09/06/2000 - Packet Summer Lake Task Force
MEMO
TO: Summer Lake Task Force
RE: Upcoming Task Force Meeting DATE: August 31,2000
September 6,2000
Tigard Water Building
FROM: Vaughn Brown
The next Task Force meeting has two main purposes:
1. Review the criteria worksheet and complete a preliminary options evaluation
2. Outline the participant recruitment, involvement process and content for the upcoming
Neighborhood Meeting
As per the Task Force request,this meeting is designed to provide a more detailed review of the
options proposed and discussed at the last meeting.
Enclosed in this meeting briefing packet are the August 2 meeting summary and a Criteria
Statements final draft which includes the revisions made at the last meeting. Also included is the
technical team's draft evaluation worksheet.
We will spend the first part of the meeting discussing this worksheet and completing the rating
column for each option. Please take the time to look at the worksheet and come prepared with
questions and suggestions in order to complete the task force's preliminary options evaluation.
In the second part of the meeting we will be planning for the Neighborhood Meeting. Please
come with ideas on how to recruit the appropriate people to attend and participate. We will
outline a meeting agenda, identify what information displays we need to prepare and determine
what input you need to complete your task force responsibilities.
Thank you for your participation on this project. Looking forward to seeing you on Wednesday
the September e.
Summer Lake Task Force
September 6, 2000
6:30-9:00 PM
Tigard Water Building
Agenda
6:30 Welcome and Meeting Purpose Brian
Review Previous Meeting Minutes
6:45 Conceptual Options Review Greg
7:05 Public Comment
7:15 Alternatives Evaluation Task Force
Complete worksheet Vaughn
8:10 Public Comment
8:20 Neighborhood Meeting Plan Task Force
Date, Time, Location
Feedback Needs
Meeting Format & Materials
Task Force Role
8:55 Next Steps Vaughn
Schedule Next Meetings
9:00 Close Meeting Vaughn
Meeting Water-Temperature Standards in the Tualatin River and its tributaries
In 1996,to create year-round habitat for salmonids(trout and salmon) in virtually all of its waters,the State
of Oregon set a maximum water-temperature standard of 17.8°C (64°F) based on a 7-day moving average
of daily maximum temperatures. This means that the Tualatin River and all of its tributaries, including Fanno
Creek and its Summer Creek tributary must meet this standard.
Owing to conclusions that can be drawn from it, a 1997 U.S. Geological Survey(USGS)study report' is
relevant to the ongoing debate about the efficacy of breaching Summer Lake dam.The report shows that
the law is unenforceable in the lower reaches of the Tualatin River because such a low temperature is
unattainable by any reasonable means. Complying with law is predicated on dramatically lowering existing
water temperatures during summer—by as much as 8°F in July! The USGS study proves that doing so will
not be possible—certainly not below River Mile 10. Fanno Creek, and the waters it receives from Summer
Creek, enter the Tualatin at River Mile 9.3. These facts may come to light soon.They strongly suggest
Tualatin Riverkeepers will ultimately not win a lawsuit in which it complains the Environmental Protection
Agency has been derelict in failing to enforce quality standards in a stormwater permit issued to Unified
Sewerage Agency.The impossibility of meeting the temperature standard year-round in the lower reaches of
the Tualatin River raises doubts about the future of the law. Will the State legislature and the courts stand
behind a law that makes Fanno and Summer Creeks meet a year-round standard that cannot be met on the
Tualatin River,just 6.4 stream miles downstream from Summer Lake dam?
Reports by USGS and State authorities indicate that meeting other existing water quality standards in the
lower Tualatin River will be extremely difficult, and may be impossible. Generally,the public is unaware that
a"one-size fits all"approach to setting water quality standards cannot be reasonably sustained. Urban-
ization, slow streams and naturally high soil phosphorus in the Tualatin River basin do not lend themselves
to meeting these impossibly stringent water quality standards. It seems the public must pay dearly before it
comes to know the truth—"that a silk purse cannot be made from a sow's ear."
