and was not created after the effective date of this chapter;
2. Strict application of the provisions of this chapter would otherwise result in the loss of a buildable
site for a use that is permitted outright in the base zone, and for which the applicant has submitted
a formal application;
3. The applicant has exhausted all options available under this chapter to relieve the hardship;
4. Based on review of all required studies identical to those described in Section 3.02.5.c Tier 2
Alternatives Analysis of the CWS "Design and Construction Standards," the variance is the
minimum necessary to afford relief, considering the potential for increased flood and erosion
hazard, and potential adverse impacts on native vegetation, fish and wildlife habitat, and water
quality;
5. Based on review of all required studies identical to those described in Section 3.02.5 of the CWS
"Design and Construction Standards,"no significant adverse impacts on water quality, erosion or
slope stability will result from approval of this hardship variance, or these impacts have been
mitigated to the greatest extent possible;
6. Loss of vegetative cover shall be minimized. Any lost vegetative cover shall be replaced on-site,
on a square foot for square foot basis, by native vegetation. (Ord. 17-22 §2)
18.510.120 Plan Amendment Option
Sensitive Lands 18.510-17 Code Update: 12/17Proposed Amendment
Exhibit A
Attachment lb
A. Comprehensive plan amendment.Any owner of property affected by the Goal 5 safeharbor(1)
protection of significant wetlands or(2)vegetated areas established for the Tualatin River,Fanno
Creek,Ball Creek,and the South Fork of Ash Creek may apply for a comprehensive plan amendment
as provided in Chapter 18.795,Map and Text Amendments. This amendment shall be based on a
specific development proposal. The effect of the amendment would be to remove Goal 5 protection
from the property,but not to remove the requirements related to the CWS Stormwater Connection
Permit,which shall be addressed separately through an alternatives analysis,as described in Section
3.02.5 of the CWS "Design and Construction Standards."The applicant shall demonstrate that such
an amendment is justified by either of the following:
B. ESEE analysis. The applicant may prepare an environmental, social, economic and energy (ESEE)
consequences analysis prepared in compliance with OAR 660-23-040.
1. The analysis shall consider the ESEE consequences of allowing the proposed conflicting use,
considering both the impacts on the specific resource site and the comparison with other
comparable sites within the Tigard Planning Area;
2. The ESEE analysis shall demonstrate to the satisfaction of the city council that the adverse
economic consequences of not allowing the conflicting use are sufficient to justify the loss, or
partial loss,of the resource;
3. In particular, ESEE analysis shall demonstrate why the use cannot be located on buildable land,
consistent with the provisions of this chapter, and that there are no other sites within the Tigard
Planning Area that can meet the specific needs of the proposed use;
4. The ESEE analysis shall be prepared by a team consisting of a wildlife biologist or wetlands
ecologist and a land use planner or land use attorney, all of whom are qualified in their respective
fields and experienced in the preparation of Goal 5 ESEE analysis;
5. If the application is approved,then the ESEE analysis shall be incorporated by reference into the
Tigard Comprehensive Plan,and the"Tigard Wetland and Stream Corridor Map"shall be amended
to remove the site from the inventory.
C. Demonstration of change. In this case,the applicant shall demonstrate that the sensitive area site(s)no
longer meet(s)the applicable significance threshold defined by the Goal 5 administrative rule,relative
to other comparable resources within the Tigard Planning Area.
1. Significance thresholds are described and applied in the addendum to the City of Tigard Local
Wetlands Inventory adopted by reference as part of this chapter.
2. In considering this claim, the city council shall determine that the decline in identified resource
values did not result from a violation of this title. (Ord. 17-22 §2)
18.510.130 Significant Habitat Areas Map Verification Procedures
A. Applicants who concur that the significant habitat areas map is accurate shall submit the following
information to serve as the basis for verifying the boundaries of inventoried habitat areas:
1. Submission requirements.
a. A detailed property description;
Sensitive Lands 18.510-18 Code Update: 12/17Proposed Amendment
Exhibit A
Attachment 1 b
b. A scale map of the property showing the locations of significant habitat areas, any existing
built area,wetlands or water bodies,Clean Water Services'vegetated corridor,the special flood
hazard area,the 1996 flood inundation line, and contour lines (2-foot intervals for slope less
than 15 percent and 10-foot intervals for slopes 15 percent or greater); and
c. A current aerial photograph of the property.
2. The approval authority's decision shall be based on consideration of submitted information, site
visit information, and other factual information. Should the applicant disagree with the
determination on the location of significant habitat areas on the property, the precise boundaries
shall be verified by the applicant in compliance with the detailed delineation methodology outlined
in Subsection 18.510.130.B.
B. Applicants who believe that the map is inaccurate shall submit a detailed delineation conducted by a
qualified professional in compliance with the following methodology to verify the precise boundaries
of the inventoried habitat areas by means of a Type II procedure.
1. Verifying boundaries of inventoried riparian habitat. Locating habitat and determining its riparian
habitat class is a 4-step process:
a. Locate the water feature that is the basis for identifying riparian habitat.
i. Locate the top of bank of all streams,rivers,and open water within 200 feet of the property.
ii. Locate the special flood hazard area or 1996 flood inundation line, whichever is greater,
within 100 feet of the property.
iii. Locate all wetlands within 150 feet of the property. Identified wetlands on the property
shall be further delineated consistent with methods currently accepted by the Oregon
Division of State Lands and the U.S.Army Corps of Engineers.
b. Identify the vegetative cover status of all areas on the property that are within 200 feet of the
top of bank of streams,rivers,and open water,are wetlands or are within 150 feet of wetlands,
and are flood areas and within 100 feet of flood areas.
i. Vegetative cover status shall be as identified on the metro vegetative cover map.
ii. The vegetative cover status of a property may be adjusted only if(a) the property was
developed prior to the time the regional program was approved; or(b)an error was made
at the time the vegetative cover status was determined. To assert the latter type of error,
applicants shall submit an analysis of the vegetative cover on their property using summer
2002 aerial photographs and the following definition of vegetative cover types in Table
18.510.1.
Table 18310.1
Definitions of Vegetative Cover Types
Definition
Low structure vegetation Areas that are part of a contiguous area 1 acre or larger of grass,meadow,
or open soils croplands,or areas of open soils located within 300 feet of a surface
stream low structure vetetation areas ma include areas of shrub
Sensitive Lands 18.510-19 Code Update: 12/17Proposed Amendment
Exhibit A
Attachment lb
vegetation less than 1 acre in size if they are contiguous with areas of
grass,meadow, croplands,orchards,Christmas tree farms,holly farms,or
areas of open soils located within 300 feet of a surface stream and
together form an area of 1 acre in size or larger).
Woody vegetation Areas that are part of a contiguous area 1 acre or larger of shrub or open
or scattered forest canopy(less than 60 percent crown closure)located
within 300 feet of a surface stream.
Forest canopy Areas that are part of a contiguous grove of trees 1 acre or larger in area
with approximately 60 percent or greater crown closure,irrespective of
whether the entire grove is within 200 feet of the relevant water feature.
c. Determine whether the degree that the land slope upward from all streams, rivers, and open
water within 200 feet of the property is greater than or less than 25 percent(using the vegetated
corridor measurement methodology as provided in Clean Water Services Design and
Construction Standards;and
d. Identify the riparian habitat classes applicable to all areas on the property using Table 18.510.2
and Table 18.510.3.
Sensitive Lands 18.510-20 Code Update: 12/17Proposed Amendment
Exhibit A
Attachment 1b
Table 18.510.2
Method for Locating Boundaries of Class 1 and H Riparian Areas
Distance Development/Vegetation Status[1]
in feet
from Developed areas Woody vegetation
water not providing Low structure vegetation (shrub and scattered Forest canopy(closed
feature vegetative cover or open soils forest canopy) to open forest canopy)
Surface streams
0-50 Class II Class I Class I Class I
50-100 Class II [2] Class I Class I
100-150 Class II[2]if slope>25 Class II[2]if slope> Class II [2]
percent 25 percent
150-200 Class II [2]if slope>25 Class II [2]if slope> Class II [2]if slope>
percent 25 percent 25 percent
Wetlands(Wetland feature itself is a Class I Riparian Area)
0-100 Class II [2] Class I Class I
100-150 Class II [2]
Flood Areas(Undeveloped portion of flood area is a Class I Riparian Area)
0-100 I 'Class II [2] 'Class II [2]
[1] The vegetative cover type assigned to any particular area was based on 2 factors:the type of
vegetation observed in aerial photographs and the size of the overall contiguous area of vegetative
cover to which a particular piece of vegetation belonged.As an example of how the categories were
assigned, in order to qualify as a"forest canopy"the forested area had to be part of a larger patch of
forest land at least 1 acre in size.
