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08/02/2000 - Packet RECD J U L 212000 Summer Lake Task Force MEMO TO: Summer Lake Task Force RE: Upcoming Task Force Meeting DATE: July 19, 2000 August 2, 2000 FROM: Vaughn Browk The next Task Force meeting has two main purposes: 1. Accept a set of criteria statements that will guide alternative development and selection. 2. Prepare alternative solution approaches for resolving Summer Lake issues. As per the Task Force request, we are inviting agency representatives to this meeting to provide assistance in making sure the alternatives meet regulatory and policy guidelines. Enclosed in this meeting briefing packet are the July 5 Meeting Minutes and a Criteria Statements review draft. This draft is identical to the one emailed and faxed earlier. Please review these documents and come prepared with questions, editorial suggestions and a willingness to work toward group agreement. Thank you for your participation on this project. Looking forward to seeing you on Wednesday "d the 2 s Summer Lake Task Force71 August 2, 2000 6:30-9:00 PM Tigard Water Building Agenda 6:30 Welcome and Meeting Purpose Vaughn Introduce Agency Guests Review Previous Meeting Minutes Approve Agenda and Format 6:45 Criteria Statement Review & Approval Task Force Rating System Framework Refine and Edit Statements 7:30 Alternatives Design Greg/Task Force Conceptual Approaches Options Development 8:40 Neighborhood Meeting Plan Task Force Identify Feedback Needs Date, Time, Location Meeting Format & Materials Task Force Role 8:55 Next Steps Vaughn Review Progress Schedule Next Meetings 9:00 Close Meeting Vaughn s Summer Lake Water Quality Enhancement Project . Alternatives Evaluation Criteria Review Draft 7/17/00 Mission Statement: "The completed project shall enhance the biological integrity of Summer Creek and its attendant wetlands while providing for a multi-use urban park". Water Quality • Project must improve lake and downstream water quality,to assist in meeting standards for temperature, bacteria, dissolved oxygen, nutrients, pH and chlorophyll. • Project must improve visual aesthetics (minimal weeds, algae blooms) and reduce odors associated with lake water. Neighborhood Impact • Project minimizes negative impacts (including property values) on the surrounding neighborhoods. Park Use • Project maintains a lake water feature as focal point of Summer Lake Park • Project maximizes present and future uses for the Summer Lake Park. • Project allows for educational opportunities at the park to improve understanding of water quality and fish/wildlife issues. Wildlife Habitat/Fish Passage • Project creates a habitat where humans, fish and wildlife coexist. • Project encourages the growth of native species while discouraging the presence of exotic invasive species. • Project enhances fish and wildlife habitat including improving migratory passage for both. Regulations • • Project meets, or works toward meeting, all federal, state and regional local regulations, including CWA, ESA, Goal 5 and Title 3 (USA D&C standards). • Project satisfies DEQ, USF&WS, ODFW,NMFS,USACOE, DSL requirements through their early involvement. Cost • Project is cost effective and affordable, for both construction and operations& maintenance, with city budget. • Project minimizes maintenance costs. Other • Neighbors, City and Agencies shall have worked collectively on solution. • Selected project has a high probability of successfully meeting the objectives. • • Project proponents can pursue partnership funding through stream and habitat enhancement grants from government agencies. • Project can be monitored for effectiveness. • Fishman Environmental Services, LLC CONSULTANTS IN ECOLOGY AND NATURAL RESOURCE MANAGEMENT Z 9, (� ; ao TECHNICAL MEMORANDUM Date: April 27, 2000 To: Kendra Smith, USA From: Steve Johnson, Senior Fish/Aquatic Ecologist; Kim Gould, Fish/Aquatic Biologist Subject: Summer Creek/Summer Lake Ecological Viability Analysis Introduction Fishman Environmental Services was asked to prepare a brief analysis of existing habitat and water quality conditions in Summer Creek upstream of Summer Lake and address a series of questions regarding feasibility and relative probability of success of the management alternatives posed by the newly-formed Summer Lake Task Force. This memorandum describes the results of our survey and our recommendations for addressing the water quality concerns at Summer Lake. Methodology Steve Johnson and Kim Gould visually surveyed Stunmer Lake and the south fork of Summer • Creek from the lake upstream to the headwaters above the quarry. Water quality measurements (temperature, dissolved oxygen,pH, and conductivity were taken with an ICM model 51501 Aquacheck water quality meter. Analysis The survey and analysis conducted by FES was designed to address the ecological conditions and limitations of the south fork of Summer Creek and Summer Lake in relation to the habitat , requirements of resident coastal cutthroat trout, Oncorhynchus clarki clarki. We have attempted to address several of