HomeMy WebLinkAboutOrdinance No. 26-12 CITY OF TIGARD, OREGON
TIGARD CITY COUNCIL
ORDINANCE NO. 26-12
AN ORDINANCE ADOPTING AN AMENDMENT TO THE WATER SYSTEM MASTER PLAN AS A SUB-ELEMENT
OF THE CITY'S COMPREHENSIVE PLAN
WHEREAS, the City of Tigard owns and operates a public water system which supplies potable water to
residents, businesses,and public institutions within the Tigard Water Service Area(TWSA).The TWSA includes
approximately two-thirds of the City of Tigard, the City of Durham, the City of King City, and areas of
unincorporated Washington County on Bull Mountain; and
WHEREAS, the City currently has a Water System Master Plan that was adopted by City Council (Resolution
20-62) on December 8, 2020; and
WHEREAS, ORS 197.175 requires cities to prepare,adopt,and implement Comprehensive Plans consistent
with statewide planning goals adopted by the Land Conservation and Development Commission; and
WHEREAS, ORS 197.712 (2)(e) requires cities to develop and adopt a public facilities plan for areas within
the Urban Growth Boundary containing a population greater than 2,500 persons, including rough cost
estimates for projects needed to provide sewer, water, and transportation uses contemplated in the
Comprehensive Plan and Land Use Regulations; and
WHEREAS, the City of Tigard is obligated to supply drinking water to the City of King City per a 2014
Intergovernmental Agreement; and
WHEREAS, the City of King City annexed the Kingston Terrace area west of King City in 2024; and
WHEREAS, the City of Tigard has an existing Water System Master Plan that does not include the
Kingston Terrace Area;and
WHEREAS, the City of Tigard has completed a Water System Plan Addendum specific to the Kingston
Terrace Area, meeting the state requirements for public facility planning; and
WHEREAS, water public facility projects have been identified as part of the Kingston Terrace Water
System Plan Addendum;and
WHEREAS, these projects are appropriate and necessary additions to the City of Tigard Water System
Master Plan; and
WHEREAS, the City of Tigard may desire to use water system development charges to fund part or all of
these projects; and
ORDINANCE NO. 26- 1 Z
Page 1
WHEREAS, on February 11, 2026, the Water Advisory Board approved a motion recommending to City
Council that the Kingston Terrace Water System Plan Addendum be adopted as part of the Water System
Master Plan;and
WHEREAS, on April 26, 2026 the Planning Commission unanimously approved a motion recommending to
City Council that the Kingston Terrace Water System Plan Addendum be adopted as part of the Water System
Master Plan;and
NOW, THEREFORE, THE CITY OF TIGARD ORDAINS AS FOLLOWS:
SECTION 1: The Kingston Terrace Water System Plan Addendum is hereby adopted as part of the City
of Tigard Water System Master Plan.A copy of the Kingston Terrace Water System Plan
Addendum is attached hereto as Exhibit A and incorporated herein as reference.
SECTION 2: The Tigard City Council adopts the "Planning Commission Recommendation to City
Council" (CPA2026-0001) as findings in support of this decision; a copy of the
recommendation is attached hereto as Exhibit B and incorporated herein as reference.
SECTION 2: The projects identified in the Kingston Terrace Water System Plan Addendum will be
eligible for funding from water system development charges collected in the Tigard
Water Service Area as allowed under section 3.24.060 of the Tigard Municipal Code.
SECTION 3: This ordinance shall be effective 30 days after its passage by the council,signature by the
mayor, and posting by the city recorder.
PASSED: By ti \Ufl rc O'S vote of all council members present after being read by number
and title only,this 2(o1" day of M a) , 2026
Lindsay Bartholomew, Deputy City Recorder
APPROVED: By Tigard City Council this 247"' day of Mal , 2026.
r• -- ---7.2?
Yi-Ka Hu, Mayor
Approved as to form:
/
City Attorney
c J aL 1 0.0 L2.
Date
ORDINANCE NO. 26-12,
Page 2
Exhibit A
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TIGARD
CITY OF TIGARD
Kingston Terrace Water System Plan Addendum
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Addendum to 2020 Water System Plan
FINAL/July 2024
REDACTED COPY
Certain portions of this document that locate or
describe critical drinking water system
infrastructure have been redacted for security r/
purposes in accordance with ORS 192 .355 (33) . dicar11lo
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TIGARD
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CITY OF TIGARD
Kingston Terrace Water System Plan Addendum
Addendum to 2020 Water System Plan
FINAL/July 2024
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ADDENDUM TO 2020 WATER SYSTEM PLAN
JULY 2024/FINAL/CAROLLO
Contents
SECTION 1 INTRODUCTION 1
1.1 Kingston Terrace Overview 1
SECTION 2 PLANNING CRITERIA 1
2.1 Storage Requirements 1
2.2 Supply Requirements 1
2.3 Pumping Requirements 1
2.4 Fire Flow Requirements 2
2.5 Future Pipeline Requirements 2
SECTION 3 DEMAND PROJECTIONS 2
3.1 Residential Densities and Buildout Development Assumptions 3
3.2 Kingston Terrace Buildout Units 3
3.3 Summary of Water Demand Projections 5
SECTION 4 HYDRAULIC MODEL UPDATES AND NEW SCENARIOS 5
4.1 Hydraulic Model Updates 6
4.2 New Model Scenarios 8
SECTION 5 SYSTEM ANALYSIS 8
5.1 Storage Analysis 8
5.1.1 Storage Analysis Conclusions 10
5.2 Supply and Pumping Analysis 10
5.2.1 Supply Analysis 10
5.2.2 Pumping Analysis 12
5.3 Hydraulic Model Analysis 13
5.3.1 Kingston Terrace 2030 ADD 13
5.3.2 Kingston Terrace 2040 PHD 15
5.3.3 Kingston Terrace 2040 MDD + FF 17
5.3.4 Kingston Terrace Buildout PHD 20
5.3.5 Kingston Terrace Buildout MDD + FF 22
5.3.6 Hydraulic Model Analysis Conclusions 25
SECTION 6 RECOMMENDED IMPROVEMENTS 25
6.1 Storage 25
6.2 Supply and Pumping 26
6.3 Pipeline Network 26
CITY OF TIGARD
KINGSTON TERRACE WATER SYSTEM PLAN ADDENDUM
pw:llCarollo/ORITigardl201813-000000103 Reports and Studies/02 Deliverables/Addendum to 2020 WSPlAddendum_2020WSP
ADDENDUM TO 2020 WATER SYSTEM PLAN
JULY 2024/FINAL/CAROLLO
SECTION 7 COST ESTIMATES 28
7.1 Storage Cost Estimates 28
7.2 Supply and Pumping Cost Estimates 29
7.2.1 Pipeline Cost Estimates 30
7.2.2 Total Cost Estimates 30
Appendices
APPENDIX A SUPPORTING DOCUMENTS FROM KING CITY AND CONSULTANT
Tables
Table 1 Storage Component Requirements 1
Table 2 Water Demand Projection Assumptions from 2020 WSP 2
Table 3 Residential Assumptions 3
Table 4 Kingston Terrace Development Phase Assumptions 4
Table 5 Kingston Terrace Demand Projections 5
Table 6 Summary of Kingston Terrace Demands by Planning Year 5
Table 7 Existing Available Storage in the 410 PZ 9
Table 8 Storage Analysis—Scenario A 9
Table 9 Storage Analysis—Scenario B 10
Table 10 Storage Analysis Summary 10
Table 11 Existing Supply Capacity 11
Table 12 Supply Analysis 11
Table 13 Existing Pumping Capacity 12
Table 14 Pumping Analysis 12
Table 15 Summary of Pipeline Network to serve Kingston Terrace 26
Table 16 H-W Indices of Water Utility Construction in the Pacific Region 28
Table 17 Storage Project Cost Estimates 29
Table 18 Pipeline Cost Estimates 30
Table 19 Total Cost Estimates 31
Figures
Figure 1 Water Service Area Map 2
Figure 2 Pressure Zones 2
Figure 3 Kingston Terrace Phases 4
Figure 4 Hydraulic Model Updates 7
Figure 5 Kingston Terrace—Maximum Pressures under 2030 ADD Conditions 14
Figure 6 Kingston Terrace—Minimum Pressures under 2040 PHD Conditions 16
Figure 7 Kingston Terrace—2040 Fire Flow Requirements 18
Figure 8 Kingston Terrace—Residual Pressures under 2040 MDD + FF Conditions 19
Figure 9 Kingston Terrace—Minimum Pressures under Buildout PHD Conditions 21
Figure 10 Kingston Terrace—Buildout Fire Flow Requirements 23
Figure 11 Kingston Terrace—Residual Pressures under Buildout MDD + FF Conditions 24
Figure 12 Kingston Terrace—Recommended Buildout Transmission Pipeline Network 27
CITY OF TIGARD
KINGSTON TERRACE WATER SYSTEM PLAN ADDENDUM ii
ADDENDUM TO 2020 WATER SYSTEM PLAN
JULY 2024/FINAL/CAROLLO
Abbreviations
2020 WSP City of Tigard's 2020 Water System Master Plan
ADD average day demand
ASR aquifer storage and recovery
City City of Tigard
EPS extended period simulation
FF fire flow
fps feet per second
gpd gallons per day
gpm gallons per minute
HGL hydraulic grade line
King City City of King City
LF linear feet
LOT Lake Oswego Tigard Partnership
MDD maximum day demand
MG million gallons
mgd million gallons per day
PHD peak hour demand
PRV pressure reducing valves
psi pounds per square inch
PZ pressure zone
URA Urban Reserve Area
WTP water treatment plant
CITY OF TIGARD
KINGSTON TERRACE WATER SYSTEM PLAN ADDENDUM ill
ADDENDUM TO 2020 WATER SYSTEM PLAN
JULY 2024/FINAL/CAROLLO
SECTION 1 INTRODUCTION
This document is an addendum to the City of Tigard's (City) 2020 Water System Master Plan, now referred
to as the 2020 Water System Plan (WSP).