[2] Areas that have been identified as habitats of concern,as designated on the Metro Habitats of
Concern Map, shall be treated as Class I riparian habitat areas in all cases,subject to the provision of
additional information that establishes that they do not meet the criteria used to identity habitats of
concern as described in Metro's Technical Report for Fish and Wildlife.Examples of habitats of
concern include: Oregon white oak woodlands,bottomland hardwood forests,wetlands,native
grasslands,riverine islands or deltas,and important wildlife migration corridors.
Table 18.510.3
Tualatin Basin "Limit" Decision 111
Conflicting Use Category
Resource Future Urban
Category High Intensity (2002 and 2004 Non-Urban
Urban Other Urban additions) (outside UGB)
Class I&II Riparian Inside Moderately Limit Strictly Limit Strictly Limit N/A
Vegetated Corridor
Class I&II Riparian Moderately Limit Moderately Limit Moderately Limit Moderately Limit
Outside Vegetated Corridor
All other Resource Areas Lightly Limit Lightly Limit Lightly Limit Lightly Limit
Inner Impact Area Lightly Limit Lightly Limit Lightly Limit Lightly Limit
Outer Impact Area Lightly Limit Lightly Limit Lightly Limit Lightly Limit
Sensitive Lands 18.510-21 Code Update:12/1 Proposed Amendment
Exhibit A
Attachment lb
[1] Vegetated corridor standards are applied consistently throughout the District; in HIU areas they
supersede the"limit"decision.
2. Verifying boundaries of inventoried upland habitat was identified based on the existence of
contiguous patches of forest canopy, with limited canopy openings. The "forest canopy"
designation is made based on analysis of aerial photographs as part of determining the vegetative
cover status of land within the region. Upland habitat shall be as identified on the Significant
Habitat Areas Map unless corrected as provided in this subsection.
a. The only allowed corrections to the vegetative cover status of a property area as follows:
i. To correct errors made when the vegetative status of an area was determined based on
analysis of the aerial photographs used to inventory the habitat. The perimeter of an area
delineated as"forest canopy"on the Metro Vegetative Cover Map may be adjusted to more
precisely indicate the dripline of the trees within the canopied area provided that no areas
providing greater than 60 percent canopy crown closure are de-classified from the"forest
canopy" designation. To assert such errors, applicants shall submit an analysis of the
vegetative habitat cover on their property using the aerial photographs that were used to
inventory the habitat and the definitions of the different vegetative cover types provided in
Table 18.510.1; and
ii. To remove tree orchards and Christmas tree farms from inventoried habitat; provided,
however, that Christmas tree farms where the trees were planted prior to 1975 and have
not been harvested for sale as Christmas trees shall not be removed from the habitat
inventory.
b. If the vegetative cover status of any area identified as upland habitat is corrected in compliance
with Subparagraph 18.510.130.B.2.a to change the status of an area originally identified as
"forest canopy,"then such area shall not be considered upland habitat unless it remains part of
a forest canopy opening less than 1 acre in area completely surrounded by an area of contiguous
forest canopy. (Ord. 17-22 §2) ■
Sensitive Lands 18.510-22 Code Update: 12/17Proposed Amendment
Exhibit B
Excerpt from 18.30,Definitions
18.30.020.A Definitions
70. Flood-related definitions:
a. "Base flood" - The flood having a one percent chance of being equaled or exceeded in any
given year.Also referred to as the"100-year flood."
b. "Critical facility"- A facility for which even a slight chance of flooding might be too great.
Critical facilities include,but are not limited to,schools;nursing homes;hospitals;police,fire,
and emergency response installations; and installations that produce, use, or store hazardous
materials or hazardous waste.
c. "Flood"-A general and temporary condition of partial or complete inundation of normally dry
land areas from the overflow of inland or tidal waters or the unusual and rapid accumulation of
runoff of surface waters from any source.
d. "Floodway"-The channel of a river or other watercourse and the adjacent land areas that must
be reserved in order to discharge the base flood without cumulatively increasing the water
surface elevation more than one foot.
e. "Floodway fringe"-The area of the special flood hazard area lying outside of the floodway.
f. "Special Flood Hazard Area" - The land area covered by the floodwaters of the base flood is
the Special Flood Hazard Area (SFHA) on NFIP maps. The SFHA is the area where the
National Flood Insurance Program's (NFIP's) floodplain management regulations must be
enforced and the area where the mandatory purchase of flood insurance applies. The SFHA
includes Zones A, AO, AH, Al-30, AE, A99, AR, AR/A1-30, ARAE, AR/A0, AR/AH,
ARIA,VO,V1-30, VE,and V.Also referred to as the"100-year floodplain."
Proposed Amendment
Exhibit C
Chapter 18.510
SENSITIVE LANDS
Sections:
18.510.010 Purpose
18.510.020 Applicability
18.510.030 Administrative Provisions
18.510.040 General Provisions for Special Flood Hazard Areas
18.510.050 General Provisions for Wetlands
18.510.060 Lapse of Approval and Extensions
18.510.070 Sensitive Lands Applications
18.510.080 Development within Locally Significant Wetlands and Along the Tualatin River,
Fanno Creek,Ball Creek,and the South Fork of Ash Creek
18.510.090 Adjustments to Base Zone Standards
18.510.100 Density Transfer and Reductions •
18.510.110 Variances to Section 18.510.080 Standards
18.510.120 Plan Amendment Option
18.510.130 Significant Habitat Areas Map Verification Procedures
18.510.010 Purpose
A. Maintain integrity of rivers,streams,and creeks. Sensitive land regulations in this chapter are intended
to maintain the integrity of the rivers, streams,and creeks in Tigard by minimizing erosion,promoting
bank stability, maintaining and enhancing water quality and fish and wildlife habitats, and preserving
scenic quality and recreation potential.
B. Implement comprehensive plan and floodplain management program. The regulations of this chapter
are intended to implement the comprehensive plan and the city's floodplain management program as
required by the Federal Emergency Management Agency (FEMA) through the National Flood
Insurance Program,to help to preserve sensitive land areas from encroaching use,and to maintain the
October 19,2018,zero-foot rise floodway elevation.
C. Implement Clean Water Service (CWS) design and construction standards. The regulations of this
chapter are intended to protect the beneficial uses of water within the Tualatin River Basin in
compliance with the CWS"Design and Construction Standards."
D. Implement the Metro Urban Growth Management Functional Plan.The regulations of this chapter are
intended to protect the beneficial water uses and functions and values of resources within water quality
and flood management areas and to implement the performance standards of the Metro Urban Growth
Management Functional Plan.
E. Implement Statewide Planning Goal 5(Natural Resources).The regulations in this chapter are intended
to address the requirements of Statewide Planning Goal 5 (Natural Resources) and the safe harbor
provisions of the Goal 5 administrative rule pertaining to wetland and riparian corridors.
F. Protect public health, safety, and welfare. Sensitive land areas are designated as such to protect the
public health,safety,and welfare of the community through the regulation of these sensitive land areas.
G. Location. Sensitive lands are lands potentially unsuitable for development because of their location
within:
Sensitive Lands 18.510-1 Proposed Amendment
Exhibit C
1. The special flood hazard area or 1996 flood inundation line, whichever is greater;
2. Natural drainageways;
3. Wetland areas that are regulated by the other agencies including the U.S.Army Corps of Engineers
and the Division of State Lands, or are designated as significant wetland on the City of Tigard
"Wetland and Stream Corridors Map";
4. Steep slopes of 25 percent or greater and unstable ground; and
5. Significant fish and wildlife habitat areas designated on the City of Tigard "Significant Habitat
Areas Map."(Ord. 17-22 §2)
18.510.020 Applicability
A. CWS stormwater connection permit. All proposed development shall obtain a stormwater connection
permit from CWS in compliance with its design and construction standards.