the key questions pertaining to the potential breaching of the dam, enhancement of habitat conditions upstream in the creek and augmenting flows in Summer Creek with groundwater from the quarry. Existing Conditions of Summer Lake and Summer Creek Water quality conditions in Summer Lake are currently visibly as well as physically degraded. Water quality measurements taken on April 19, 2000 indicated that water temperatures were approximately 3° C warmer in the lake (18°C)than two miles upstream near the powerline corridor(15.4°C). In addition,pH values were considerably higher in the lake than in upstream reaches of the creek (lake: 8.64; quarry reach: 7.41). Oregon DEQ 303 (d) General Basin Standards (adopted as of 1/11/96) for pH in the Willamette Basin are 6.5 to 8. . Dissolved oxygen values were acceptable both in the lake and in the creek. The riparian and wetland vegetation is better developed along the southern edge of the lake which includes a broad • wetland fringe (dominated by reed canarygrass) and shrub layer with an adjacent stS°d of 0 o'-'q 434 NW Sixth Avenue, Suite 304 Portland OR 97209-3600 phone:503 224 0333 fax:503 224 1851 www.fishenscrv.com Summer Lake/Creek Ecological Viability Analysis April 27, 2000 • Page 2 conifers. The wetland/riparian vegetation on the north side is limited to a strip approximately 15- 20 feet wide and provides some protection for wildlife but little in terms of shade benefits. Upstream of the lake between Scholl's Ferry Road and the 1301h Avenue bridge, Summer Creek meanders through a broad floodplain dominated by reed canarygrass,however segments of the channel are covered by a dense canopy of willow and a variety of native shrub species. Most of the coniferous trees along this reach are dead, possibly from periodic flooding or excessively wet conditions resulting from beaver activity. The riparian canopy of mature trees is still intact through the Reflections at Summer Creek development reach. The stream channel is somewhat wider(8-10 feet versus 3-5 feet)than in downstream reaches. Beaver activity at the upstream end of the triple culvert road crossing in the Reflections development has created an impoundment in recent years. Upstream of Reflections,the floodplain broadens again and the channel becomes braided. Once again, most of the mature trees through this reach are dead or dying. An instream detention pond downstream of the powerline corridor appears to be a potential problem in terms of temperature impacts. The pond is shallow and has insufficient shading to prevent warming of impounded waters. Conditions in Summer Creek above the detention pond do not provide adequate fish passage • particularly where the creek passes over the powerline access road, at the culverts downstream of the quarry access road and at the beaver dam upstream of the quarry. There appear to be small pockets of adequate fish habitat including gravel and sufficient instream and canopy cover both above and below the powerline corridor. Recommended Potential Actions to Bring Summer Creek into Compliance It is apparent that while specific water quality improvement goals, such as removal of phosphorus through detention facilities, are attainable, they may conflict with other desireable goals such as reduction of stream temperatures or improved fish passage. Restoring adequate temperature and water quality conditions in Summer Creek to support salmonids,particularly cutthroat trout, will likely require a combination or possibly all of the watershed management alternatives presented in the Summer Lake Management Plan as well as flow augmentation from the quarry. Separation of Summer Lake from Summer Creek and removal or partially breaching of the dam are the most ambitious and likely most expensive of the alternatives. These alternatives should continue to be considered and studied for later use particularly if the less expensive options such as flow augmentation and enhancement tree and shrub planting are found to be reasonably effective and further compliance measures are warranted. Shrub planting has a greater probability for success for providing shade than tree planting based on the width of the stream channel. Shrubs will likely provide more immediate shading results and are less likely to be removed by beaver. Good examples of reaches with good shrub canopy cover are located upstream of the 1.3 Avenue bridge and upstream of the bridge • in Reflections at Summer Creek. i Summer Lake/Creek Ecological Viability Analysis • April 27, 2000 Page 3 Modifying the lake by separating it from the Summer Lake stream channel will likely provide considerable benefits to downstream water quality in terms of temperature reduction, however it would be of little value unless the temperature criterion can be met upstream of the lake. It is important to note that if the lake is taken off-line many of the recreational and aesthetic benefits of the lake will remain intact and possibly improved through chemical treatment, augmentation with freshwater water or deepening through dredging. (If this doesn't work you