Since the City adopted the WSP in 2020,the City of King City(King City) has launched the Kingston
Terrace Master Plan,an effort to guide future growth and development in the 528-acre Kingston Terrace
area.The City currently supplies water to King City,and the Kingston Terrace area,which will be within
King City,will also be served by the City.
This addendum documents the development of demand projections for Kingston Terrace,analysis of
pumping, supply, and storage capacity,and the recommendations for a pipeline network to serve the
area.
This addendum does not update the 2020 WSP for any part of the water system outside Kingston Terrace.
1.1 Kingston Terrace Overview
In the 2020 WSP,the Kingston Terrace area is identified as King City West(Urban Reserve Area [URA] 6D),
as shown in Figure 1 (Figure 1-1 from the 2020 WSP).The area is bounded by the current King City limits
to the east, Beef Bend Road on the north,the Tualatin River/Elsner Road on the south, and Roy Rogers
Road to the west.
The City's service area is split into pressure zones(PZ)to serve customers at different hydraulic grade
lines(HGL)as shown in Figure 2 (Figure 1-3 from the WSP). Kingston Terrace will be part of the City's
410 pressure zone.
King City and its consultants have provided the City with detailed plans for developing the Town Center,
in the northwest portion of Kingston Terrace,and general development characteristics for the remaining
area.
CITY OF TIGARD
KINGSTON TERRACE WATER SYSTEM PLAN ADDENDUM 1
ADDENDUM TO 2020 WATER SYSTEM PLAN
JULY 2024/FINAL/CAROLLO
Figure 1 Water Service Area Map
•Legend L" <i i
���Future Service Area
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v1 t 560G 360E 1,
530 410 I
580A a 660H I1
4'1 �� King Cityng City if �.
410 Durham • I
Source:2020 WSP
Figure 2 Pressure Zones
CITY OF TIGARD
KINGSTON TERRACE WATER SYSTEM PLAN ADDENDUM 2
ADDENDUM TO 2020 WATER SYSTEM PLAN
JULY 2024/FINAL/CAROLLO
SECTION 2 PLANNING CRITERIA
This section summarizes the planning criteria outlined in the 2020 WSP,including storage, pumping,fire
flow(FF), and future pipeline requirements,which will be used to evaluate providing water service to
Kingston Terrace.
2.1 Storage Requirements
The City's 2020 WSP defines criteria for assessing adequate storage capacity in each of the pressure zones
in the following four storage components:
• Operational storage:volume of water between the on and off set points for the supply sources under
normal conditions.
• Equalizing storage:volume of water dedicated to supplying demand fluctuations throughout the day.
• Fire suppression storage:volume of water stored to meet the single most severe FF demand within
each pressure zone.
• Emergency Storage:volume of water stored to supply water during emergencies such as pipeline
failures, equipment failures, power outages, or natural disasters.
Table 1 summarizes the requirements for each storage component.
Table 1 Storage Component Requirements
Storage Component Volume Requirement
Operational Storage 'Based on tank level set points.
Equalizing Storage 25 percent of MDD
Fire Suppression Storage Required FF times flow duration-3,000 gpm for 3 hours,or 0.54 MG for the 410 PZ
Emergency Storage 2 times ADD
Notes:
ADD-average day demand;gpm-gallons per minute;MDD-maximum day demand;MG-million gallons.
2.2 Supply Requirements
The City's 2020 WSP defines the supply system criteria as having supply capacity to provide MDD to the
system.The supply system must also be capable of providing ADD plus water for aquifer storage
recovery(ASR) recharge from only the Lake Oswego Tigard Partnership(LOT)Water Treatment
Plant(WTP)during the off-peak seasons(late January to mid-May).
2.3 Pumping Requirements
The City's pumping capacity requirements vary depending on pressure zone infrastructure.The pumping
requirement applicable to the 410 PZ from the 2020 WSP is the"pumping to storage requirement",where
the firm pumping capacity should be equal to the pressure zone's MDD. Firm pumping capacity is defined
as a pump station's pumping capacity with the largest pump out-of-service.When there are multiple
pump stations serving the same zone,firm capacity is considered as the combined capacity with only the
largest pump out-of-service, rather than the largest pump at each station out-of-service.
CITY OF TIGARD
KINGSTON TERRACE WATER SYSTEM PLAN ADDENDUM 1
ADDENDUM TO 2020 WATER SYSTEM PLAN
JULY 2024/FINAL/CAROLLO
2.4 Fire Flow Requirements
As outlined in the 2020 WSP,the City's FF requirements are based on land use type as summarized below:
• Single family and duplex residential:1,500 gpm for two hours.
• Medium density residential, neighborhood, and community services:2,500 gpm for two hours.
• High-density residential,commercial,industrial.,and institutional:3,000 gpm for three hours.
2.5 Future Pipeline Requirements
The 2020 WSP states that the City's acceptable service pressure range under normal operating
conditions(ADD) is 40 to 80 pounds per square inch (psi).However, due to ground elevations in some
pressure zones,some customers receive service pressures outside this range.Service pressures should
maintain a minimum pressure of 30 psi under peak hour demand (PHD) conditions.Where mainline
pressures exceed 80 psi, services are equipped with individual pressure reducing valves(PRV)to maintain
their static pressures at no more than 80 psi.
During an FF event or emergency,the minimum service pressure is 20 psi as required by Oregon Health
Authority,Drinking Water Program regulations.
The pressure requirements evaluated in this addendum are summarized below:
• Maximum pressure during ADD:80 psi.
• Minimum pressure during PHD: 30 psi.
• Residual pressure during MDD + FF:20 psi.
The 2020 WSP also states the velocity requirement for distribution mains as not to exceed 10 feet per
second(fps) during PHD or FF.Any new water main distribution mains should be at least 8 inches in
diameter to supply minimum FFs.
SECTION 3 DEMAND PROJECTIONS
The water demand projections developed for this addendum follow the demand projection methodology
outlined in the 2020 WSP.The water demand projection assumptions from the 2020 WSP used to
estimate demands for Kingston Terrace are summarized in Table 2.
Table 2 Water Demand Projection Assumptions from 2020 WSP
Component I Assumption
Water use per person 90_gallons per capita per day
Persons per household(1) 2.46
Irrigation demand 5 percent of residential water demand
Water use per commercial customer 1,125 gallons per day(gpd)
Non-revenue water 8percent of water
MDD:ADD peaking factor 1.96
PHD:MDD peaking factor 2
Notes:
(1) The 2020 WSP provided a range of persons per household from 2.39 to 2.46.The value 2.46 was selected as it is the most
conservative assumption.
CITY OF TIGARD
KINGSTON TERRACE WATER SYSTEM PLAN ADDENDUM 2
ADDENDUM TO 2020 WATER SYSTEM PLAN
JULY 2024/FINAL/CAROLLO
3.1 Residential Densities and Buildout Development Assumptions
King City and its consultant provided information that was used to estimate the number of residential,
commercial, and municipal units in Kingston Terrace.The following documents can be found in
Appendix A:
• Site Plan and Phasing Plan for Kingston Terrace Town Center.
• Planned residential densities for areas outside the Town Center(draft code amendments for
Kingston Terrace).
• Buildout Development Assumptions.
• Water Concept Plan for Kingston Terrace Town Center.
• Future Streets Plan.
3.2 Kingston Terrace Buildout Units
The number of residential units for the Town Center were provided on the Site Plan and Phasing Plan for
Kingston Terrace Town Center.The number of commercial and municipal customers were estimated
based on building size.
King City and its consultant provided minimum net densities and the minimum number of units that must
be accommodated by each neighborhood outside the Town Center,which are summarized in Table 3.
Table 3 also includes the percent of land in each neighborhood that was assumed to be developed (to
approximately meet the buildout development assumptions).
Table 3 Residential Assumptions
Town Center Beef Bend !Central Rural Character
Minimum net density assigned to each development 122.6 22 17 13
(units/acre) _ _
Minimum number of units that must be accommodated 1,913 1,315 370 435
by each neighborhood
Percent of land assumed developedr) 85% 75% 30% 30%
Notes:
(1) The percent of land assumed developed varies based on neighborhood and was estimated to approximately meet the
buildout development assumptions for number of residential units.
The Kingston Terrace Town Center was split into Phases 1 through 4.5 for development on the Phasing
Plan for Kingston Terrace Town Center.The remaining areas in Kingston Terrace were split into phases,
based on the neighborhood outlines and assumptions for development order, as shown in Figure 3.
CITY OF TIGARD
KINGSTON TERRACE WATER SYSTEM PLAN ADDENDUM 3
ADDENDUM TO 2020 WATER SYSTEM PLAN
JULY 2024/FINAL/CAROLLO
.
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Figure 3 Kingston Terrace Phases
Table 4 outlines each development phase,the estimated number of residential units, commercial
customers, and municipal customers, and the year the development phase is assumed to be online.