B. Outright permitted uses with no approval required. Except as provided below and by Subsections
18.510.020.D, F, and G of this section, the following uses are outright permitted uses within
drainageways,slopes that are 25 percent or greater,and unstable ground when the use does not involve
paving.For the purposes of this chapter,the word"structure"shall exclude:children's play equipment,
picnic tables,sand boxes,grills,basketball hoops, and similar recreational equipment.
1. Accessory uses such as lawns, gardens, or play areas; except in a water quality sensitive area or
vegetated corridor, as defined in the CWS "Design and Construction Standards"or the Statewide
Goal 5 vegetated corridor established for the Tualatin River,as defined in Section 18.510.080.
2. Farm uses conducted without locating a structure within the sensitive land area; except in a water
quality sensitive area or vegetative corridor, as defined in CWS "Design and Construction
Standards"or the Statewide Goals vegetated corridor established for the Tualatin River,as defined
in Section 18.510.080.
3. Community recreation uses, excluding structures; except in a water quality sensitive area or
vegetated corridor, as defined in the CWS "Design and Construction Standards"or the Statewide
Goal 5 vegetated corridor established for the Tualatin River,as defined in Section 18.510.080.
4. Public and private conservation areas for water, soil,open space,forest,and wildlife resources.
5. Removal of poison oak,tansy ragwort,blackberry,English ivy,or other noxious vegetation.
6. Maintenance of floodway excluding re-channeling; except in a water quality sensitive area or
vegetated corridor, as defined in the CWS "Design and Construction Standards"or the Statewide
Goal 5 vegetated corridor established for the Tualatin River,as defined in Section 18.510.080.
7. Fences; except in a water quality sensitive area or vegetated corridor, as defined in the CSW
"Design and Construction Standards"; or the Statewide Goal 5 vegetated corridor established for
the Tualatin River,as defined in Section 18.510.080.
Sensitive Lands 18.510-2 Proposed Amendment
Exhibit C
8. Accessory structures that are less than 120 square feet in size; except in a water quality sensitive
area or vegetated corridor, as defined in the CSW "Design and Construction Standards"; or the
Statewide Goal 5 vegetated corridor established for the Tualatin River, as defined in Section
18.510.080.
9. Land form alterations involving up to 10 cubic yards of material;except in a water quality sensitive
area or vegetated corridor, as defined in the CSW "Design and Construction Standards"; or the
Statewide Goal 5 vegetated corridor established for the Tualatin River, as defined in Section
18.510.080.
C. Exemptions. When performed under the direction of the city,the following shall be exempt from the
provisions of this section:
1. Responses to public emergencies,including emergency repairs to public facilities;
2. Stream and wetlands restoration and enhancement programs, except in special flood hazard areas
when meeting the definition of development in paragraph 18.510.040.R.1;
3. Non-native vegetation removal;
4. Planting of native plant species; and
5. Routine maintenance or replacement of existing public facilities projects, except in special flood
hazard areas when meeting the definition of development in paragraph 18.510.040.R.1.
D. Jurisdictional wetlands. Landform alterations or developments that are only within wetland areas that
meet the jurisdictional requirements and permit criteria of the U.S.Army Corps of Engineers,Division
of State Lands,CWS,or other federal,state,or regional agencies,and are not designated as significant
wetlands on the City of Tigard"Wetland and Streams Corridors Map,"do not require a sensitive lands
review. The city shall require that all necessary approvals from other agencies are obtained. All other
applicable city requirements shall be met, including sensitive land reviews for areas within the special
flood hazard area, slopes of 25 percent or greater or unstable ground, drainageways, and wetlands that
are not under state or federal jurisdiction.
E. Administrative sensitive lands review.
1. Administrative sensitive lands reviews within the special flood hazard area (excluding the
floodway), drainageway, slopes that are 25 percent or greater, and unstable ground shall be
processed through a Type I procedure,as provided in Section 18.710.050,for the following actions:
a. The repair,reconstruction,or improvement of an existing structure or utility,the cost of
which is less than 50 percent of the market value of the structure prior to the improvement or
the damage requiring reconstruction.
b. Actions within the special flood hazard area:
i. The construction of accessory structures up to 528 square feet in size;and
ii. Any land formations involving up to 50 cubic yards of material.
Sensitive Lands 18.510-3 Proposed Amendment
Exhibit C
c. Actions within drainageways and slopes that are 25 percent or greater,and unstable ground:
i. Minimal ground disturbances or landform alterations involving 10 to 50 cubic yards of
material;and
ii. Building permits for accessory structures that are 120 to 528 square feet in size.
2. The approval authority shall approve, approve with conditions, or deny a sensitive land review
application using the standards and approval criteria Sections 18.510.040, 18.510.050, 18.510.070
and 18.510.080.
F. Sensitive lands approvals issued by the director.
1. Sensitive land reviews within drainageways, slopes that are 25 percent or greater or unstable
ground, and wetland areas that are not regulated by other local, state, or federal agencies and are
designated as significant wetlands on the City of Tigard "Wetland and Streams Corridors Map"
shall be processed through a Type II procedure,as provided in Section 18.710.060 for the following
actions:
a. Ground disturbance(s)or land form alterations involving more than 50 cubic yards of material;
b. Repair, reconstruction, or improvement of an existing structure or utility, the cost of which
equals or exceeds 50 percent of the market value of the structure prior to the improvement or
the damage requiring reconstruction;
c. Residential and nonresidential structures intended for human habitation; and
d. Accessory structures that are greater than 528 square feet in size.
2. The approval authority shall approve, approve with conditions,or deny a sensitive lands review
application using the approval criteria provided in Section 18.510.070.
G. Sensitive lands approvals issued by the hearings officer.
1. Sensitive land reviews within special flood hazard areas shall by processed through a Type III-HO
procedure,as provided in Section 18.710.070,for the following actions:
a. Ground disturbance(s)or landform alterations in all floodway areas;
b. Ground disturbance(s)or landform alterations in floodway fringe locations involving more than
50 cubic yards of material;
c. Repair, reconstruction, or improvement of an existing structure or utility, the cost of which
equals or exceeds 50 percent of the market value of the structure prior to the improvement or
the damage requiring reconstruction provided no development occurs in the floodway;
d. Structures intended for human habitation;and
e. Accessory structures that are greater than 528 square feet in size, outside of floodway areas.
Sensitive Lands 18.510-4 Proposed Amendment
Exhibit C
2. The approval authority shall approve, approve with conditions, or deny a sensitive lands review
application using the approval criteria provided in Section 18.510.070.
H. Other uses. Except as explicitly authorized by other provisions of this chapter, all other uses are
prohibited on sensitive land areas.
I. Nonconforming uses. A use established prior to the effective date of this title, which would be
prohibited by this chapter or that would be subject to the limitations and controls imposed by this
chapter, shall be considered a nonconforming use. Nonconforming uses shall be subject to the
provisions of Chapter 18.50,Nonconforming Circumstances. (Ord. 17-22 §2)
18.510.030 Administrative Provisions
A. Interagency coordination. The approval authority shall review all applications for a sensitive lands
review to determine that all necessary approvals shall be obtained from those federal, state, or local
governmental agencies, from which prior approval is also required.
As provided in CWS "Design and Construction Standards,"the necessary permits for all
"development"shall include a CWS service provider letter,which specifies the conditions and
requirements necessary,if any,for an applicant to comply with CWS water quality protection
standards and for the agency to issue a stormwater connection permit.
B. Alteration or relocation of water course.
1. The director shall notify communities adjacent to the affected area and the State Department of
Land Conservation and Development prior to any alteration or relocation of a watercourse, and
submit evidence of such notification to the Federal Insurance Administration;
2. The director shall require that maintenance is provided within the altered or relocated portion of a
watercourse so that the flood-carrying capacity is not diminished.
