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Clarks Creek Vegetation Surveys Page 1 of 18 DEPARTMENT OF ECOLOGY ENVIRONMENTAL ASSESSMENT PROGRAM September 10, 2012 TO: Jenny Wu, U.S. Environmental Protection Agency Cindy James, Washington State Department of Ecology, WQ-SWRO Char Naylor, Puyallup Indian Tribe FROM: Stephanie Brock, Washington State Department of Ecology, EAP-WOS SUBJECT: CLARKS CREEK EFFECTIVE SHADE AND ELODEA Project Code: 13-013 The purpose of this project is to determine the percent effective shade needed to “shade out” elodea along Clarks Creek. Background EPA, Ecology, and the Puyallup Indian Tribe began development of the Clarks Creek dissolved oxygen (DO) TMDL with contractor, TetraTech, in August, 2010. The study found the DO impairments in Clarks Creek are a result of complex biological interactions driven by a variety of external factors, including • Urban runoff associated with impervious areas, which carry sediment and organic solid loads that increase sediment oxygen demand (SOD) and reduce DO in storm drainage, reducing the average DO. Urban runoff also causes increased channel erosion in the headwaters, further exacerbating sedimentation • Nutrient (phosphorus) loads in urban runoff, which promotes elodea nuisance growth, in turn enhancing siltation, contributing to SOD and reducing reaeration. Sediment loads also promote elodea biomass accumulation, because they provide a favorable substrate for elodea growth. Excess elodea growth results in diurnal DO depression. • Lack of riparian cover increases solar radiation that promotes elodea growth and also elevates water temperature, resulting in decreased DO saturation concentrations and reduced DO. TetraTech developed a QUAL2Kw model to evaluate these complex biological interactions and estimate the pollutant reductions needed in Clarks Creek to achieve water quality standards for DO and dissolved gases. Through modeling load allocations were established in the TMDL including control of elodea density. ---PAGE BREAK--- Clarks Creek Vegetation Surveys Page 2 of 18 TetraTech could not establish riparian shading targets with the model. Therefore, the purpose of this project is to develop a relationship specific to Clarks Creek between elodea density and percent effective shade to determine the required effective shade to “limit” elodea growth. Methods The relationship between elodea density and effective shade was established through field measurements. Ecology took hemispherical photographs and measured channel geometry and elodea mat data at twenty-one locations along Clarks Creek between the Washington Department of Fish and Wildlife (WDFW) trout hatchery and the 56th Street bridge (Table 1 and Figure It was important to complete the surveys prior to elodea cutting which was scheduled to begin on July 15, 2012. The surveys were completed using kayaks provided by the Puyallup Indian Tribe on June 11, 12 and 26, 2012 by Ecology and Puyallup Indian Tribe staff. Table 1. Clarks Creek sampling locations Site Name Site Description Latitude Longitude CC1 Clarks Creek below the foot bridge at the WDFW trout hatchery 47.18 -122.32 CC2 Clarks Creek upstream of the 12th Ave bridge at Clarks Creek Park 47.18 -122.32 CC3 Clarks Creek of the 12th Ave bridge at Clarks Creek Park 47.18 -122.32 CC4 Clarks Creek below 12th Ave, above the 1st bend after bridge 47.18 -122.32 CC5 Clarks Creek upstream of the Reese household 47.18 -122.32 CC6 Clarks Creek at the baseball fields and public access 47.19 -122.32 CC7 Clarks Creek upstream of the 7th Ave bridge 47.19 -122.32 CC8 Clarks Creek of the 7th Ave bridge 47.19 -122.32 CC9 Clarks Creek of DeCoursey Park outlet 47.19 -122.32 CC10 Clarks Creek ~675 ft from CC9 (above Pioneer bridge) 47.19 -122.32 CC11 Clarks Creek upstream of the Pioneer Ave bridge 47.19 -122.32 CC12 Clarks Creek of the Pioneer Ave bridge 47.19 -122.32 CC13 Clarks Creek at obstruction #21 47.19 -122.33 CC14 Clarks Creek at open area at WSU plot 47.2 -122.33 CC15 Clarks Creek at corner between obstruction #23 and #24 47.2 -122.33 CC16 Clarks Creek at Tacoma Rd bridge 47.2 -122.34 CC17 Clarks Creek upstream of Stewart Ave 47.2 -122.34 CC18 Clarks Creek 500 feet below 66th crossing 47.2 -122.34 CC19 Clarks Creek at/above second 66th crossing 47.2 -122.34 CC20 Clarks Creek upstream of the hatchery 47.2 -122.34 CC21 Clarks Creek at the 56th St. bridge 47.21 -122.34 ---PAGE BREAK--- Clarks Creek Vegetation Surveys Page 3 of 18 Figure 1. Clarks Creek Elodea and Hemispherical Photo Sampling Sites. ---PAGE BREAK--- Clarks