might consider building paddle boat marina to provide shade and increase dissolved oxygen levels!) Additional Measures (not included in Management Plan) to Improve Fish Passage and water Quality Instream obstructions resulting from beaver activity appear to be on the rise. While beaver ponds are generally beneficial in terms of wildlife habitat, they tend to create fish passage problems and the shallow impoundments can act as heat sumps that release warmer water into the downstream reaches of the creek. The dams allow additional water volume to be stored on the floodplain and facilitate groundwater recharge in the summer months. Augmentation planting around the edges of beaver ponds,protected against destruction by beaver, may help reduce temperature conditions during the summer months. • Extent of Urban Runoff During Summer Months Concerns have been expressed that the extent of impervious surface (paved areas and roofs) in the Summer Creek basin precludes effective water quality restoration. The Summer Creek basin's area is approximately 36 percent impervious surface (Ecotrust 1998). Although this percentage is considered high enough to have considerable effects on basin hydrology, the Summer Creek Basin possesses approximately 10 percent less impervious surface than adjacent watersheds (Sylvan Creek: 45%; Ash Creek: 46%). The storm hydrograph for a precipitation event in such an urbanized basin would be expected to exhibit a higher and earlier peak than in a comparable basin with less impervious area(i.e. the stream would have a more "flashy" hydrology). This effect can be partially mitigated by modern stormwater detention facilities. Given that the Summer Creek system possesses less impervious surface and more stormwater detention facilities than adjacent basins, it would be expected to have a somewhat less"flashy" hydrology. Detailed hydrological modeling would be needed to specifically estimate these effects. Expected Effectiveness of Flow Augmentation and Infiltration to Reduce Stream Temperatures Above and at the Lake Flow augmentation and infiltration appear to be the best opportunities to determine whether the target temperature range (64° F), is attainable. Flow augmentation can likely be accomplished fairly inexpensively providing the discharge point is in the vicinity of the quarry rather than 2 • miles downstream at Summer Lake. A series of temperature monitors strategically placed in the three forks of Summer Creek will provide a good indication of whether this alternative alone will Summer Lake/Creek Ecological Viability Analysis April 27, 2000 • Page 4 be adequate to meet the temperature goals. If the data show that acceptable temperatures of 64° F are unattainable upstream of the lake, it makes little sense to remove the dam and provide passage for salmonids. Timing and Sequencing of Proposed Actions Feasibility and design study of Summer Lake/Dam modifications should continue to be examined since it is recognized that a partial breach of the Summer Lake Dam will require 5-7 years for regulatory approval. While these actions are explored, less expensive actions, such as tree and shrub planting, can take place in reaches that currently lack adequate cover. Implementation of these activities will give an indication of whether the water temperature criterion is attainable in Summer Creek. Range of Costs The relative cost of alternatives under consideration from least to most expensive are likely as follows: • Enhancement tree and/or shrub planting through the City's Adopt-a-Stream program • Flow augmentation through pumping • • Removal of instream detention facilities (other than Summer Lake Dam) • Partial breaching of Summer Lake Dam • Moving Summer Lake offline from Summer Creek • s Exhibit A • SCOPE OF WORK AND SPECIAL TERMS AND CONDITIONS I. Scope of Work: Consultant shall analyze the condition of Fanno Creek and the basin draining to it from the Summer Lake dam upstream to the quarry. Consultant's evaluation shall address the following issues: • What are the conditions of Summer Lake and the mainstem reach above it up to the quarry? • If the conditions above the Lake do not meet standards (water quality and fish passage), are there actions that could be taken to bring the reach into compliance? • What are the measures that should be taken upstream(beyond those identified in the watershed plan and recent development plans)to improve water quality and fish passage,if any? • What is the extent of urban runoff heating the creek during the summer months? • What is the expected effectiveness of the proposed measures (flow augmentation in the upper reaches from groundwater and infiltration at water quality facilities to reduce stream temperatures above.and/or into the lake? • • What would be the appropriate timing and sequencing of the proposed work for areas upstream and the Lake? Should implementation of the Lake modification await resolution of the problems upstream? • What are the range of costs associated with the needed activities? Describe the economic efficiency of the suggested improvements? I