C. Applicable standards and criteria.The approval authority shall apply the standards and criteria provided
in this chapter when reviewing an application for a sensitive lands review.
D. Elevation and floodproofing certification. The approval authority shall require that the elevations and
floodproofing certification required in Subsection 18.510.030.E be provided prior to permit issuance
and verification upon occupancy and final approval.
E. Maintenance of records.
1. Where base flood elevation data is provided through the flood insurance study,the building official
shall obtain and record the actual elevation (in relation to mean sea level) of the lowest floor
(including basement) of all new or substantially improved structures, and whether or not the
structure contains a basement;
2. For all new or substantially improved floodproofed structures,the building official shall:
a. Verify and record the actual elevation(in relation to mean sea level); and
b. Maintain the floodproofing certifications required in this chapter.
Sensitive Lands 18.510-5 Proposed Amendment
Exhibit C
3. The director shall maintain for public inspection all other records pertaining to the provisions in
this chapter.(Ord. 17-22 §2)
18.510.040 General Provisions for Special Flood Hazard Areas
A. Review. The approval authority shall review all applications to determine whether proposed building
sites will minimize the potential for flood damage.
B. Special flood hazard. The areas of special flood hazard identified by FEMA in a scientific and
engineering report entitled "The Flood Insurance Study for Washington County, Oregon and
Incorporated Areas effective October 19, 2018" with accompanying Flood Insurance Map is hereby
adopted by reference and declared to be a part of this ordinance.
C. Base flood elevation data. When base flood elevation data has not been provided in compliance with
Subsection 18.510.040.B, the approval authority shall obtain, review and reasonably utilize any base
flood elevation and floodway data available from a federal, state or other source,in order to administer
Subsections 18.510.040.M and N.
D. Test of reasonableness. Where elevation data is not available either through the flood insurance study
or from another authoritative source,applications for building permits shall be reviewed to assure that
the potential for flood damage to the proposed construction will be minimized. The test of
reasonableness is a local judgment and includes use of historical data,high water marks,photographs
of past flooding, etc., where available. Failure to elevate at least 2 feet above grade in these sensitive
land areas may result in higher insurance rates.
E. Resistant to flood damage.All new construction and substantial improvements,including manufactured
homes, shall be constructed with materials and utility equipment resistant to flood damage.
F. Minimize flood damage. All new construction and substantial improvements, including manufactured
homes,shall be constructed using methods and practices that minimize flood damage.
G. Equipment protection. Electrical, heating, ventilation, plumbing, and air-conditioning equipment and
other service facilities shall be designed or otherwise elevated or located so as to prevent water from
entering or accumulating within the components during conditions of flooding.
H. Water supply systems. All new and replacement water supply systems shall be designed to minimize
or eliminate infiltration of floodwater into the system.
I. Anchoring. All new construction, all manufactured homes and substantial improvements shall be
anchored to prevent flotation,collapse, or lateral movement of the structure.
J. Sanitary sewerage systems. New and replacement sanitary sewerage systems shall be designed to
minimize or eliminate infiltration of floodwater into the systems and discharge from the systems into
floodwater.
K. On-site waste disposal systems.On-site waste disposal systems shall be located to avoid impairment to
them or contamination from them during flooding.
L. Residential construction.
Sensitive Lands 18.510-6 Proposed Amendment
Exhibit C
1. New construction and substantial improvement of any residential structure,including manufactured
homes,shall have the lowest floor,including the basement,elevated at least 1 foot above base flood
elevation;
2. Fully enclosed areas below the lowest floor that are subject to flooding are prohibited, or shall be
designed to automatically equalize hydrostatic flood forces on exterior walls by allowing for the
entry and exit of floodwater. Designs for meeting this requirement shall either be certified by a
registered professional engineer or architect, or shall meet or exceed the following minimum
criteria:
a. A minimum of 2 openings having a total net area of not less than 1 square inch for every square
foot of enclosed area subject to flooding shall be provided;
b. The bottom of all openings shall be no higher than 1 foot above grade;and
c. Openings may be equipped with screens,louvers, or other coverings or devices,provided that
they permit the automatic entry and exit of flood waters.
3. Manufactured homes shall be securely anchored to an adequately anchored permanent foundation
system to prevent flotation,collapse,and lateral movement during the base flood.Anchoring methods
may include,but are not limited to,use of over-the-top or frame ties to ground anchors. Electrical
crossover connections shall be a minimum of 12 inches above base flood elevation.
M. Nonresidential construction. New construction and substantial improvement of any commercial,
industrial, or other nonresidential structure shall either have the lowest floor, including basement,
elevated to the level of the base flood elevation,or together with attendant utility and sanitary facilities,
shall:
1. Be floodproofed so that below the base flood level the structure is watertight with walls
substantially impermeable to the passage of water;
2. Have structural components capable of resisting hydrostatic and hydrodynamic loads and effects
of buoyancy;
3. Be certified by a registered professional engineer or architect that the design and methods of
construction are in compliance with accepted standards of practice for meeting provisions of this
subsection based on their development or review of the structural design,specifications and plans.
Such certifications shall be provided to the building official as provided in 18.510.030.E.2;and
4. Nonresidential structures that are elevated, not floodproofed, shall meet the same standards for
space below the lowest floor as described in Paragraph 18.510.040.L.2.Applicants flood-proofing
nonresidential buildings shall be notified that flood insurance premiums will be based on rates that
are 1 foot below the floodproofed level(e.g., a building constructed to the base flood level will be
rated as 1 foot below that level).
N. Subdivisions and partitions in special flood hazard areas. Subdivisions and partitions in the special
flood hazard area shall meet the following criteria:
1. The design shall minimize the potential for flood damage;
2. Public utilities and facilities such as sewer, gas, electrical,and water systems shall be located and
constructed so as to minimize flood damage;
Sensitive Lands 18.510-7 Proposed Amendment
Exhibit C
3. Adequate drainage shall be provided to reduce exposure to flood damage; and
4. For subdivisions or partitions that contain more than 50 lots or 5 acres and where base flood
elevation data is not available from the Federal Emergency Management Agency (FEMA) or
another authoritative source,the applicant shall generate base flood elevation data to be reviewed
as part of the application.
0. Recreational vehicles.Recreational vehicles placed on sites within Zones Al-A30,AH,and AE on the
flood insurance rate map either:
1. Are on the site for fewer than 180 consecutive days;
2. Are fully licensed and ready for highway use:
a. Are on wheels or jacking system,
b. Are attached to the site only by quick disconnect type utilities and security devices, and have
no permanently attached additions,or
c. Meet the requirements of Subsections 18.510.040.E,F,I,and L and the elevation and anchoring
requirements for manufactured homes.
P. Critical facilities. Construction of new critical facilities shall be,to the extent possible,located outside
of the limits of the special flood hazard area.Construction of new critical facilities shall be permissible
within the special flood hazard area if no feasible alternative site is available. Critical facilities
constructed within the special flood hazard area shall have the lowest floor elevated 3 feet above base
flood elevation or to the height of the 500-year flood, whichever is higher. Access to and from the
critical facility should also be protected to the height utilized above. Floodproofing and sealing
measures shall be taken to ensure that toxic substances will not be displaced by or released into
floodwaters.Access routes elevated to or above the level of the base flood elevation shall be provided
to all critical facilities to the extent possible.
Q. Severability. If any section, clause, sentence, or phrase of the ordinance is held to be invalid or
unconstitutional by any court of competent jurisdiction, then said holding shall in no way affect the
validity of the remaining portions of this chapter.
R. Definitions. The following definitions are only applicable to this section:
1. Basement-Any area of the building having its floor subgrade(below ground level)on all sides.
2. Development - Any man-made change to improved or unimproved real estate, including but not
limited to buildings or other structures, mining, dredging, filling, grading, paving, excavation or
drilling operations or storage of equipment or materials.
3. Elevated Building — For insurance purposed, a non-basement building and that has its lowest
elevated floor raised above ground level by foundation walls, shear walls, posts, piers, pilings, or
columns.