Table 4 Kingston Terrace Development Phase Assumptions
Phase 1Neighborhood Number of Number of Number of Assumed
Residential Units Commercial Customers Municipal Customers Year Online
1 Town Center 1469 136 0 2024
2 Town Center 277 12 40 2028
3 Town Center 289 0 0 2030
4 Town Center 55 0 0 2032
4.5 Town Center 66 0 0 2033
5 Beef Bend 281 4 0 2038
6 Beef Bend 413 0 0 2043
7 Town Center 225 0 0 2048
8 Town Center 311 0 0 2048
9 Beef Bend 413 4 0 2048
10 Beef Bend _ 223 0 0 2048
11 Central 485 0 0 ,2053 _
12 Rural ,495 0 0 2053
CITY OF TIGARD
KINGSTON TERRACE WATER SYSTEM PLAN ADDENDUM 4
ADDENDUM TO 2020 WATER SYSTEM PLAN
JULY 2024/FINAL/CAROLED
3.3 Summary of Water Demand Projections
Using the water demand projection assumptions outlined in Table 2 and the number of units from
Table 4,water demands were projected for Kingston Terrace. Note,the water use per municipal customer
was assumed to be the same as water use per commercial customer(1,125 gpd).
Table 5 shows the projected Kingston Terrace water demands for 2043 and buildout. Note,the projections
for 2043 were included to match the year provided in the buildout development assumptions table
(Appendix A).The buildout water demands for Kingston Terrace are projected to approximately 780 gpm
for ADD and 1,530 gpm for MDD.
The projected ADD, MDD,and PHD for Kingston Terrace by planning year are summarized in Table 6.
Table 5 Kingston Terrace Demand Projections
Component By 2043 Buildout
Residential Units 1,8401') 4,00012i
Commercial and Municipal Customers 96 96
Residential ADD Projection 284 gpm 615 gpm
Commercial and Municipal ADD Projection 72 gpm 75 gpm
Total ADD Projection(3) 400 gpm _ 778 gpm
Total MDD Projection 784 gpm 1,526 gpm
Notes:
(1) Buildout development assumptions from King City estimate 1,788 total residential units by 2043.
(2) Buildout development assumptions from King City estimate 3,576 total residential units by buildout.
3 Includes irrivation demand and non-revenue water.
Table 6 Summary of Kingston Terrace Demands by Planning Year
Demand 2025 2030 12035 2040 2050 Buildout
ADD(gpm) 112 '255 276 328 608 778
MDD(gpm) 220 499 541 643 1,191 1,526
PHD(gpm) 440 998 1,081 1,286 2,382 3,051
SECTION 4 HYDRAULIC MODEL UPDATES AND NEW
SCENARIOS
The City's hydraulic model was developed using Innovyze's InfoWater Pro software for the 2020 WSP.The
model was calibrated to 2018 demand and operation conditions,using FF tests for steady state calibration
and data from the City's Supervisory Control and Data Acquisition system for extended period simulation
(EPS)calibration.
CITY OF TIGARD
KINGSTON TERRACE WATER SYSTEM PLAN ADDENDUM 5
ADDENDUM TO 2020 WATER SYSTEM PLAN
JULY 2024/FINAL/CAROLLO
4.1 Hydraulic Model Updates
The City's hydraulic model was updated for this addendum, but no additional calibration was completed.
Pipeline installed in the City's system between 2018 and 2022 was added to the hydraulic model, as
highlighted in Figure 4. Note, Figure 4 also shows the pipeline on SW 121st Avenue between SW Walnut
Street and SW Fonner Street as a 24-inch-diameter pipeline.This pipeline and the PRV a
were installed in 2023.Operational data, including PRV settings and pump
controls,was then contlrmed in the model.
The City's hydraulic model also included pipeline and junctions with demands to serve URA 6D.These
pipelines were deactivated,and the demands were replaced with demands developed for the
Kingston Terrace Addendum.
CITY OF TIGARD
KINGSTON TERRACE WATER SYSTEM PLAN ADDENDUM 6
ADDENDUM TO 2020 WATER SYSTEM PLAN
UY I_! A
-Figure 4 Hydraulic Model Updates - - _
CITY OF TIUARD
TIGARD KINGSTON TERRACE WATER MASTFR BEAN ADDENDUM
ADDENDUM TO 2020 WATER SYSTEM PLAN
JULY 2024/FINAL/CAROLLO
4.2 New Model Scenarios
After the model was updated,scenarios were created to evaluate service to Kingston Terrace for the 2030
and 2040 planning years to match the existing model scenarios. Pipelines were added to the model to
serve Kingston Terrace based on the phases that would be online by planning year 2030 and planning
year 2040. Demand projections for Kingston Terrace were allocated to junctions for the planning years.
Finally, FF requirements for Kingston Terrace were added based on the proposed land use.
New model scenarios were also added to evaluate Kingston Terrace buildout conditions. Because the
City's model only includes scenarios up to 2040, Kingston Terrace buildout conditions were added to the
2040 system conditions(i.e.,the model was run under 2040 demand and operational conditions for the
rest of the system and buildout pipeline and demands for Kingston Terrace).
The new scenarios created for system analysis, and the purpose of each scenario, are as follows:
• Kingston Terrace 2030 ADD: identify maximum pressures above 80 psi.
• Kingston Terrace 2040 PHD: identify minimum pressure below 30 psi and maximum velocities greater
than 10 fps.
• Kingston Terrace 2040 MDD + FF: identify residual pressures below 20 psi.
• Kingston Terrace Buildout PHD: identify minimum pressure below 30 psi and maximum velocities
greater than 10 fps.
• Kingston Terrace Buildout MDD + FF: identify residual pressures below 20 psi.
The 2030 ADD,2040 PHD, and Buildout PHD scenarios were set to run for seven days in an EPS.The
2040 MDD + FF and Buildout MDD + FF scenarios were set to run in a steady state simulation using the FF
analysis model function.
SECTION 5 SYSTEM ANALYSIS
This section summarizes the storage, pumping, and hydraulic analyses for serving water to Kingston
Terrace.
5.1 Storage Analysis
The storage analysis compared the available storage in the 410 PZ and the required storage components
outlined in Section 2.1.Table 7 summarizes the total volume and operational storage for each reservoir in
the 410 PZ. Since the 2020 WSP,the City has taken Reservoirs 9-1 and 9-2 offline.
CITY OF TIGARD
KINGSTON TERRACE WATER SYSTEM PLAN ADDENDUM 8
ADDENDUM TO 2020 WATER SYSTEM PLAN
JULY 2024/FINAL/CAROLLO
Table 7 Existing Available Storage in the 410 PZ
Reservoir Reservoir Reservoir Reservoir I Reservoir Reservoir Reservoir Reservoir 410 PZ
1-1 1-2 2 3-1 3-2 4 10 13 Total
Total Volume '1.0 1.0 0.3 0.8 2.5 1.0 10.0 3.5 19.8
(MG) _ _ _
Available 1.0 1.0 025 0.75 2.32 0.71 10.0 3.5 19.5
Storage(MG)
Operational 10.28 0.28 0.05 0.27 0.08 0.34 2.30 0.35 3.95
Sbrage(MG)
The City is planning to take Reservoir 2 offline in 2025 and Reservoirs 1-1, 1-2,and 4 offline in 2027.To
maximize the City's existing storage,two storage scenarios were evaluated:
• Scenario A:Continue with existing plan for reservoirs offline.
• Scenario B:Keep all remaining reservoirs online through the planning period.
The storage analyses for Scenarios A and B are summarized in Tables 8 and 9, respectively. Note,the
storage analysis was performed for Kingston Terrace buildout,which is assumed by 2053. Because
the 2020 WSP only includes demand projections up to 2050, Kingston Terrace buildout conditions were
added to the 2050 demand projections to create the"Kingston Terrace Buildout"year.
Table 8 Storage Analysis-Scenario A
Planning Year Reservoirs Online Available Required Storage(MG) Surplus,!
Storage Operational Equalizing Emergency I Fire Total (Deficit)
(MG) IMGj
Existing 1-1,1-2,2,3-1, 19.5 4.0 2.1 8.4 0.54 15.0 4.5
32,4,10,13 11
-
2025 1-1,1-2,3-1, 19.3 3.9 :2.8 11.3 0.54 18.5 0.8
3-2,4,10,13 -
2030 3-1,3-2,10,13 16.6 3.0 3.1 12.5 0.54 19.2 (2.6)
2035 3-1,3-2,10,13 16.6 ,3.0 3.3 - 13.5 0.54 20A (3.8)
2040 3-1,3-2,10,13 16.6 3.0 3.6 14.5 0.54 21.6 (5.1)
2050 34,3-2,10,13 16.6 3.0 4.0 16.7 .0.54 242 (7.7)
Kingston Terrace 3-1,3-2,10,13 116.6 3.0 4.1 17.1 0.54 24.7 (8.1)
Buildoutf2
Notes:
(1) Scenario A:Continue with existing plan for reservoirs taken offline(Reservoir 2 offline in 2025; Reservoirs 1-1,1-2,and 4
offline in 2027).
(2) The Kingston Terrace Buildout year includes buildout demand projections for Kingston Terrace and 2050 demand projections
for the rest of the system.