Creek Vegetation Surveys Page 4 of 18 Hemispherical photographs were collected from the stream center (where possible) using protocols specified in Standard Operating Procedures for hemispherical digital photography field surveys conducted as part of a temperature Total Maximum Daily Load (TMDL) or Forests and Fish Unit technical study (EAP045 – Stohr and Bilhimer, 2008). If the channel was too deep to wade, the photographs were taken from as close to the center of the stream as possible. Figure 2 shows an example of a hemispherical photograph taken on Clarks Creek at the foot bridge at the state trout hatchery (site CC1). Figure 2. Hemispherical photograph taken at site CC1. At each site cross section, the following measurements were taken: • Latitude/Longitude • Stream wetted width and depth (ft) • Elodea density (percentage) • Substrate coverage by elodea (percentage) • Mat width (ft) • Mat depth (ft) Elodea density is defined as the density of the mat of elodea. In most cases, if an elodea mat was growing, it was 100% dense. Substrate coverage refers to what percentage of the substrate at a given cross section is covered by elodea. ---PAGE BREAK--- Clarks Creek Vegetation Surveys Page 5 of 18 The hemispherical photographs were analyzed in the office using HemiView Software © to calculate the effective shade at each site. Ecology’s protocol for processing the pictures and using the software is outlined in the Standard Operating Procedures for the computer analysis of hemispherical digital images collected as part of a temperature Total Maxiumum Daily Load (TMDL) or Forests and Fish Unit technical study (EAP046 - Stohr, 2008). Results Table 2 presents the field measurements collected at each site during the surveys. Please note, sites between the outlet of DeCoursey Park and the Pioneer Bridge and down to the 56th Street bridge have high levels of elodea growth as well as other unidentified aquatic plants. These sites also have high levels of reed canary grass which impede the active channel (in some cases, restricting a 70-foot wide wetted channel down to a 20-foot wide active flowing channel). Hard copies of the field sheets are available from Ecology upon request. Copies of the hemispherical photographs are included in Appendix A. Table 2. Field data collected at each site during the surveys. SiteCode Latitude Longitude Wetted Width Ave Wetted Depth Elodea Density Substrate Coverage Mat Width Mat Depth feet Percent feet CC1 47.18 -122.32 30 0.4 0.0 0.0 n/a n/a CC2 47.18 -122.32 45 2.4 100.0 44.4 20 3.0 CC3 47.18 -122.32 45 2.6 100.0 55.0 25 3.5 CC4 47.18 -122.32 *55/24 2.8 100.0 100.0 24 3.7 CC5 47.18 -122.32 53 2.8 100.0 37.7 20 4.0 CC6 47.19 -122.32 45 2.6 100.0 75.0 not measured CC7 47.19 -122.32 47 2.6 100.0 10.0 2 3.6 CC8 47.19 -122.32 40 2.9 100.0 50.0 20 4.0 CC9 47.19 -122.32 *75/50 2.3 100.0 75.0 38 4.2 CC10 47.19 -122.32 *70/30 2.6 100.0 100.0 30 4.5 CC11 47.19 -122.32 38 2.9 100.0 78.3 30 4.2 CC12 47.19 -122.32 49 2.9 100.0 84.5 41 CC13 47.19 -122.33 51 3.4 100.0 60.8 31 4.5 CC14 47.2 -122.33 *61/37 3.0 100.0 100.0 37 CC15 47.2 -122.33 *72/20 2.2 100.0 100.0 20 4.5 CC16 47.2 -122.34 26 2.8 100.0 25.0 4 4.8 CC17 47.2 -122.34 *63/14 2.6 100.0 75.0 14 3.8 CC18 47.2 -122.34 52 2.5 100.0 75.0 33 CC19 47.2 -122.34 similar to last cross-section, not measured CC20 47.2 -122.34 39 2.6 100.0 56.0 22 3.8 CC21 47.21 -122.34 29 2.8 100.0 38.5 11 3.0 ---PAGE BREAK--- Clarks Creek Vegetation Surveys Page 6 of 18 * Total channel width/active channel width Prior to the start of the project, it was believed that the relationship would be developed between effective shade and elodea density. However, if elodea is growing at a site on Clarks Creek, it is almost always growing at a density of 100%. Therefore, because field staff measured the percent that substrate was covered by elodea at each cross-section, this data was used to develop the relationship between site effective shade and elodea coverage. Figure 3 shows the relationship between percent effective shade and the percent of the substrate coverage by elodea at each sampling site. The trendline indicates that higher percent effective shade (x-axis) results in lower percent coverage of substrate by elodea (y-axis) on Clarks Creek. The square data point is an outlier that was not considered as part of the trendline. Figure 3. Relationship between percent effective shade and substrate coverage of elodea in Clarks Creek. Conclusions and Recommendations The purpose of this project is to determine the effective shade needed to “shade