4. Flood Insurance Rate Map (FIRM) means an - The official map of a community, on which the
Federal Insurance Administrator has delineated both the special hazard areas and the risk premium
Sensitive Lands 18.510-8 Proposed Amendment
Exhibit C
zones applicable to the community. A FIRM that has been made available digitally is called a
Digital Flood Insurance Rate Map(DFIRM).
5. Flood Insurance Study(FIS) -The official report provided by the Federal Insurance Administration
that includes flood profiles, the Flood Boundary-Floodway Map, and the water surface elevation
of the base flood.
6. Lowest Floor- The lowest floor of the lowest enclosed area(including basement). An unfinished
or flood resistant enclosure, usable solely for parking of vehicles, building access or storage in an
area other than a basement area is not considered a building's lowest floor; Provided, that such
enclosure is not built so as to render the structure in violation of the applicable non-elevation design
requirements of Section 60.3.
7. Manufactured Home - A structure, transportable in one or more sections, which is built on a
permanent chassis and is designed for use with or without a permanent foundation when attached
to the required utilities.The term"manufactured"home does not include a"recreational vehicle."
8. Manufactured Home Park or Subdivision-A parcel(or contiguous parcels)of land divided into
two or more manufactured home lots for rent or sale.
9. New Construction-For the purposes of determining insurance rates,structures for which the"start
of construction"commenced on or after the effective date of an initial FIRM or after December 31,
1974, whichever is later, and includes any subsequent improvements to such structures. For
floodplain management purposes, new construction means structures for which the start of
construction commenced on or after the effective date of a floodplain management regulation
adopted by a community and includes any subsequent improvements to such structures.
10. Recreational Vehicle-A vehicle which is: (a)Built on a single chassis; (b)400 square feet or less
when measured at the largest horizontal projection; (c) Designed to be self-propelled or
permanently towable by a light duty truck; and(d)Designed primarily not for use as a permanent
dwelling but as temporary living quarters for recreational, camping,travel,or seasonal use.
11. Start of Construction -Includes substantial improvement, and means the date the building permit
was issued, provided the actual start of construction, repair, reconstruction, placement or other
improvement was within 180 days of the permit date. The actual start means either the first
placement of permanent construction of a structure on a site,such as the pouring of slab or footings,
the installation of piles,the construction of columns, or any work beyond the stage of excavation;
or the placement of a manufactured home on a foundation.Permanent construction does not include
land preparation,such as clearing,grading and filling;nor does it include the installation of streets
or walkways; nor does it include excavation for a basement, footings, piers, or foundations or the
erection of temporary forms; nor does it include the installation on the property of accessory
buildings,such as garages or sheds not occupied as dwelling units or not part of the main structure.
For a substantial improvement,the actual start of construction means the first alteration of any wall,
ceiling,floor,or other structural part of a building,whether or not that alteration affects the external
dimensions of the building.
12. Structure-For floodplain management purposes, a walled and roofed building, including a gas or
liquid storage tank,that is principally above ground.
Sensitive Lands 18.510-9 Proposed Amendment
Exhibit C
13. Substantial Damage-Damage of any origin sustained by a structure whereby the cost of restoring
the structure to its before-damaged condition would equal or exceed 50 percent of the market value
of the structure before the damage occurred.
14. Substantial Improvement-Any reconstruction,rehabilitation,addition,or other improvement of a
structure,the cost of which equals or exceeds 50 percent of the market value of the structure
either:
a. Before the"start of construction"of the improvement;or
b. If the structure has been damaged and is being restored,before the damage occurred.
c. The term does not,however, include either:
i. Any project for improvement of a structure to correct existing violations of state or
local health,sanitary,or safety code specifications which have been identified by the
local code enforcement official and which are the minimum necessary to assure safe
living conditions or
ii. Any alteration of a structure listed on the National Register of Historic Places or a State
Inventory of Historic Places,provided that the alteration will not preclude the
structure's designation as a`historic structure'.
15. Violation - The failure of a structure or other development to be fully compliant with the
community's flood plain management regulations. A structure or other development without the
elevation certificate, other certifications, or other evidence of compliance required in Section
60.3(b)(5), (c)(4), (c)(10), (d)(3), (e)(2), (e)(4), or(e)(5) is presumed to be in violation until such
time as that documentation is provided.
S. Disclaimer of liability.This section provides a reasonable degree of flood protection but does not imply
total flood protection.
T. Greater restriction.This section shall not in any way impair or remove the necessity of compliance with
any other applicable laws,ordinances,regulations,etc.Where this section imposes a greater restriction,
the provisions of this section shall control. (Ord. 17-22 §2)
U. New technical data. Notify FEMA within 6 months of project completion when an applicant has
obtained a Conditional Letter of Map Revision(CLOMR) from FEMA, or when development altered
a watercourse, modified floodplain boundaries, or modified Base Flood Elevations. This notification
shall be provided as a Letter of Map Revision(LOMR).
18.510.050 General Provisions for Wetlands
A. Code compliance requirements. Wetland regulations apply to those areas classified as significant on
the City of Tigard"Wetland and Streams Corridors Map,"and to a vegetated corridor ranging from 25
to 200 feet wide, measured horizontally, from the defined boundaries of the wetland, as provided in
"Table 3.1, Vegetated Corridor Widths," and "Appendix C, Natural Resource Assessments," of the
CWS"Design and Construction Standards."Wetland locations may include but are not limited to those
areas identified as wetlands in "Wetland Inventory and Assessment for the City of Tigard, Oregon,"
Fishman Environmental Services, 1994.
B. Delineation of wetland boundaries.Precise boundaries may vary from those shown on wetland maps;
specific delineation of wetland boundaries may be necessary. Wetland delineation will be done by
qualified professionals at the applicant's expense. (Ord. 17-22 §2)
18.510.060 Lapse of Approval
Sensitive Lands 18.510-10 Proposed Amendment
Exhibit C
A. Lapse of approval.Approval of a sensitive lands review shall lapse if:
1. Substantial construction of the approved plan has not begun within a 1.5 year period; or
2. Construction on the site is a departure from the approved plan.
B. Extensions.The director shall,upon written request by the applicant,grant an extension of the approval
period not to exceed 1 year,provided that:
1. No changes are made on the original plan as approved;
2. The applicant can show intent of initiating construction of the site within the 1-year extension
period;and
3. There have been no changes to the applicable comprehensive plan policies and ordinance
provisions on which the approval was based. (Ord. 17-22 §2)
18.510.070 Sensitive Lands Applications
A. Approval required. An applicant, who wishes to develop within a sensitive area, as defined in this
chapter, shall obtain approval in certain situations. Depending on the nature and intensity of the
proposed activity within a sensitive area,either a Type II or Type III review is required,as provided in
Subsections 18.510.020.F and G.The approval criteria for different types of sensitive areas are provided
in Subsections 18.510.070.B—E.
B. Within the special flood hazard area. The approval authority shall approve or approve with conditions
an application for sensitive lands review within the special flood hazard area when all of the following
criteria are met:
1. Compliance with all of the applicable requirements of this title;
2. Land form alterations shall preserve or enhance the special flood hazard area storage function and
maintenance of the zero-foot rise floodway shall not result in any encroachments, including fill,
new construction,substantial improvements and other development unless certified by a registered
professional engineer that the encroachment will not result in any increase in flood levels during
the base flood discharge;
a. If in the floodway and no-rise requirement is met, the development will comply with all
applicable flood hazard reduction provisions.
3. Land form alterations or developments within the special flood hazard area shall be allowed only
in areas designated as commercial or industrial on the comprehensive plan land use map, except
that alterations or developments associated with community service uses,utilities,or public support
facilities shall be allowed on residentially zoned properties subject to applicable zoning standards;
4. Where a land form alteration or development is permitted to occur within the special flood hazard
area it will not result in any increase in the water surface elevation of the 100-year flood;
5. The land form alteration or development plan includes a pedestrian/bicycle pathway in compliance
with the adopted pedestrian/bicycle pathway plan, unless the construction of said pathway is
deemed as untimely;
Sensitive Lands 18.510-11 Proposed Amendment
Exhibit C
6. Pedestrian/bicycle pathway projects within the special flood hazard area shall include a wildlife
habitat assessment that shows the proposed alignment minimizes impacts to significant wildlife
habitat while balancing the community's recreation and environmental educational goals;
7. The necessary U.S. Army Corps of Engineers and State of Oregon Land Board,Division of State
Lands,and CWS permits and approvals shall be obtained;and
8. Where land form alterations or development are allowed within and adjacent to the special flood
hazard area,the city shall require the consideration of dedication of sufficient open land area within
and adjacent to the special flood hazard area in compliance with the comprehensive plan.This area
shall include portions of a suitable elevation for the construction of a pedestrian/bicycle pathway
within the special flood hazard area in compliance with the adopted pedestrian/bicycle pathway
plan.