The following describes the processes used in the USGS study and its results. Page numbers from the
report are provided for easy reference.
Using continuous water temperature, streamflow and meteorological data gathered in 1994(a year with a
typical flow regime) USGS quantified seasonal and spatial water temperatures in the main stem of the
Tualatin River using two"dynamic-flow heat-transfer models." One model characterizes the year-round
thermally homogenous upper river and the other describes the thermally stratified (during low flows)
downstream reaches. Nine management scenarios, besides an"Existing conditions" (current flow
management practices) scenario,were modeled to evaluate stream temperatures responses under various
hypothetical stream management conditions.
The study findings concerning the lowest 10 miles of the Tualatin River are especially interesting. They
show that none of the following four regimes,and none of the 10 studied,will suffice to meet the
temperature standard:2 Improving temperatures by as much as 2°C(3.6°F)on all upstream tributaries
(Scenario 6)or by coupling that with no effluents(warm waters)from the Rock Creek or Durham water
treatment plants(Scenario 10)or by providing maximum possible riparian vegetative shading along the
main stem and upstream tributaries(Scenario 4b) or by returning the Tualatin River basin to a simulated
"natural"(pre-history)condition (Scenario 3). The modeling data show,for all these temperature-
lowering scenarios,the readings in the lowest 10 miles of the Tualatin River would exceed the 17.8°
C standard from late June into earl October--doing so 100
/
of the time during July,August ust and
September! (Pgs. 119, 125, 131 and 137)
The modeling results lead inevitably to the conclusion that significantly lowering ng temperatures in the
Summer-Fanno Creeks system can do nothing to improve fish habitat or meet the temperature standard in
the Tualatin River, even reducing, as in Scenario 6,the water temperature in the Summer-Fanno
Creeks system by 3.6°F! Yet, at a recent Summer Lake Task Force meeting it was stated that"just a little
improvement" in water quality would justify destruction of Summer Lake and that it is important only that the
1 "Relations of Tualatin River Water Temperatures to Natural and Human-Caused Factors"by John C.
Risley, U.S.Geological Survey, Water-Resources Investigations Report 97-4071,prepared in cooperation
with the Unified Sewerage Agency(USA)of Washington County,Oregon, 1997,pp. 143.
'Bold is supplied here and elsewhere in the document for easy re-reading and for emphasis.
1
Project"works toward"meeting applicable regulations. In fact,whether dam breaching or removal would
produce any actual benefit to other water quality parameters or to fish habitat in the lower parts of Summer
Creek or to Fanno Creek is very doubtful. As has already been stated in T
ask Force unless water temperatures upstream of Summer Lake can be kept below 17.8°C during clow-flow peruments by riiodsrt t
is senseless to remove or breach the dam to provide passage for salmonids.This is because urbanization
has already irretrievably compromised the environment in the upper Summer Creek watershed to the extent
that significant improvements in water quality cannot be made in that part of the watershed. It is a fact that a
dam has been in place at the same location for over 50 years. It is also a fact that Summer Lake dam acts
as a pollution reduction facility. It holds back most of the phosphorus and sediments that would otherwise
go downstream. Except during long dry periods, as water flows over the weir it is mixed with air and thereby
dissolved oxygen is added that would not be available to downstream waters if the weir were removed.
In studying the lower 38.4 miles of the Tualatin River,the USGS used a well-calibrated"CE-QUAL-
W2...dynamic model capable of simulating water flow, heat flow,and water quality" (Pg. 13). Testifying to
the robustness of the model, USGS states that"[t]he greatest mean daily difference between simulated and
observed temperatures was less than 3°C and most of the time was less than 1°C." (Pg. 24.)