CITY OF TIGARD
KINGSTON TERRACE WATER SYSTEM PLAN ADDENDUM 9
ADDENDUM TO 2020 WATER SYSTEM PLAN
JULY 2024/FINAL/CAROLLO
Table 9 Storage Analysis—Scenario B
Planning Year Reservoirs Online Available Required Storage(MG) Surplus/
Storage Operational Ecualizing Emergency I Fire Total (Deficit)
Existing 1-1,1-2,2,3-1, 19.5 4.0 12.1 8.4 0.54 15.0 4.5
3-2,4,10,13 _
2025 1-1,1-2,2,3-1, 19.5 4.0 2.8 11.3 0.54 18.6 1.0
3-2,4,10,13
2030 1 1 1-2,2,3-1, 19.5 4.0 3.1 12.54 0.54 20.1 (0.6)
3-2,4,10,13
2035 1-1,1-2,2,3-1, 19.5 4.0 3.3 13.5 0.54 21.3 (1.6)
3-2,4,10, 13
2040 1-1,1-2,2,3-1, 19.5 . 4.0 3.6 14.5 0.54 22.6 (3.1)
3-2,4,10,13
2050 1-1,1-2,2,3-1, 19.5 ,4.0 4.0 16.°7 40.54 252 (5.6)
3-2,4,10,13
Kingston Terrace 1-1,1-2,2,3-1, 19.5 4.0 4.1 17.1 0.54 25.7 (6.1)
Buildoutt2) 3-2,4,10,13
Notes:
(1) Scenario B:All remaining reservoirs are kept online through the planning period.
(2) The Kingston Terrace Buildout year includes buildout demand projections for Kingston Terrace and 2050 demand projections
for the rest of the system.
5.1.1 Storage Analysis Conclusions
With the Citys current schedule for decommissioning reservoirs,new storage would be needed by 2027
to meet the storage requirements in the 410 PZ. If the City does not decommission any other reservoirs
before Kingston Terrace buildout additional storage would not be needed until 2029.Table 10 outlines
the year new storage is needed to meet requirements and the volume of additional storage needed by
Kingston Terrace buildout for the two scenarios with and without Kingston Terrace online.
Table 10 Storage Analysis Summary
Scenario Description Year new storage Additional storage needed
is needed to meet by Kingston Terrace Buildout
requirements (or planning year 2050)
Scenario A Reservoir 2 offline in 2025;Reservoirs 1-1, 1-2, 2027 8.1 MG
and 4 offline in 2027
Scenario B All reservoirs remain online through planning period 2029 6.1 MG
5.2 Supply and Pumping Analysis
5.2.1 Supply Analysis
The supply analysis compared the ADD and MDD to the system firm supply capacity.As stated in the
City's 2020 WSP,the firm system supply capacity is the total supply of all the wells and LOT WTP with the
largest producing ASR well out of service.
CITY OF TIGARD
KINGSTON TERRACE WATER SYSTEM PLAN ADDENDUM 10
ADDENDUM TO 2020 WATER SYSTEM PLAN
JULY 2024/FINAL/CAROLLO
Table 11 summarizes the City's supply capacity.
Table 11 Existing Supply Capacity
Pump Capacity
(mgd)
LOT WTP 14.0
Well2 0.58
ASR 1 1.44
ASR 2 2.00
ASR 3(1) 2.00
Total Supply Capacity 20.0
Total Firm Supply Capacity(2) 18.0
Notes:
(1) ASR 3 is planned to be online in summer 2024.
(2) Capacity with the largest producing ASR Well(ASR 2)out-of-service.
ASR-aquifer storage and recovery;mgd-million galbns per day.
The system supply capacity was evaluated for each planning year, as summarized in Table 12. Note,the
supply analysis was performed for Kingston Terrace buildout,which is assumed by 2053.Because the 2020
WSP only includes demand projections up to 2050, Kingston Terrace buildout conditions were added to
the 2050 demand projections to create the"Kingston Terrace Buildout"year.
Table 12 Supply Analysis
Off-Peak Season Supply Analysis Firm Supply Analysis
Available Off-Peak Requirement- Surplus! Firm Supply Requirement- Surplus!
Planning Year Season Supply Total ADD (Deficit) Capacity+PP Total MDD (Deficit)
Capaciiy'l (mgd) (mgd) (mgd) (mgd) (mgd)
(mgd)
2025 14.0 82 5.8 18.0 16.4 1.6
2030 14.0 18.9 5.1 18.0 18.1 (0.1)
2035 14.0 9.5 4.5 18.0 19.3 (1.3)
2040 14.0 10.1 3.9 18.0 20.6 (2.6)
2050 14.0 11.5 2.5 18.0 23.4 (5.6)
Kingston Terrace 14.0 11.7 2.3 18.0 23.9 (6.1)
Buildout
Notes:
(1) LOT WTP Capacity.
12) Total supply of all the wells and LOT WTP with the largest producing ASR well out of service.
New supply capacity is needed by 2030 when the total MDD with Kingston Terrace is projected to exceed
the total firm supply capacity of 18 mgd. By Kingston Terrace buildout, approximately 6 mgd of additional
firm supply capacity is needed to meet the system supply requirements.
The City has sufficient off-peak season supply capacity to meet the system ADD through the planning
horizon.
CrrY OF TIGARD
KINGSTON TERRACE WATER SYSTEM PLAN ADDENDUM 11
ADDENDUM TO 2020 WATER SYSTEM PLAN
JULY 2024/FINAL/CAROLLO
5.2.2 Pumping Analysis
The pumping analysis compared the required pumping for the 410 PZ to the available pumping capacity.
Because supply to the upper zones is pumped through the 410 PZ,the total system MDD was compared
to the total system firm capacity for the pumping analysis.
Table 13 summarizes the total and firm pumping capacity.
Table 13 Existing Pumping Capacity
Pump Capacity
mgd,
PS 5:Pump 1 3.67
PS 5:Pump 2 3.67
PS 5:Pump 3 3.67
PS 5:Pump 4 3.67
PS 5:Pump 6 4.51
Well 2 0.58
ASR 1 1.44
ASR 2 2.00
ASR 3 2.00
Total Pumping Capadty 25.2
Total Firm Capacityt1) 20.7
Notes:
(1) Capacity with the largest pump(PS 5:Pump 6)out-of-service.
The pumping capacity of the 410 PZ was evaluated for each planning year,as summarized in Table 14.
Note,the pumping analysis was performed for Kingston Terrace buildout,which is assumed by 2053.
Because the 2020 WSP only includes demand projections up to 2050, Kingston Terrace buildout
conditions were added to the 2050 demand projections to create the"Kingston Terrace Buildout"year.
Table 14 Pumping Analysis
Planning Year !Total Firm Capacityoi Maximum Pumping Requirement Surplus/(Deficit)
mgd) Total MDD(mgd) (mgd)
2025 20.7 16.4 4.3
2030 • 20.7 18.1 2.6
2035 20.7 19.3 1 A
2040 20.7 20.6 0.1
2050 20.7 23.4 (2.7)
Kingston Terrace Buildout 20.7 23.9 (3.2)
Notes:
(1) Capacity with the largest pump(PS 5:Pump 6)out-of-service.
New pumping capacity is needed by 2041 when the total MDD with Kingston Terrace is projected to
exceed the total firm pumping capacity of 20.7 mgd.By Kingston Terrace buildout,approximately 3.2 mgd
of additional firm pumping capacity is needed to meet the pumping requirements.
CITY OF TIGARD
KINGSTON TERRACE WATER SYSTEM PLAN ADDENDUM 12
ADDENDUM TO 2020 WATER SYSTEM PLAN
JULY 2024/FINAL/CAROLLO
5.3 Hydraulic Model Analysis
The hydraulic model analysis was performed to review system pressures and velocities and confirm the
pipeline network.This section summarizes the results from each model scenario and the overall model
analysis conclusions.
The alignments for the pipeline networks follow the proposed streets in Kingston Terrace.A more detailed
street plan was provided for the Town Center, so a more detailed pipeline network was developed for the
Town Center(Phases 1 to 4.5).
5.3.1 Kingston Terrace 2030 ADD
The Kingston Terrace 2030 ADD model scenario was used to review maximum pressures under 2030 ADD
conditions with the following assumptions:
▪ Kingston Terrace Phases 1-3 online with 255 gpm in water demands allocated (the existing diurnal
pattern was assigned to the model junctions).
• The Lake Oswego Tigard Partnership Water Treatment Plant(WTP)is the only source online.
• Two storage assumptions were modeled:
» Scenario A: Reservoirs 1-1, 1-2, 2,4, 9-1,and 9-2 are offline.
» Scenario B:Only Reservoirs 9-1 and 9-2 offline.
• No new storage reservoir is online.
Figure 5 shows the proposed pipeline network for the 2030 planning year and the model predicted
maximum pressures at each junction in Kingston Terrace under 2030 ADD condition for storage
scenario B. Note,the modeled pressure results were similar for storage scenario A and fall in the same
pressure categories as shown in Figure 5, so only one results figure is included.
As shown in Figure 5,the model predicts that all junctions in Kingston Terrace will have pressures above
80 psi under 2030 ADD conditions meaning that all service connections will require individual PRVs to be
compliant with Oregon Plumbing Specialty Code.