C. With steep slopes.The approval authority shall approve or approve with conditions an application for
a sensitive lands review on slopes of 25 percent or greater or unstable ground when all of the following
criteria are met:
1. Compliance with all of the applicable requirements of this title;
2. The extent and nature of the proposed land form alteration or development will not create site
disturbances to an extent greater than that required for the use;
3. The proposed land form alteration or development will not result in erosion,stream sedimentation,
ground instability,or other adverse on-site and off-site effects or hazards to life or property;
4. The structures are appropriately sited and designed to ensure structural stability and proper drainage
of foundation and crawl space areas for development with any of the following soil conditions:
wet/high water table; high shrink-swell capability; compressible/organic; and shallow depth-to-
bedrock; and
5. Where natural vegetation has been removed due to land form alteration or development,the areas
not covered by structures or impervious surfaces will be replanted to prevent erosion in compliance
with Chapter 18.320,Landscaping and Screening.
D. Within drainageways. The approval authority shall approve or approve with conditions an application
for a sensitive lands review within drainageways when all of the following criteria are met:
1. Compliance with all of the applicable requirements of this title;
2. The extent and nature of the proposed land form alteration or development will not create site
disturbances to an extent greater than that required for the use;
3. The proposed land form alteration or development will not result in erosion,stream sedimentation,
ground instability,or other adverse on-site and off-site effects or hazards to life or property;
4. The water flow capacity of the drainageway is not decreased;
Sensitive Lands 18.510-12 Proposed Amendment
Exhibit C
5. Where natural vegetation has been removed due to land form alteration or development,the areas
not covered by structures or impervious surfaces will be replanted to prevent erosion in compliance
with Chapter 18.320,Landscaping and Screening;
6. The drainageway will be replaced by a public facility of adequate size to accommodate maximum
flow in compliance with Clean Water Services requirements and the city's adopted stormwater
master plan;
7. The necessary U.S.Army Corps of Engineers and State of Oregon Land Board, Division of State
Lands, and CWS approvals shall be obtained;
8. Where land form alterations or development are allowed within and adjacent to the special flood
hazard area,the city shall require the consideration of dedication of sufficient open land area within
and adjacent to the special flood hazard area in compliance with the comprehensive plan.This area
shall include portions of a suitable elevation for the construction of a pedestrian/bicycle pathway
within the special flood hazard area in compliance with the adopted pedestrian bicycle pathway
plan.
E. Within wetlands.The approval authority shall approve or approve with conditions an application for a
sensitive lands review within wetlands when all of the following criteria are met:
1. Compliance with all of the applicable requirements of this title;
2. The proposed land form alteration or development is neither on wetland in an area designated as
significant wetland on the comprehensive plan special flood hazard area and wetland map nor is
within the vegetative corridor as provided in "Table 3.1 Vegetative Corridor Widths" and
"Appendix C:Natural Resources Assessments"of the CWS"Design and Construction Standards,"
for such a wetland;
3. The extent and nature of the proposed land form alteration or development will not create site
disturbances to an extent greater than the minimum required for the use;
4. Any encroachment or change in on-site or off-site drainage that would adversely impact wetland
characteristics have been mitigated;
5. Where natural vegetation has been removed due to land form alteration or development, erosion
control provisions of the Surface Water Management program of Washington County shall be met
and areas not covered by structures or impervious surfaces will be replanted in like or similar
species in compliance with Chapter 18.320,Landscaping and Screening;
6. All other sensitive lands requirements of this chapter have been met;
7. The necessary U.S.Army Corps of Engineers and State of Oregon Land Board, Division of State
Lands,and CWS approvals shall be obtained;
8. The provisions of Chapter 18.520,Urban Forestry,shall be met;
9. Physical limitations and natural hazards, special flood hazard area and wetlands,natural areas,and
parks, recreation and open space policies of the comprehensive plan have been met. (Ord. 17-22
§2)
Sensitive Lands 18.510-13 Proposed Amendment
Exhibit C
18.510.080 Special Provisions within Locally Significant Wetlands and Along the Tualatin
River,Fanno Creek,Ball Creek,and the South Fork of Ash Creek
A. In order to address the requirements of Statewide Planning Goal 5 (Natural Resources) and the safe
harbor provisions of the Goal 5 administrative rule (OAR 666-023-0030) pertaining to wetlands, all
wetlands classified as significant on the City of Tigard "Wetlands and Streams Corridors Map" are
protected.No land form alterations or developments are allowed within or partially within a significant
wetland, except as allowed/approved in compliance with Section 18.510.120.
B. In order to address the requirements of Statewide Planning Goal 5 (Natural Resources) and the safe
harbor provisions of the Goal 5 administrative rule (OAR 660-023-0030) pertaining to riparian
corridors, a standard setback distance or vegetated corridor area, measured horizontally from and
parallel to the top of the bank, is established for the Tualatin River,Fanno Creek,Ball Creek,and the
South Fork of Ash Creek.
1. The standard width for "good condition" vegetated corridors along the Tualatin River is 75 feet,
unless wider in compliance with CWS "Design and Construction Standards," or modified in
compliance with Section 18.510.120. If all or part of a locally significant wetland (a wetland
identified as significant on the City of Tigard"Wetlands and Streams Corridors Map")is located
within the 75-foot setback area, the vegetated corridor is measured from the upland edge of the
associated wetland.
2. The standard width for"good condition"vegetated corridors along Fanno Creek,Ball Creek, and
the South Fork of Ash Creek is 50 feet, unless wider in compliance with CWS "Design and
Construction Standards," or modified in compliance with Section 18.510.120. If all or part of a
locally significant wetland(a wetland identified as significant on the City of Tigard"Wetlands and
Streams Corridors Map") is located within the 50-foot setback area, the vegetated corridor is
measured from the upland edge of the associated wetland.
3. The minimum width for"marginal or degraded condition"vegetated corridors along the Tualatin
River, Fanno Creek, Ball Creek, and the South Fork of Ash Creek is 50 percent of the standard
width,unless wider in compliance with CWS"Design and Construction Standards,"or modified in
compliance with Section 18.510.120.
4. The determination of corridor condition shall be based on the natural resource assessment
guidelines as provided in the CWS"Design and Construction Standards."
5. The standard setback distance or vegetated corridor area applies to all development proposed on
property located within or partially within the vegetated corridors,except as allowed below:
a. Roads, pedestrian or bike paths crossing the vegetated corridor from one side to the other in
order to provide access to the sensitive area or across the sensitive area,as approved by the city
in compliance with Section 18.510.070 and by CWS"Design and Construction Standards";
b. Utility/service provider infrastructure construction (i.e. storm, sanitary sewer, water, phone,
gas,cable, etc.), if approved by the city and CWS;
c. A pedestrian or bike path, not exceeding 10 feet in width and in compliance with the CWS
"Design and Construction Standards";
d. Grading for the purpose of enhancing the vegetated corridor,as approved by the city and CWS;
Sensitive Lands 18.510-14 Proposed Amendment
Exhibit C
e. Measures to remove or abate hazards,nuisances,or fire and life safety violations,as approved
by the regulating jurisdiction;
f. Enhancement of the vegetated corridor for water quality or quantity benefits, fish, or wildlife
habitat, as approved by the city and CWS;
g. Measures to repair, maintain, alter, remove, add to, or replace existing structures, roadways,
driveways, utilities, accessory uses, or other developments provided they are in compliance
with city and CWS regulations, and do not encroach further into the vegetated corridor or
sensitive area than allowed by the CWS"Design and Construction Standards."