"During the months from June through September,water temperatures in the lower part of the Tualatin River
(river mile[RM]38 to RM 0)typically violate the 17.8°C (64°F)criterion. The July mean of the 7-day
moving average of daily maximum water temperatures commonly is over 22°C(72°F)." (Pg. 3)
"During low-flow periods,the stream section from RM 29.7 to RM 3.4 is slow moving and resembles
a long narrow lake more than it does a river." (Pg. 19)
A scenario 3: 'Natural'conditions' "simulation was described as follows:"The purpose of this scenario
was to estimate the spatial and temporal water-temperature variations in the Tualatin River in the
absence of current regulation of the river. However, replicating completely natural conditions in the river
basin was not feasible with the calibrated models. Prior to arrival of non-Native American settlers, many of
the low-lying areas along the Tualatin River were wetlands filled with woody debris. Over the past 150
years, inhabitants of the basin have built dikes, drained fields, and deepened the river channel. The flood
plain and channel hydraulic characteristics in the calibrated models,therefore,are not an accurate
representation of the basin prior to development. The temperatures and hydrologic regime of the boundary
tributaries entering the river also have been altered by agriculture and urbanization in the upland regions.
Nonetheless, by simply'turning off man of
the current flow management practices in the river
basin,a rough estimate of natural conditions in the basin is simulated." (Pg. 27)
The simulation of'natural'conditions was based on the following assumptions:
(1) No flow augmentation from the Trask River(Barney Reservoir)to the main stem of the Tualatin River
was provided.
(2) Both Henry Hagg Lake reservoir and the low-head diversion dam at RM 3.4 were assumed not to exist.
(3)No withdrawals for irrigation or urban water supplies were made.
(4) No flow diversions from the Oswego Canal were made(RM 6.7)
(5) No effluent was released from wastewater treatment plants.
(6) Maximum possible vegetative shading along the mainstem and tributaries was assumed. (Pg. 27)
Running the"natural"conditions scenario,the results were as follows:
"[Mater temperatures averaged over the entire river reach increased by 1.4°C and 1.0°C,
respectively, in July and August compared with the existing conditions scenario. In scenario 3,there
were no cool water releases from Henry Hagg Lake reservoir... [T]emperatures in the upper stream section
(above RM 38.4)generally were maintained below the 17.8°C criterion under natural conditions. However,
temperatures in the lower stream section continually rise at most locations closer to the mouth. In the lower
section, riparian vegetation shades less of the water surface, because the river is wider and velocities are
slower than in the upper stream section. From Rood Bridge(RM 38.4)downstream,the water
temperatures were above the 17.8°C criterion for the months of July and August.The 17.8°C
criterion was surpassed downstream of RM 20 in September and from RM 10 in June." (Pg. 33)
A scenario 4"Extremes of riparian shade conditions"simulation was described as follows:
"Conditions used in this scenario were the same as the"existing conditions"scenario,except that
variations were made to the amount of vegetative shading,which changed the amount of incoming
shortwave radiation to the heat budget. Two extremes of vegetative shading were simulated: no shading
2
and maximum potential shading along the entire mainstem and parts of the tributaries. For maximum
potential shading, riparian areas for each segment were assumed to have a maximum density of
mature trees..." (Pg.29)
Running the"Extremes of riparian shade conditions"scenario,the results were as follows:
"The models showed a consistent response to shade variation. Changes in shading always caused inverse
change in water temperatures. Except in October,the difference in no shading and current shading was
pronounced. It also is interesting to observe that the increased benefit of cooling that occurs
between current-and maximum shading conditions diminishes downstream. This phenomenon is
expected because, as the river widens,the difference between current and maximum shading affects a
smaller portion of the water surface. In July and August,water temperatures averaged over the entire river
reach increase by 2.1°C when all shade is removed.When shading was maximized[scenario 4 b]there
was a 0.9 and 0.8°C decrease for July and August, respectively." (Pg. 38)
A scenario 6, "Existing Conditions with tributary temperature reduction"was described as follows: "In
this scenario,the existing conditions were used [flow augmentations from Barney Reservoir and Hagg
Lake via Scoggins Creek;withdrawals for irrigation and urban water supply; effluent releases from
wastewater treatment plants,Oswego canal diversion and a low-head dam at RM 3.41,except that the
temperature of almost all the tributary flows [including Fanno Creek]to the models was reduced by
2°C for their entire periods of record. Temperature was not reduced for Scoggins Creek flows. These
flows come directly from the reservoir and are already relatively low.