CITY OF TIGARD
KINGSTON TERRACE WATER SYSTEM PLAN ADDENDUM 13
ADDENDUM TO 2020 WATER SYSTEM PLAN
JULY 2024/FINAL/CMMOLLO
1
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Figwe 5 Neremum Pressures under 203D ADD Coedtms —
cry OF TIGARD
TIGARD KINGSTON TERRACE WATER MASTER RLAN ADYENLUM
ADDENDUM TO 2020 WATER SYSTEM PLAN
JULY 2024/FINAL/CAROLLO
5.3.2 Kingston Terrace 2040 PHD
The Kingston Terrace 2040 PHD model scenario was used to review minimum pressures and maximum
velocities under 2040 PHD conditions with the following assumptions:
■ Kingston Terrace Phases 1-5 online with 643 gpm in water demands allocated (the existing diurnal
pattern was assigned to the model junctions).
■ The WTP,ASR 1,ASR 2,ASR 3 and Well 2 are online.
■ Two storage assumptions were modeled:
» Scenario A: Reservoirs 1-1, 1-2, 2,4,9-1,and 9-2 are offline with a new Reservoir 19 (located near
the intersection of SW 150th Avenue and SW Woodhue Street)online with a capacity of
approximately 1.5 MG.
• Note,additional storage was needed to stabilize the HGL in the 410 PZ under 2040 PHD
conditions for storage scenario A so Reservoir 19, as modeled for the 2020 WSP,was
activated and the volume was adjusted.
• Scenario B:Only Reservoirs 9-1 and 9-2 offline.
Figure 6 shows the proposed pipeline network for the 2040 planning year and the model predicted
minimum pressures at each junction in Kingston Terrace under 2040 PHD conditions for storage scenario
B. Note,the modeled pressure results were slightly higher for storage scenario A,so only results for
storage scenario B are included as the more conservative results.
As shown in Figure 6,the model results show that no junction pressures are below 30 psi under the stated
conditions.
The model results show that no pipelines in Kingston Terrace have velocities that exceed 3 fps under
2040 PHD conditions.
CITY OF TIGARD
KINGSTON TERRACE WATER SYSTEM PLAN ADDENDUM 15
ADDENDUM TO 2020 WATER SYSTEM PLAN
JULY 2020/FINAL/GUOLLO
9�
A
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Figure 6 NLngsbn Terrace-Kamm Pressures under 2040 PHD Conel ons
ITO OF TIGARD
TIGARD KINGSTON TERRACE WATER MASTER.LAN AOYENLS2M
ADDENDUM TO 2020 WATER SYSTEM PLAN
JULY 2024/FINAL/CAROLLO
5.3.3 Kingston Terrace 2040 MDD + FF
The Kingston Terrace 2040 MDD + FF model scenario was used to review residual pressures under
2040 MDD + FF conditions with the following assumptions:
• Kingston Terrace Phases 1-5 are online with 643 gpm in water demands allocated set to run as steady
state(no diurnal pattern).
• FF requirements, based on land use,as shown in Figure 7.
• The WTP,ASR 1,ASR 2,ASR 3, and Well 2 are online.
• Two storage assumptions were modeled:
» Scenario A:Reservoirs 1-1, 1-2, 2,4,9-1,and 9-2 are offline with a new Reservoir 19 (located near
the intersection of SW 150th Avenue and SW Woodhue Street)online with a capacity of
approximately 1.5 MG.
» Scenario B:Only Reservoirs 9-1 and 9-2 offline.
Figure 8 shows the model predicted residual pressures at each junction based on the assigned FF
requirements under 2040 MDD plus FF conditions for storage scenario B. Note,the modeled pressure
results were slightly higher for storage scenario A,so only results for storage scenario B are included as
the more conservative results.
As shown in Figure 8,the model predicts that there are no residual pressures below 20 psi under
2040 MDD + FF conditions.
CITY OF TIGARD
KINGSTON TERRACE WATER SYSTEM PLAN ADDENDUM 17
ADDENDUM TO 2020 WATER SYSTEM PLAN
JULY 2024/FINAL/CAROLED
1
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Fiqule 7 amoeba Terrace-2000 FKe Flow Reowremerns
CITY OF TIUARO
TIGARD KINGSTON TERRACE WATER MASTER RLAN ADDENDUM
ADDENDUM TO 2020 WATER SYSTEM PLAN
IULY 202.1/FINAL/CAIOLLO
i I
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Figure 8 Residual Pressures larder 2400 MDC+FF Cord,bons
CITY OF TIGARD
TIGARD KINGSTON TERRACE WATER MASTER+LAN ADDENDUM
ADDENDUM TO 2020 WATER SYSTEM PLAN
JULY 2024/FINAL/CAROLLO
5.3.4 Kingston Terrace Buildout PHD
The Kingston Terrace Buildout PHD model scenario was used to review minimum pressures and maximum
velocities under buildout PHD conditions for Kingston Terrace(2040 PHD conditions for the rest of the
system)with the following assumptions:
• All Kingston Terrace Phases are online with 1,525 gpm in water demands allocated (the existing
diurnal pattern was assigned to the model junctions).
• The WTP,ASR 1,ASR 2,ASR 3,and Well 2 are online.
• Two storage assumptions were modeled:
» Scenario A: Reservoirs 1-1, 1-2,2,4, 9-1,and 9-2 are offline with a new Reservoir 19 (located near
the intersection of SW 150th Avenue and SW Woodhue Street)online with a capacity of
approximately 1.5 MG.
• Similar to the Kingston Terrace 2040 PHD storage scenario A,additional storage was needed
to stabilize the HGL in the 410 PZ under 2040 PHD conditions for storage scenario A so
Reservoir 19 was activated,and the volume was adjusted.
X. Scenario B:Only Reservoirs 9-1 and 9-2 offline.
Figure 9 shows the proposed pipeline network for Kingston Terrace buildout and the model predicted
minimum pressures at each junction in Kingston Terrace under buildout PHD conditions for storage
scenario B. Note,the modeled pressure results were slightly higher for storage scenario A, so only results
for storage scenario B are included as the more conservative results.
As shown in Figure 9,the model results show that no junction pressures are below 30 psi under the stated
conditions.
The model results show that no pipelines in Kingston Terrace have velocities that exceed 3 fps under
buildout PHD conditions.
CITY OF TIGARD
KINGSTON TERRACE WATER SYSTEM PLAN ADDENDUM 20
ADDENDUM TO 1020 WATER SYSTEM PLAN
JULV 2024/FINAL/CAtOLLO
Figure 9 Nurgsbn Terrace-Mlmmun Pressures under Butldwt PHD Conditions
CITY OF TIGARD
TIGARD KINGSTON TERRACE WATER MASTER PLAN ADDENDUM
ADDENDUM TO 2020 WATER SYSTEM PLAN
JULY 2024/FINAL/CAROLLO
5.3.5 Kingston Terrace Buildout MDD + FF
The Kingston Terrace Buildout MDD + FF model scenario was used to review residual pressures under
buildout MDD+ FF conditions for Kingston Terrace(2040 MDD conditions for the rest of the system)with
the following assumptions:
• All Kingston Terrace phases online with 1,525 gpm in water demands allocated set to run as steady
state(no diurnal pattern).
• FF requirements, based on land use,as shown in Figure 10.
• The WTP,ASR 1,ASR 2,ASR 3,and Well 2 are online.
• Reservoirs 1-1, 1-2,2,4,9-1, and 9-2 are offline.
• Two storage assumptions were modeled:
» Scenario A: Reservoirs 1-1, 1-2,2,4,9-1,and 9-2 are offline with a new Reservoir 19 (located near
the intersection of SW 150th Avenue and SW Woodhue Street) online with a capacity of
approximately 1.5 MG.
• Scenario B:Only Reservoirs 9-1 and 9-2 offline.
Figure 11 shows the model predicted residual pressures at each junction based on the assigned FF
requirements under Buildout MDD plus FF conditions for storage scenario B. Note,the modeled pressure
results were slightly higher for storage scenario A,so only results for storage scenario B are included as
the more conservative results.
As shown in Figure 11,the model predicts that there are no residual pressures below 20 psi under
buildout MDD + FF conditions.
CITY OF TIGARD
KINGSTON TERRACE WATER SYSTEM PLAN ADDENDUM 22
ADDENDUM TO 2020 WATER SYSTEM PLAN
)ULY 2024/FINAL/CAMOLLO
x
lure 10 Kingston Terms-Raided Fire Floe Requirements
CITY OF TIGARO
TIGARD KINGSTON TERRACE WATER MASTER RLAN ADDENDUM
ADDENDUM TO 2020 WATER SYSTEM PLAN
JULY 2024/FINAL/CAROLLO
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Figure 11 Kingston Tema-Readied Presume under 8uddoul WO+FF CondRoes
CITY OF TISARD
TIGARD If INGSTON TERRACE WATER MATTER.LAN ADDENIYIM
ADDENDUM TO 2020 WATER SYSTEM PLAN
JULY 2024/FINAL/CAROLLO
5.3.6 Hydraulic Model Analysis Conclusions
The results of the hydraulic model analysis can be summarized as follows:
• The model predicts that pressures are generally higher than 80 psi in Kingston Terrace due to the low
customer elevations relative to the HGL of the pressure zone. Individual PRVs will be required for
compliance with the Oregon Plumbing Specialty Code.
• The model results show that the proposed 16-inch-diameter pipeline on SW Beef Bend Road is
sufficient to meet pressure and velocity requirements, but a second connection from the north is
recommended to provide redundancy to Kingston Terrace, specifically to the Town Center before
additional areas are developed.
• The model results show that a 12-inch-diameter pipe loop through the Town Center is sufficient to
serve commercial and municipal buildings in the area.