6. Land form alterations or developments located within or partially within the Goal 5 safeharbor
setback or vegetated corridor areas established for the Tualatin River, Fanno Creek, Ball Creek,
and the South Fork of Ash Creek that meet the jurisdictional requirements and permit criteria of
the CWS, U.S. Army Corps of Engineers, Department of State Lands, or other federal, state, or
regional agencies,are not subject to this subsection B,except where the:
a. Land form alterations or developments are located within or partially within a good condition
vegetated corridor,as provided in Paragraphs 18.510.080.B.1 and 2;
b. Land form alterations or developments are located within or partially within the minimum
width area established for marginal or a degraded condition vegetated corridor, as provided in
Paragraph 18.510.080.B.3.
These exceptions reflect instances of the greater protection of riparian corridors provided by the
safe harbor provisions of the Goal 5 administrative rule. (Ord. 17-22 §2)
18.510.090 Adjustments to Base Zone Standards
A. Adjustment. The approval authority may approve up to 50 percent adjustment to any dimensional
standard (e.g., setback, height or lot area) of the base zone to allow development when necessary to
further the purpose of this chapter.The purpose of the adjustment process is to reduce adverse impacts
on wetlands, stream corridors, fish and wildlife habitat, water quality and the potential for slope of
flood hazards. The approval authority may impose any reasonable condition necessary to mitigate
identified impacts resulting from development on otherwise unbuildable land.
B. Adjustment criteria. A special adjustment to the standards in the applicable base zone is processed
through a Type II procedure,as provided in Section 18.710.060,when development is proposed within
or adjacent to the vegetated corridor area or within or adjacent to areas designated as"strictly limit"or
"moderately limit"on the City of Tigard"Significant Habitat Areas Map."Verification of significant
habitat boundaries shall be done in compliance with the procedures provided in Section 18.510.130.
The approval authority shall approve or approve with conditions adjustments when all the following
are met:
1. The adjustment is the minimum necessary to allow a permitted use, while at the same time
minimizing disturbance to a water resource,riparian setback area or water quality buffer;
2. Explicit consideration has been given to maximizing vegetative cover,minimizing excavation and
minimizing impervious surface area on buildable land;
Sensitive Lands 18.510-15 Proposed Amendment
Exhibit C
3. Design options have been considered to reduce the impacts of development, including, but not
limited to, multi-story construction, siting of the residence close to the street to reduce driveway
distance, maximizing the use of native landscaping materials, minimizing parking areas,
minimizing hydrologic impacts and garage space;
4. In no case shall the impervious surface area as a single-family residence (including the building
footprint, driveway and parking areas, accessory structures, swimming pools and patios) exceed
3,000 square feet of a vegetated corridor area;
5. Assurances are in place to guarantee that future development will not encroach further on land
under the same ownership within the vegetated corridor area;
6. Protected vegetated corridor, significant habitat areas and adjacent buffer areas shall be:
a. Placed in a non-buildable tract or protected with a restrictive easement;
b. Restoration and enhancement of habitat and buffer areas required, including monitoring for 5
years. (Ord. 17-22 §2)
18.510.100 Density Transfer and Reductions
A. Density transfer.Density may be transferred from vegetated corridor areas as provided in Sections
18.40.020 and 18.110.040.
B. Density reduction.The minimum number of units required by Chapter 18.110,Residential Zones,
may be waived if necessary to ensure that impacts on habitat areas are minimized.The amount of
reduction in the minimum density shall be calculated by subtracting the number of square feet of
inventoried significant habitat that is permanently protected from the total number of square feet used
to calculate the minimum density requirement. The approval authority may impose any reasonable
condition necessary to mitigate identified impacts resulting from development on otherwise
unbuildable land.
The adjustment shall be processed through a Type II procedure.The approval authority shall approve,
approve with conditions or deny the adjustment provided that the proposal will directly result in the
protection of significant habitat areas through placement in a non-buildable tract or protected with a
restrictive easement. (Ord. 17-22 §2)
18.510.110 Variances to Section 18.510.080 Standards
A. Approval process. Applications for variances from dimensional provisions of this chapter shall be
processed through a Type II procedure,as provided in Section 18.710.060,using the criteria in Chapter
18.790,Variances and Adjustments.
B. Additional criteria. In addition to the variance criteria in Chapter 18.790,Variances and Adjustments,
all the following additional criteria shall be met to grant a variance to any dimensional standard of this
chapter:
1. The variance is necessary to allow reasonable economic use of the subject property,which is owned
by the applicant,and was not created after the effective date of this chapter;
Sensitive Lands 18.510-16 Proposed Amendment
Exhibit C
2. Strict application of the provisions of this chapter would otherwise result in the loss of a buildable
site for a use that is permitted outright in the base zone, and for which the applicant has submitted
a formal application;
3. The applicant has exhausted all options available under this chapter to relieve the hardship;
4. Based on review of all required studies identical to those described in Section 3.02.5.c Tier 2
Alternatives Analysis of the CWS "Design and Construction Standards," the variance is the
minimum necessary to afford relief, considering the potential for increased flood and erosion
hazard, and potential adverse impacts on native vegetation, fish and wildlife habitat, and water
quality;
5. Based on review of all required studies identical to those described in Section 3.02.5 of the CWS
"Design and Construction Standards,"no significant adverse impacts on water quality, erosion or
slope stability will result from approval of this hardship variance, or these impacts have been
mitigated to the greatest extent possible;
6. Loss of vegetative cover shall be minimized. Any lost vegetative cover shall be replaced on-site,
on a square foot for square foot basis,by native vegetation. (Ord. 17-22 §2)
18.510.120 Plan Amendment Option
A. Comprehensive plan amendment. Any owner of property affected by the Goal 5 safeharbor(1)
protection of significant wetlands or(2)vegetated areas established for the Tualatin River,Fanno
Creek,Ball Creek, and the South Fork of Ash Creek may apply for a comprehensive plan amendment
as provided in Chapter 18.795,Map and Text Amendments. This amendment shall be based on a
specific development proposal. The effect of the amendment would be to remove Goal 5 protection
from the property,but not to remove the requirements related to the CWS Stormwater Connection
Permit,which shall be addressed separately through an alternatives analysis,as described in Section
3.02.5 of the CWS"Design and Construction Standards."The applicant shall demonstrate that such
an amendment is justified by either of the following:
B. ESEE analysis. The applicant may prepare an environmental, social, economic and energy (ESEE)
consequences analysis prepared in compliance with OAR 660-23-040.
1. The analysis shall consider the ESEE consequences of allowing the proposed conflicting use,
considering both the impacts on the specific resource site and the comparison with other
comparable sites within the Tigard Planning Area;
2. The ESEE analysis shall demonstrate to the satisfaction of the city council that the adverse
economic consequences of not allowing the conflicting use are sufficient to justify the loss, or
partial loss,of the resource;
3. In particular, ESEE analysis shall demonstrate why the use cannot be located on buildable land,
consistent with the provisions of this chapter, and that there are no other sites within the Tigard
Planning Area that can meet the specific needs of the proposed use;
4. The ESEE analysis shall be prepared by a team consisting of a wildlife biologist or wetlands
ecologist and a land use planner or land use attorney,all of whom are qualified in their respective
fields and experienced in the preparation of Goal 5 ESEE analysis;
Sensitive Lands 18.510-17 Proposed Amendment
Exhibit C
5. If the application is approved, then the ESEE analysis shall be incorporated by reference into the
Tigard Comprehensive Plan,and the"Tigard Wetland and Stream Corridor Map"shall be amended
to remove the site from the inventory.
C. Demonstration of change. In this case,the applicant shall demonstrate that the sensitive area site(s)no
longer meet(s)the applicable significance threshold defined by the Goal 5 administrative rule,relative
to other comparable resources within the Tigard Planning Area.
1. Significance thresholds are described and applied in the addendum to the City of Tigard Local
Wetlands Inventory adopted by reference as part of this chapter.