"The purpose of this scenario was to determine how far downstream in the main stem the impact of
cooler tributary inflows would persist. If cooler tributary waters resulting from increased riparian shading
in the upland basins were able to keep the main stem cooled, riparian reforestation efforts concentrated in
the upland basins, rather than along the main stem,would be a reasonable management strategy.
Otherwise, reforestation efforts to cool the Tualatin River would be necessary in both the upland basins and
along the main stem." (Pg. 29)
Running the"Existing Conditions with tributary temperature reduction"scenario,the results were as
follows:
"A 2°C temperature reduction in the tributaries considerably lowered water temperatures in the main stem
above Rood Bridge(RM 38.4). However,the impact is less pronounced in the lower stream section (below
RM 38.4), because the ratio of tributary flow to main-stem flow is much lower in the lower stream section
than in the upper stream section. Water temperatures still exceed 17.8°C for the months of June,July,
August,and September, but exceedences occur at locations farther downstream than in scenario 1
(Existing conditions). Between RM 10 and the dam at RM 3.4,the water temperatures were almost as
high as they were in scenario 1,existing conditions. Water temperatures averaged over the entire
river reach for July and August decrease 1.1 and 0.0°C, respectively, relative to those under existing
conditions, scenario 1." (Pg.38)
"Current operations of the wastewater treatment plants increases the water temperatures for reaches
downstream of the plants under low-flow conditions. However,with or without the operation of the
wastewater treatment plants,water temperatures can still exceed the 17.8°C criterion during the
months of July,August,and September." (Pg. 53)
"None of the management scenarios showed an effective approach for lowering temperatures in the
lower river section(below RM 20)." (Pg. 53)
heb 9/2/00
3
Summer Lake Task Force Rating Scale (RS) A: Acceptable U: Unacceptable
Options Evaluation Matrix - Draft 8130100 P: Preferred N: Neutral
Open-Channel Piped Low Stream with
�✓�
Evaluation Criteria Low Flow Bypass Flow Bypass Backwatered Areas
Water Quality RS RS RS R�
Project must improve lake and downstream water quality,to assist Maintains stream Piped flows potentially Maintains stream Cc1 rr�cL2Z c�-e-
in meeting standards for temperature, bacteria, dissolved oxygen, temperature- Lake cooled by ground-Lake temperature-Backwater CW, I-'
nutrients, pH and chlorophyll. continues to receive a continues to receive areas may collect nutrients U
surface drainage during surface drainage during and slowly release in
low flows low flows summer months
Project must improve visual aesthetics (minimal weeds, algae Allows for chemical Allows for chemical Reduces stagnation
blooms) and reduce odors associated with lake water. treatment of aquatic treatment of aquatic impacts-Eliminates lake n
weeds weeds feature `
Neighborhood Impacts
Minimizes negative impacts(including property values) on the Minimal change in Minimal change in Reduced open water area
surrounding neighborhoods. current open watern current open water with new backwater
conditions .-F conditions features
Park Use
Project maintains a lake water feature as focal point of Summer Yes �1 Yes No lake water4eature
Lake Park. -f
Project maximizes present and future uses for the Summer Lake Yes Yes No lake water feature
Park in conjunction with the Summer Lake Park Management
Project allows for educational opportunities at the park to improve Yes Yes Increased educational
understanding of water quality and fishtwildlife issues. potential with more natural
habitat conditions �+
Page 1
r
Open-Channel Piped Low Stream with 1
Evaluation Criteria Low Flow Bypass Flow Bypass Backwatered Areas
Fish&Wildlife Habitat and Travel Corridors RS RS RS
Project creates a habitat where humans, fish and wildlife coexist. Some habitat dat created Increased habitat value
enhancement 'TCA-E -o-o-,I 14,43vk�-
Project encourages the growth of native species while Use of natives to No habitat created Most potential for native n
discouraging the presence of exotic invasive species. vegetate streambank plantings !