• The model results shows that an 8-inch-diameter pipe loop to serve Phases 7 and 8 south of the
proposed Town Center is sufficient to meet pressure and velocity requirements. If any high-density
residential,commercial, or municipal buildings (with FF requirements above 1,500 gpm)are planned
for this area,a 12-inch-diameter pipe loop may be required.
• The model results show that 8-inch-diameter pipe looping is sufficient to meet pressure and velocity
requirements in the Beef Bend,Central, and Rural character neighborhoods(Phases 5-6 and 9-12). If
any high-density residential,commercial,or municipal buildings (with FF requirements above 1,500
gpm) are planned for the southern part of these neighborhoods,a 12-inch-diameter pipe loop may
be required.
• During PHD,the model required additional storage in the 410 PZ to maintain HGL:
» Approximately 1.5 MG for 2040 demands.
» Approximately 2.0 MG for Kingston Terrace Buildout demands.
SECTION 6 RECOMMENDED IMPROVEMENTS
This section summarizes the improvements needed to meet storage, pumping, pressure, and velocity
criteria in Kingston Terrace.
6.1 Storage
If Reservoir 2 is taken offline in 2025 and Reservoirs 1-1, 1-2,and 4 are taken offline in 2027(storage
scenario A), new storage is needed in 2027 to offset the storage taken offline. By Kingston Terrace
buildout,approximately 8.1 MG of usable storage is needed to meet storage requirements in the 410 PZ.
Approximately 2.0 MG of the volume is needed to serve Kingston Terrace,and the remaining volume
(6.1 MG)is needed to meet growth in the rest of the 410 PZ and to offset the volume lost when 2.96 MG
of storage is taken offline.
CITY OF TIGARD
KINGSTON TERRACE WATER SYSTEM PLAN ADDENDUM 25
ADDENDUM TO 2020 WATER SYSTEM PLAN
JULY 2024/FINAL/CAROLLO
If Reservoirs 2, 1-1, 1-2, and 4 remain online(storage scenario B),new storage is needed by 2029. By
Kingston Terrace buildout,approximately 6.1 MG of usable storage is needed to meet storage
requirements in the 410 PZ.Approximately 2.0 MG of the volume is needed to serve Kingston Terrace,and
the remaining volume(4.1 MG)is needed to meet growth in the rest of the 410 PZ.
6.2 Supply and Pumping
With the assumed timing of the development of Kingston Terrace, additional supply capacity is needed by
2030 to meet the total system firm supply capacity.To meet system supply requirements by the
Kingston Terrace buildout,approximately 6.1 mgd of additional supply capacity is needed to meet a total
system MDD of approximately 24 mgd.Of the 6.1 mgd additional required supply capacity,2.2 mgd is
needed to serve Kingston Terrace based on the demand projections.
With the assumed timing of the development of Kingston Terrace, additional pumping is needed by 2041
to meet the total system pumping requirements.To meet pumping requirements in the 410 PZ by the
Kingston Terrace buildout,approximately 3.2 mgd of additional pumping capacity to the 410 PZ is
needed, 2.2 mgd of which would be needed to serve Kingston Terrace.
The City's 2020 WSP outlines two new supply projects:S-1 LOT Supply Expansion and ASR 4. For project
S-1, system improvements are needed to expand LOT supply from 14 mgd to 18 mgd,including a 50
percent cost share with Lake Oswego for adding a finished water pump at the LOT WTP, installation of
approximately 5,600 LF of 36-inch-diameter pipeline from the Waluga Reservoir to SW Bangy Road,
addition of a sixth pump at PS 5, and installation of approximately 250 LF of 24-inch-diameter pipeline
across Fanno Creek
Based on the existing supply,demand projections, and S-1,the capacity of ASR 4 would need to be
approximately 2.1 mgd.
6.3 Pipeline Network
Figure 12 shows the recommended transmission pipeline network to serve Kingston Terrace at buildout
based on the hydraulic model results.Figure 12 includes the recommended 18-inch-diameter second
connection to Kingston Terrace from the south end of the existing 18-inch-diameter pipeline on SW River
Terrace Boulevard.
The total length of pipe,by diameter for pipeline shown in Figure 12 larger than 12-inch diameter is
summarized in Table 15.
Table 15 Summary of Pipeline Network to serve Kingston Terrace
Diameter(inches) Length(feet) Location
16 2,350 SW Beef Bend Road from SW 105th Avenue to SW Taylor Lane
18 2,000 From SW Beef Bend Road north to existing 18-inch-diameter pipeline on SW River
£Terrace Boulevard
CITY OF TIGARD
KINGSTON TERRACE WATER SYSTEM PLAN ADDENDUM 26
ADDENDUM TO 2020 WATER SYSTEM PLAN
JULY 2024/FINAL/CA1O1.1.O
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Flqure 12 Recommended(Subset Transmiswn PoeEme Network
CITY OF TIGARD
TIGARD KINGSTON TERRACE WATER MASTER RLAN ADFENDX/M
ADDENDUM TO 2020 WATER SYSTEM PLAN
JULY 2024/FINAL/CAROLLO
SECTION 7 COST ESTIMATES
Cost estimates were developed for improvements to serve Kingston Terrace based on the cost estimates
from the 2020 WSP and ASR 3 costs from 2022. The cost estimates presented in this section are in 2023
dollars.The Handy-Whitman Index(H-W Index) of Public Utility Construction Costs for the Pacific Region
for water utility construction was used to escalate costs from the 2020 WSP and the 2022 ASR 3 costs to
2023 dollars, as summarized in Table 16.
As stated in the 2020 WSP,Cost estimates represent opinions of cost only, acknowledging that final costs
of individual projects will vary depending on actual labor and material costs,market conditions for
construction, regulatory factors, final project scope,project schedule,and other factors.The Association
for the Advancement of Cost Engineering International classifies cost estimates depending on project
definition,end usage, and other factors.The cost estimates presented here are considered Class 4 with an
end use being a study or feasibility evaluation and an expected accuracy range of-30 percent to
+50 percent.As the project is better defined, the accuracy level of the estimates can be narrowed.
Total project costs from the 2020 WSP included the following indirect costs and contingencies:
• Construction contingency:30 percent.
• Oregon Corporate Activity Tax:1 percent.
• Engineering allowance:20 percent.
• Permitting, inspections, and administration: 5 percent.
• City project management: 15 percent.
The cost estimates in this addendum include all indirect costs and contingencies outlined above.
All construction cost estimates from the 2020 WSP included the following assumptions:
• No property acquisition cost included.
• No easement or right-of-way cost included.
• Costs include arterial roadway resurfacing cost and does not include sidewalk or half- or full-street
replacement cost
Table 16 H-W Indices of Water Utility Construction in the Pacific Region
January 2020 Index January 2022 Index January 2023 Index
Average for Water Utility Construction 932 1136 1270
Electrical Pumping Equipment 1374 1593 1801
Mains-Averall Al Types 842 1003 1119
7.1 Storage Cost Estimates
The construction cost estimate for project R-2(Reservoir 19)from the 2020 WSP included the following:
• Reservoir structure and appurtenances(AWWA D110 Prestressed circular concrete reservoir).
• Reservoir foundation and excavation.
CITY OF TIGARD
KINGSTON TERRACE WATER SYSTEM PLAN ADDENDUM 28
ADDENDUM TO 2020 WATER SYSTEM PLAN
JULY 2024/FINAL/CAROLLO
• Yard piping.
• Site work and landscaping.
• Electrical and instrumentation and controls.
• 2,000 linear feet (LF)of 16-inch-diameter pipe.
• 2,000 LF of surface replacement.
• Mobilization, bonds,insurance, shop drawings.
The construction cost estimate was adjusted using the"average for water utility construction" H-W Indices
from Table 16 and then scaled to match the proposed storage volumes in Table 10.
Table 17 summarizes the total construction cost estimate(including the 30 percent construction
contingency)and the total project cost estimate(including all other indirect costs)for each storage
scenario based on the 2020 WSP cost estimates.The total project cost estimate also includes$3.2M as an
assumption for land acquisition for all reservoir sizes,which equals the estimate for land acquisition for
Reservoir 19 in the City's CIP.
Table 17 Storage Project Cost Estimates
Scenario Description Storage Total Construction Total Project
Capacity'' Cost Estimate Cost Estimate
Scenario A Reservoir 2 offline in 2025;Reservoirs 1-1,1-2,and 4 8.0 MG $19,400,000 $30,700,000
offline in 2027
Scenario B All reservoirs remain online through 2050 6.0 MG $14,600,000 $23,800,000
—
Notes:
(1) Storage capacity was rounded to the nearest 0.5 MG.
To serve Kingston Terrace for either storage scenario, approximately 2.0 MG of storage is needed in the
410 PZ,which equates to approximately$7.0 million based on the cost estimates provided in Table 17.
This estimate does not include the cost for land acquisition.
7.2 Supply and Pumping Cost Estimates
CIP Project S-1 from the 2020 WSP is comprised of the following items:
• 5,600 LF of 36-inch-diameter pipe.
• 5,6000 LF of surface replacement for 36-inch pipe.
• 200 LF of 24-inch high-density polyethylene Pipe-auger drilling.
• 200 LF of carrier pipe and fittings.
• 50 LF of 24-inch-diameter pipe replacement.
• 50 LF of surface replacement.
• 250 horse-power pump.
• Pump Station site improvements.
• Mobilization, bonds,insurance, shop drawings.