out” elodea on Clarks Creek. The data indicate a relationship between effective shade and y = -1.0471x + 100.44 R² = 0.6512 0.0 10.0 20.0 30.0 40.0 50.0 60.0 70.0 80.0 90.0 100.0 0.0 20.0 40.0 60.0 80.0 100.0 Percent Substrate Coverage Percent Effective Shade Relationship between percent effective shade and percent of substrate covered by elodea on Clarks Creek ---PAGE BREAK--- Clarks Creek Vegetation Surveys Page 7 of 18 elodea coverage in Clarks Creek. The percent effective shade could be calculated in two ways: 1. Percent measured in the basin where the elodea is The field staff only took hemispherical photographs and surveyed one sampling site where there was no elodea. The effective shade at the site was 78%. 2. Percent calculated by the regression equation (trendline) where the elodea is This yields an effective shade of 95.9%. It is recommended that the effective shade be determined based on the trendline calculated from the field measurements and effective shade determined for temperature TMDL studies completed in adjacent basins. Other Puget lowland streams, such as Bear- Evans and Green-Newaukum, indicate that based on Clarks Creek’s width and vegetation characteristics, an effective shade of 85% is plausible and should “shade out” elodea. It is recommended that field measurements, including hemispherical photographs and channel and elodea measurements, be repeated every 2-3 years to track progress as riparian vegetation is established along Clarks Creek and as the City of Puyallup continues to manage elodea growth through cutting and hand pulling. References Stohr, A. and D. Bilhimer, 2008. Standard Operating Procedures for hemispherical digital photography field surveys conducted as part of a temperature Total Maximum Daily Load (TMDL) or Forests and Fish Unit technical study. Washington State Department of Ecology, Olympia, WA. EAP No. EAP045. http://www.ecy.wa.gov/programs/eap/qa/docs/ECY_EAP_SOP_Hemispherical_%20Phot ography_Field_Survey_v2_0EAP045.pdf Stohr, A. 2008. Standard Operating Procedures for the computer analysis of hemispherical digital images collected as part of a temperature Total Maximum Daily Load (TMDL) or Forests and Fish Unit technical study. Washington State Department of Ecology, Olympia, WA. EAP No. EAP046. http://www.ecy.wa.gov/programs/eap/qa/docs/ECY_EAP_SOP_046Hemispherical_Phot ography_Computer_Analysis.pdf ---PAGE BREAK--- Clarks Creek Vegetation Surveys Page 8 of 18 Appendix A Figure A-1. Site CC1 - Clarks Creek below the foot bridge at the state trout hatchery. Figure A-2. Site CC2 - Clarks Creek upstream of the 12th Ave bridge at Clarks Creek Park. ---PAGE BREAK--- Clarks Creek Vegetation Surveys Page 9 of 18 Figure A-3. Site CC3 - Clarks Creek of the 12th Ave bridge at Clarks Creek Park. Figure A-4. Site CC4 - Clarks Creek below 12th Ave, above the 1st bend after bridge. ---PAGE BREAK--- Clarks Creek Vegetation Surveys Page 10 of 18 Figure A-5. Site CC5 - Clarks Creek upstream of the Reese household. Figure A-6. Site CC6 - Clarks Creek at the baseball fields and public access. ---PAGE BREAK--- Clarks Creek Vegetation Surveys Page 11 of 18 Figure A-7. Site CC7 - Clarks Creek upstream of the 7th Ave bridge. Figure A-8. Site CC8 - Clarks Creek of the 7th Ave bridge. ---PAGE BREAK--- Clarks Creek Vegetation Surveys Page 12 of 18 Figure A-9. Site CC9 - Clarks Creek of DeCoursey Park outlet. Figure A-10. Site CC10 - Clarks Creek ~675 ft from CC9 (above Pioneer bridge). ---PAGE BREAK--- Clarks Creek Vegetation Surveys Page 13 of 18 Figure A-11. Site CC11 - Clarks Creek upstream of the Pioneer Ave bridge. Figure A-12. Site CC12 - Clarks Creek of the Pioneer Ave bridge. ---PAGE BREAK--- Clarks Creek Vegetation Surveys Page 14 of 18 Figure A-13. Site CC13 - Clarks Creek at obstruction #21. Figure A-14. Site CC14 - Clarks Creek at open area at WSU plot. ---PAGE BREAK--- Clarks Creek Vegetation Surveys Page 15 of 18 Figure A-15. Site CC15 - Clarks Creek at corner between obstruction #23 and #24. Figure A-16. Site CC16 - Clarks Creek at Tacoma Rd bridge. ---PAGE BREAK--- Clarks Creek Vegetation Surveys Page 16 of 18 Figure A-17. Site CC17 - Clarks Creek upstream of Stewart Ave. Figure A-18. Site CC18 - Clarks Creek 500 feet below 66th crossing. ---PAGE BREAK--- Clarks Creek Vegetation Surveys Page 17 of 18 Figure A-19. Site CC19 - Clarks Creek at/above second 66th crossing. Figure A-20. Site CC20 - Clarks Creek upstream of the hatchery. ---PAGE BREAK--- Clarks Creek Vegetation Surveys Page 18 of 18 Figure A-21. Site CC21 - Clarks Creek at the 56th St. bridge.