2. In considering this claim, the city council shall determine that the decline in identified resource
values did not result from a violation of this title.(Ord. 17-22 §2)
18.510.130 Significant Habitat Areas Map Verification Procedures
A. Applicants who concur that the significant habitat areas map is accurate shall submit the following
information to serve as the basis for verifying the boundaries of inventoried habitat areas:
1. Submission requirements.
a. A detailed property description;
b. A scale map of the property showing the locations of significant habitat areas, any existing
built area,wetlands or water bodies,Clean Water Services'vegetated corridor,the special flood
hazard area, the 1996 flood inundation line, and contour lines (2-foot intervals for slope less
than 15 percent and 10-foot intervals for slopes 15 percent or greater);and
c. A current aerial photograph of the property.
2. The approval authority's decision shall be based on consideration of submitted information, site
visit information, and other factual information. Should the applicant disagree with the
determination on the location of significant habitat areas on the property, the precise boundaries
shall be verified by the applicant in compliance with the detailed delineation methodology outlined
in Subsection 18.510.130.B.
B. Applicants who believe that the map is inaccurate shall submit a detailed delineation conducted by a
qualified professional in compliance with the following methodology to verify the precise boundaries
of the inventoried habitat areas by means of a Type II procedure.
1. Verifying boundaries of inventoried riparian habitat.Locating habitat and determining its riparian
habitat class is a 4-step process:
a. Locate the water feature that is the basis for identifying riparian habitat.
i. Locate the top of bank of all streams,rivers,and open water within 200 feet of the property.
ii. Locate the special flood hazard area or 1996 flood inundation line, whichever is greater,
within 100 feet of the property.
Sensitive Lands 18.510-18 Proposed Amendment
Exhibit C
iii. Locate all wetlands within 150 feet of the property. Identified wetlands on the property
shall be further delineated consistent with methods currently accepted by the Oregon
Division of State Lands and the U.S.Army Corps of Engineers.
b. Identify the vegetative cover status of all areas on the property that are within 200 feet of the
top of bank of streams,rivers,and open water,are wetlands or are within 150 feet of wetlands,
and are flood areas and within 100 feet of flood areas.
i. Vegetative cover status shall be as identified on the metro vegetative cover map.
ii. The vegetative cover status of a property may be adjusted only if(a) the property was
developed prior to the time the regional program was approved; or(b)an error was made
at the time the vegetative cover status was determined. To assert the latter type of error,
applicants shall submit an analysis of the vegetative cover on their property using summer
2002 aerial photographs and the following definition of vegetative cover types in Table
18.510.1.
Table 18.510.1
Definitions of Vegetative Cover Types
Typp „ Definition ..
Low structure ve,,etation Areas that are part of a contiguous area 1 acre or larger of grass,meadow,
or open soils croplands,or areas of open soils located within 300 feet of a surface
stream(low structure vegetation areas may include areas of shrub
vegetation less than 1 acre in size if they are contiguous with areas of
grass,meadow,croplands,orchards,Christmas tree farms,holly farms,or
areas of open soils located within 300 feet of a surface stream and
together form an area of 1 acre in size or larger).
Woody vegetation Areas that are part of a contiguous area 1 acre or larger of shrub or open
or scattered forest canopy(less than 60 percent crown closure)located
within 300 feet of a surface stream.
Forest canopy Areas that are part of a contiguous grove of trees 1 acre or larger in area
with approximately 60 percent or greater crown closure, irrespective of
whether the entire grove is within 200 feet of the relevant water feature.
c. Determine whether the degree that the land slope upward from all streams, rivers, and open
water within 200 feet of the property is greater than or less than 25 percent(using the vegetated
corridor measurement methodology as provided in Clean Water Services Design and
Construction Standards;and
d. Identify the riparian habitat classes applicable to all areas on the property using Table 18.510.2
and Table 18.510.3.
Sensitive Lands 18.510-19 Proposed Amendment
Exhibit C
Table 18.510.2
Method for Locating Boundaries of Class I and II Riparian Areas
Distance Development/Vegetation Status[1]
in feet
from Developed areas Woody vegetation
water not providing Low structure vegetation (shrub and scattered Forest canopy(closed
feature !vegetative cover for open soils forest canopy) to open forest canopy)!
Surface streams
0-50 Class II Class I Class I Class I
50-100 Class II [2] Class I Class I
100-150 Class II[2]if slope>25 Class II [2]if slope> Class II [2]
percent 25 percent
150-200 Class II [2]if slope>25 Class II [2]if slope> Class II [2]if slope>
percent 25 percent 25 percent
Wetlands(Wetland feature itself is a Class I Riparian Area)
0-100 Class II [2] Class I Class I
100-150 Class II [2]
Flood Areas(Undeveloped portion of flood area is a Class I Riparian Area)
0-100 I 'Class II[2] 'Class II [2]
[1] The vegetative cover type assigned to any particular area was based on 2 factors:the type of
vegetation observed in aerial photographs and the size of the overall contiguous area of vegetative
cover to which a particular piece of vegetation belonged.As an example of how the categories were
assigned, in order to qualify as a"forest canopy"the forested area had to be part of a larger patch of
forest land at least 1 acre in size.
[2] Areas that have been identified as habitats of concern,as designated on the Metro Habitats of
Concern Map, shall be treated as Class I riparian habitat areas in all cases,subject to the provision of
additional information that establishes that they do not meet the criteria used to identity habitats of
concern as described in Metro's Technical Report for Fish and Wildlife.Examples of habitats of
concern include: Oregon white oak woodlands,bottomland hardwood forests,wetlands,native
grasslands,riverine islands or deltas,and important wildlife migration corridors.
Table 18.510.3
Tualatin Basin"Limit"Decision [11
Conflicting Use Category
Resource Future Urban
Category HighIntensity (2002 and 2004 Nun-Urban
Urban Other Urban additions) Outside lidrn
Class I&II Riparian Inside Moderately Limit Strictly Limit Strictly Limit N/A
Vegetated Corridor
Class I&II Riparian Moderately Limit Moderately Limit Moderately Limit Moderately Limit
Outside Vegetated Corridor
All other Resource Areas Lightly Limit Lightly Limit Lightly Limit Lightly Limit
Inner Impact Area Lightly Limit Lightly Limit Lightly Limit Lightly Limit
Outer Impact Area Lightly Limit Lightly Limit Lightly Limit Lightly Limit
Sensitive Lands 18.510-20 Proposed Amendment
Exhibit C
[1] Vegetated corridor standards are applied consistently throughout the District; in HIU areas they
supersede the"limit"decision.
2. Verifying boundaries of inventoried upland habitat was identified based on the existence of
contiguous patches of forest canopy, with limited canopy openings. The "forest canopy"
designation is made based on analysis of aerial photographs as part of determining the vegetative
cover status of land within the region. Upland habitat shall be as identified on the Significant
Habitat Areas Map unless corrected as provided in this subsection.
a. The only allowed corrections to the vegetative cover status of a property area as follows:
i. To correct errors made when the vegetative status of an area was determined based on
analysis of the aerial photographs used to inventory the habitat. The perimeter of an area
delineated as"forest canopy"on the Metro Vegetative Cover Map may be adjusted to more
precisely indicate the dripline of the trees within the canopied area provided that no areas
providing greater than 60 percent canopy crown closure are de-classified from the"forest
canopy" designation. To assert such errors, applicants shall submit an analysis of the
vegetative habitat cover on their property using the aerial photographs that were used to
inventory the habitat and the definitions of the different vegetative cover types provided in
Table 18.510.1;and
ii. To remove tree orchards and Christmas tree farms from inventoried habitat; provided,
however, that Christmas tree farms where the trees were planted prior to 1975 and have
not been harvested for sale as Christmas trees shall not be removed from the habitat
inventory.
b. If the vegetative cover status of any area identified as upland habitat is corrected in compliance
with Subparagraph 18.510.130.B.2.a to change the status of an area originally identified as
"forest canopy,"then such area shall not be considered upland habitat unless it remains part of
a forest canopy opening less than 1 acre in area completely surrounded by an area of contiguous
forest canopy. (Ord. 17-22 §2) ■
Sensitive Lands 18.510-21 Proposed Amendment