The construction cost estimates for CIP Project S-1 LOT Supply Expansion from the 2020 WSP were
escalated using the"Electrical Pumping Equipment"and "Mains-Average All Types" H-W Indices outlined
CITY OF TIGARD
KINGSTON TERRACE WATER SYSTEM PLAN ADDENDUM 29
ADDENDUM TO 2020 WATER SYSTEM PLAN
JULY 2024/FINAL/CAROLLO
in Table 16.The total construction cost estimate(including the 30 percent construction contingency) and
the total project cost estimate(including all other indirect costs and the LOT WTP pump cost share)for
CIP Project S-1 is as follows:
• Total construction cost estimate: $4,400,000.
• Total project cost estimate: $6,900,000.
The project cost for ASR 3 includes following items:
• Mobilization, bonds,permitting, insurance;traffic control;erosion control and permitting;and
construction survey.
• The ASR 3 facility.
• Asphalt concrete paving.
• Connections to existing pipe and existing structures.
• Driller.
• Engineering.
• Special inspections.
The total cost for ASR 3 in 2022 dollars were escalated using the"Average for Water Utility Construction"
outlined in Table 16.The total project cost estimate for ASR 4 was assumed to be$7,700,000.
7.2.1 Pipeline Cost Estimates
The pipeline construction cost estimates from the 2020 WSP were escalated using the"Mains-Averall All
Types"H-W Indices from Table 16.
Costs estimates from the 2020 WSP did not include an 18-inch-diameter pipeline, so the unit costs were
scaled up to develop a cost for the 18-inch-diameter pipeline.Table 18 summarizes the total construction
cost estimate(including the 30 percent construction contingency)and the total project cost estimate
(including all other indirect costs)for the recommended transmission network for Kingston Terrace, as
shown in Figure 12,for the pipeline larger than 12-inch diameter based on the 2020 WSP cost estimates.
Table 18 Pipeline Cost Estimates
Diameter Length Total Construction Cost Estimate Total Project Cost Estimate
(inches) (feet)
16 2,350 $900,000 $1,300,030
18 ;2,000 $800,000 $1,200,000
Total 4,350 $1,700,000 $2,500,000
7.2.2 Total Cost Estimates
Table 19 summarizes the total construction costs and total project costs for all recommended
improvements.The storage cost included assumes the City takes Reservoirs 1-1, 1-2, 2, and 4 offline as
planned (storage scenario A).
CITY OF TIGARD
KINGSTON TERRACE WATER SYSTEM PLAN ADDENDUM 30
ADDENDUM TO 2020 WATER SYSTEM PLAN
JULY 2024/FINAL/CAROLLO
Table 19 Total Cost Estimates
Total Construction Cost Total Project Cost Estimate Total Project Cost Directly
Estimate Attributed to the Kingston
Terrace Development
Sbrage COO) $19,400,000 $30,700,000 $7,000,O009/
S-1 $4,400,000 $6,900,000 $3,450,000 to$7,700,000(3)
ASR 4 — $7,700,000(2
Pipeline Cost $1,700,000 $2,500,000 $2,500,000
Total Cost $25,500,0000) $47,800,000 $12,950,000 to$17,200,000
Notes:
(1) Storage cost is for storage scenario A(8.0 MG reservoir).
(2) Cost does not include land acquisition.
(3) The supply and pumping cost attributed to the Kingston Terrace Development is half of the total cost of S-1,or 2 mgd of the
4 mgd supply expansion,or the total cost of ASR 4.Cost for new supply will depend on which project is completed first S-1
or ASR 4.
(4) The total construction cost estimate does not include a total construction cost estimate for ASR 4.
CITY OF TIGARD
KINGSTON TERRACE WATER SYSTEM PLAN ADDENDUM 31
ADDENDUM TO 2020 WATER SYSTEM PLAN
JULY 2024/FINAL/CAROLLO
APPENDIXA SUPPORTING DOCUMENTS FROM
KING CITY AND CONSULTANT
CITY OF TIGARD
KINGSTON TERRACE WATER SYSTEM PLAN ADDENDUM
SITE PLAN AND PHASING PLAN FOR KINGSTON
TERRACE TOWN CENTER
Kingston Terrace Town Center Phasing Plan
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WATER CONCEPT PLAN FOR KINGSTON TERRACE
TOWN CENTER
Kingston Terrace Town Center. WATER CONCEPT PLAN
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FUTURE STREETS PLAN
FIGURE 25: STREET FUNCTIONAL CLASSIFICATIONS
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Note: Routes west of 137th under supplemental review as part of the Kingston Terrace Master Plan.
CITY OF KING CITY • TRANSPORTATION SYSTEM PLAN • MARCH 2023 - REVIEW DRAFT
EXHIBIT B
RECOMMENDATIONS AND FINDINGS OF
THE PLANNING COMMISSION N19
FOR THE CITY OF TIGARD, OREGON TIGARD
SECTION I. APPLICATION SUMMARY
CASE NAME: WATER SYSTEM PLAN ADDENDUM — KINGSTON TERRACE
CASE NO.: Comprehensive Plan Amendment (CPA) CPA2026-0001
PROPOSAL: The City of Tigard proposes to amend the Tigard Water System Plan, an
ancillary document to the Tigard Comprehensive Plan, in order to incorporate
the area of Kingston Terrace in King City. The City of Tigard is King City's water
provider.
The proposed addendum to the Water System Plan is included in
Attachment 1 and summarized below in Section III of this report.
APPLICANT: City of Tigard
13125 SW Hall Blvd.
Tigard, OR 97223
LOCATION: Citywide
APPLICABLE Statewide Planning Goals 1 (Citizen Involvement), 2 (Land Use Planning),
REVIEW 10 (Housing), 11 (Public Facilities and Services); Metro Urban Growth
CRITERIA: Management Functional Plan Title 8; Tigard Comprehensive Plan Policies
1.1.2, 2.1.1, 2.1.2, 2.1.3, 11.2.2, 11.2.8; and Tigard Community Development
Code Chapters (TDCD): 18.710 and 18.790.
SECTION II. PLANNING COMMISSION RECOMMENDATION
The Planning Commission unanimously recommends that the City Council adopt amendments to the
Tigard Water System Plan with any alterations determined through the public hearing process.
SECTION III. BACKGROUND INFORMATION AND PROJECT SUMMARY
In 2020,the City of Tigard updated its Water System Plan (WSP).The WSP is a comprehensive study
of the city's drinking water system, addressing water supply capacity needs and guiding water
system infrastructure improvements in the Tigard Water Service Area. The WSP is scheduled to be
WATER SYSTEM PLAN ADDENDUM-KINGSTON TERRACE CPA2026-0001
4/20/2026 PUBLIC HEARING,STAFF REPORT TO THE PLANNING COMMISSION PAGE 1 OF 7
updated again in Fiscal Year 2027. Major changes to the Tigard water system in between Water
System Plan updates are addressed as addendums. In March 2024, King City annexed Urban
Reserve Area (URA) 6D through its adoption of the Kingston Terrace Master Plan. This area of
western King City is known as Kingston Terrace.
Per the 2014 intergovernmental agreement between Tigard and King City, Tigard is obligated to
supply water to King City, including areas annexed into the King City city limits. The 2020 WSP did
account for future water supply requirements in URA 6D using assumed housing development
densities. However, it did not address how water service would be delivered to the area.
Additionally, the housing development densities in the Kingston Terrace Master Plan are different
than those assumed in the 2020 WSP. The attached Kingston Terrace Addendum to the 2020
WSP (KT Addendum) addresses those issues.
The KT Addendum found that Tigard can serve the Kingston Terrace area by expanding the 410-
foot pressure zone. The city's current water supply and storage infrastructure are sufficient to meet
the initial water demands of Kingston Terrace. However, supply and storage improvements are
needed in order to supply water to the Kingston Terrace area at its expected full buildout, which
are summarized in Section 6 of the KT Addendum. Cost summaries of these improvements are
included in Section 7 of the KT Addendum. Because the 2020 WSP included preliminary
assumptions for serving Kingston Terrace, the required capital improvement projects related to
storage and supply are already included in the Capital Improvement Plan.
The Water Advisory Board (WAB) was briefed on the Kingston Terrace WSP Addendum at the
1/8/2026 WAB meeting. At the 2/11/2026 WAB meeting, the WAB approved a motion
recommending the City Council to adopt the KT Addendum to the 2020 WSP.
The findings below support the adoption of the proposed Comprehensive Plan amendments, as
attached to this staff report and provided in the main Downtown Tigard Land Use and
Transportation Recommendations Report.
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 Comprehensive
Plan amendments have a limited scope, 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.
WATER SYSTEM PLAN ADDENDUM-KINGSTON TERRACE CPA2026-0001
4/20/2026 PUBLIC HEARING,STAFF REPORT TO THE PLANNING COMMISSION PAGE 2 OF 7
FINDING: The Water Advisory Board (WAB) was briefed on the Kingston Terrace WSP Addendum
at the January 8, 2026 WAB meeting. At the February 11, 2026 WAB meeting, the WAB approved a
motion recommending the City Council to adopt the KT Addendum to the 2020 WSP.
Notice was provided of the hearings to adopt this addendum to the Water System Plan. Notice
requirements are set forth in Section 18.710.110 (Legislative Procedure) of the Tigard Community
Development Code. Project information and documents were published to the city website prior to
the public hearings. A minimum of two public hearings will be held (one before the Planning
Commission and the second before the City Council). These hearings present an opportunity for
public testimony. 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. Changes to the
city's Comprehensive Plan must also be consistent with the statewide planning goals. The process
for review of Comprehensive Plan changes is the Post-Acknowledgment Plan Amendment (PAPA).