Project enhances fish and wildlife habitat including improving Improves passage for Fish passage through Major improvements for all
migratory passage for both. aquatic species pipe may be less optimal aquatic species y
than with other options
Re ulations
Project meets, or works toward meeting, all applicable federal, No violations Marginally acceptable Fully meets requirements
state and regional local regulations, including CWA, ESA, Goal 5
and Title 3 SA D&C standards). A A
Project satisfies DEQ, USF&WS, ODFW, NMFS, USACOE, DSL Yes Yes Yes
,requirements throu h their early involvement. A A oilf�1Q
Cost
Project is cost effective and affordable, for both construction and Medium cost. Medium Least costly. Least likely A Most costly. Most likely to Q
operations&maintenance,with available funding. potential for funding. to receive funding. A receive funding.
Project minimizes maintenance costs. Intake, fish ladder& Intake, fish ladder& Least costly to maintain
chemical treatment cost d� chemical treatment cost
Recommended Alternative Demonstrates That:
Interested citizens, City and Agencies shall have had the Yes Yes Yes
opportunity to work collectively on solutions.
Project proponents can pursue partnership funding through stream Moderate potential Least likely High potential
and habitat enhancement grants from government agencies.
The project can be monitored for effectiveness. Yes Yes Yes
The project has a high probability of successfully meeting the Yes Yes No lake water feature
objectives.
Page 2
Project Rambler/Bohmann Pond and Stream Enhancement (F-17)
• Location Fanno Creek-Between Rambler and Bohmann Parkway
Problem Creek straightened and unshaded. Excessive sedimentation in pond created by in-stream
dam and upstream sediment sources. Flooding of homes along creek
Est. Cost $509,000
Partners USA,Neighborhood Association
Conceptual Design Solution
Re-establish creek channel and make the pond off-line (model project). Excavate excess sediment buildup in
stream. Restore low-flow channel to historic meanders still present. Remove the south weir, re-configure the
north weir(which has a fish ladder),and extend the island in order to make the pond off-line. Enhance the site
with native riparian and emergent wetland vegetation. Residents who are floodprone have been advised to
flood-proof their homes. See conceptual map on back
2040 Flows
Design Flow Mode Points Drainage Area(Sq Mi) 2-yr 10-yr 25-yr 100-yr
&FMA 8.62 875 1290 1497 1773
&FMBS 8.62 897 1338 1551 1835
&FMB 8.37 889 1326 1537 1818
FMB S .099 20 30 34 40
• Plant Community
Riparian forest along creek
Emergent marsh and open water in off-line pond
See Technical Appendix A for more specific flow information, and "Model Sites and Enhancement Vision"
earlier in this section for specific plant community suggestions.
Issues
This project focuses on water quality enhancement and will not fully address flooding problems in the area.
However,the project may help reduce the frequency and severity of flooding.
The work should he completed between June I and September 30. A joint fill/removal permit will be required.
The project must be coordinated with Division of State Lands, Oregon Department of Fish and Wildlife, and
neighborhood association. USA must receive an easement over the pond and a permanent access point for
maintenance purposes. The Fanno Creek Neighborhood Association must contribute partial funding to the
Project.
Maintenance
Site Maintenance will be required until the native vegetation becomes established (3-5 years). Periodic
summer watering,plant protection, and monitoring of the site conditions will be a critical aspect of the project.
Fanno Creek Watershed Management Plan Section V 81
Rambler/Bohmann Pond and Stream Enhancement (F-17)
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Fanno Creek Watershed Management Plan Section V 82
CONSTRUCTION COST ESTIMATES
Open-Channel Piped Low Stream with
Low Flow Bypass Flow Bypass Backwatered Areas
Budget Level
Construction Cost $500,000 $400,000 $8001000
Estimates*
Operations and Medium cost to Highest cost to Least costly to
Maintenance Costs maintain maintain maintain
Would cost more to
operate and maintain
than the Open- j
Channel alternative
since there is a
potential for
sedimentation and a
pipe is more difficult to
clean out than an
open channel.
*Not including operations and maintenance