The city submitted the draft Comprehensive Plan amendments and the Land Use and
Transportation Recommendations Report to DLCD for review through the PAPA process. No
comments were received to date. This goal is satisfied.
Statewide Planning Goal 10 — Housing:
This goal requires cities and counties to provide adequate capacity for needed housing. OAR
Chapter 660 Division 8, which implements Goal 10, states that "the purpose of the division is
to ensure opportunity for the provision of adequate numbers of needed housing units, the
efficient use of buildable land within urban growth boundaries, and to provide greater
certainty in the development process so as to reduce housing costs."
FINDING: The purpose of this update to the Water System Plan is to facilitate the development of
the Kingston Terrace area of King City. This area was added to the Metro Urban Growth Boundary
in 2018, following a Concept Planning process. The Comprehensive Planning of this area was
completed in July 2023, with an adopted Kingston Terrace Master Plan. This plan was built on a
project growth of 3,300 to 3,600 new units of housing.
By providing water service to this area in an orderly manner, the City of Tigard is supporting the
development of new units to address the ongoing regional housing shortage. This goal is
satisfied.
Statewide Planning Goal 11 — Public Facilities and Services:
This goal outlines the requirements for public facilities plans to regulate facilities and services
across Oregon. Public facilities plans must determine:
WATER SYSTEM PLAN ADDENDUM-KINGSTON TERRACE CPA2026-0001
4/20/2026 PUBLIC HEARING,STAFF REPORT TO THE PLANNING COMMISSION PAGE 3 OF 7
• The existing conditions of each public facility,
• What future additional needs exist for that public facility,
• The costs of these needs, and
• What revenue sources the city may have available to pay those costs.
The current Water System Plan meets each of these requirements. The proposed addendum to
incorporate the Kingston Terrace area of King City augments this plan to identify where future
additional needs exist for the water system, the costs of those needs, and the revenue sources
available to pay those costs, including system development charges and water user fees.
CONCLUSION: Based on the findings above and the related findings below, the Planning
Commission finds the proposed map and text amendments are consistent with
applicable Statewide Planning Goals.
METRO'S URBAN GROWTH MANAGEMENT FUNCTIONAL PLAN
State planning regulations require cities within the Metro service area to adopt and amend
Comprehensive Plans in compliance with Metro's Urban Growth Management Functional Plan.
Because the proposed Code Amendments have a limited scope and the text amendments address
only some of the topics in Metro's Urban Growth Management Functional Plan, only applicable
Titles are addressed below.
Title 8—Compliance Procedures
Title 8 requires that the city's Comprehensive Plan and plan amendments be consistent with
the Urban Growth Management Functional Plan. It also requires that Metro be notified in
advance of subsequent amendments to the city's Comprehensive Plan.
FINDING: The Comprehensive Plan has been previously acknowledged by Metro to be in
compliance with Title 8. The only portion of the Comprehensive Plan being amended is the Water
System Plan, which is an ancillary document to the Comprehensive Plan. Notice of these proposed
amendments have been provided to Metro in accordance with the requirements of Title 8 of the
Urban Growth Management Functional Plan.
CONCLUSION: Based on the findings above,the Planning Commission finds that the proposed
map and amendments are consistent with the applicable provisions of Metro's
Urban Growth Management Functional Plan.
TIGARD COMPREHENSIVE PLAN
State planning regulations require cities to adopt and amend their comprehensive plans in
compliance with the state land use goals and consistent with their adopted comprehensive plan
goals and policies. The Tigard Comprehensive Plan therefore implements the Statewide Planning
Goals,therefore the above findings of compliance with applicable statewide planning goals support
the findings of compliance with the Comprehensive Plan.
WATER SYSTEM PLAN ADDENDUM-KINGSTON TERRACE CPA2026-0001
4/20/2026 PUBLIC HEARING,STAFF REPORT TO THE PLANNING COMMISSION PAGE 4 OF 7
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: The Water Advisory Board (WAB) was briefed on the Kingston Terrace WSP Addendum
at the January 8, 2026 WAB meeting. At the February 11, 2026 WAB meeting, the WAB approved a
motion recommending the City Council to adopt the KT Addendum to the 2020 WSP.
Notice was provided of the hearings to adopt this addendum to the Water System Plan. Notice
requirements are set forth in Section 18.710.110 (Legislative Procedure) of the Tigard Community
Development Code. Project information and documents were published to the city website prior to
the public hearings. A minimum of two public hearings will be held (one before the Planning
Commission and the second before the City Council). These hearings present an opportunity for
public testimony. This policy is satisfied.
Comprehensive Plan Goal 2: Land Use Planning
Policy 2.1.1: The City's land use program shall establish a clear policy direction, comply with
state and regional requirements, and serve its citizens' own interests.
FINDING: The proposed amendments to the Water System Plan comply with all state and regional
requirements, as the previous findings indicate. The proposed addendum also establishes clear
policy direction for the deployment of and funding of water system infrastructure. This policy is
satisfied.
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 through the findings and conclusions of this staff report, the proposed
amendments 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: This addendum was coordinated with King City. Copies of the proposed addendum to
the Water System Plan were sent to affected agencies and each agency was invited to comment on
the proposal. Any comments submitted by affected agencies have been incorporated into the
proposed addendum. This policy is satisfied.
Policy 11.2.2: The City shall develop and maintain a water system master plan to coordinate
the improvement and expansion of Tigard Water Service Area infrastructure to serve current
and projected demand.
WATER SYSTEM PLAN ADDENDUM-KINGSTON TERRACE CPA2026-0001
4/20/2026 PUBLIC HEARING,STAFF REPORT TO THE PLANNING COMMISSION PAGE 5 OF 7
FINDING: The proposed addendum to the Water System Plan coordinates the improvement and
expansion of the Tigard Water Service Area infrastructure to serve current and project demand in
Kingston Terrace and King City. This policy is satisfied.
Policy 1.2.8: The City shall require all new development needing a water supply to:
A. connect to a public water system;
B. pay a system development charge and other costs associated with extending service;
C. ensure adequate pressure and volume to meet consumption and fire protection
needs; and
D. extend adequately sized water lines with sufficient pressure to the boundaries of
the property for anticipated future extension.
FINDING: Kingston Terrace residents will be required to connect to the public water system through
the application of the Oregon Residential Specialty Code and King City's development code. Those
users will pay a system development charge in accordance with the intergovernmental agreement
between the two cities. This addendum ensures that there will be adequate pressure and volume
as well as adequately sized water lines to meet consumption and fire protection needs as shown in
the analysis in the documents. This policy is satisfied.
CONCLUSION: Based on the findings above, the Planning Commission concludes that the
proposed comprehensive plan amendments are consistent with applicable
provisions of the Tigard Comprehensive Plan.
APPLICABLE PROVISIONS OF THE TIGARD DEVELOPMENT CODE
Section 18.790: Zoning Map and Text Amendments
18.790.020 Legislative Amendments
Legislative amendments are processed through a Legislative procedure, as provided in
Section 18.710.110.
FINDING: The proposed amendments are legislative in nature. Therefore, the amendments will be
reviewed under the Legislative Procedure as set forth in the chapter. This standard is met.
Section 18.710: Decision Making Procedures
18.710.110 Type IV Procedure
Notice of hearing.
1.All Legislative applications require two hearings, one before the Planning Commission and
one before the City Council.
FINDING: This procedure requires public hearings by both the Planning Commission and City
Council. These public hearings will be conducted on April 20, 2026, and May 26, 2026 respectively.
WATER SYSTEM PLAN ADDENDUM-KINGSTON TERRACE CPA2026-0001
4/20/2026 PUBLIC HEARING,STAFF REPORT TO THE PLANNING COMMISSION PAGE 6 OF 7
This standard is met.
2. A notice of hearing will be provided as required by state law, and an affidavit of mailing
will be included in the record that identifies the mailing date and the names and addresses
of the mailing recipients.
FINDING: State law provides for specific noticing requirements for legislative changes. Notice must
be provided to DLCD of a proposed Post Acknowledgement Plan Amendment at least 35 days prior
to the first hearing. Notice meeting this requirement was provided to DLCD on March 3, 2026,
48 days prior to the first hearing. This standard is met.
CONCLUSION: Based on the findings above, the Planning Commission concludes that the
proposed Comprehensive Plan amendments and transportation
recommendations are consistent with applicable provisions of the Tigard
Development Code.
SUMMARY As shown in the findings above, the Planning Commission concludes that the
CONCLUSION: proposed amendments are consistent with the applicable Statewide Planning
Goals; Metro's Urban Growth Management Functional Plan; applicable Tigard
Comprehensive Plan goals and policies, and the applicable provisions of the
City's implementing ordinances.
SECTION V. AGENCY COMMENTS
TVF&R, METRO, ODOT, DLCD, CWS, TTSD, Tigard Water District, City of Beaverton, City of
King City, were notified of the proposed amendments.
SECTION VI. PUBLIC COMMENTS
No public comments have been received at the time of the staff report.
ATTACHMENTS:
Attachments:
1. Kingston Terrace Water System Plan Addendum
i--
May 4, 2026
PREPARED BY: Schuyler Warren DATE
Assistant Director of Community Development
9722 L- May 6, 2026
APPROVED BY: Nathan Jackson, President DATE
Tigard Planning Commission
WATER SYSTEM PLAN ADDENDUM-KINGSTON TERRACE CPA2026-0001
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