Checking on the health of our watersheds
The Puget Sound watershed was originally covered in forests and wetlands that would naturally filter and direct the flow of water. As the population in the area increased, construction and man-made barriers have changed the flow of this rainwater. Now the rainwater is instead diverted to storm drains.
Stormwater runoff, excess water flowing during storm events, is a major concern for Puget Sound. As the rain falls and water flows through our communities, various toxins can be picked up along the way. These pollutants end up flowing directly into Puget Sound without any treatment. If water quality is poor in our watersheds, aquatic life and surrounding ecosystems both feel the effects.
As part of our Salmon Heroes and other programs, ESC has partnered with local schools to test our local waters. Our recent NOAA B-WET grant allowed us to expand the program, reaching more students and in turn, more sample days. Our main test locations included Miller and Walker Creeks in Normandy Park and the Cedar River in Renton. All three of these are salmon-bearing streams. While on site, students measured a number of factors to help determine if the water is healthy for the salmon. This leads to a discussion on how to prevent and decrease the pollutants from entering Puget Sound.
How do the students measure water quality? They test for six test factors using LaMotte low cost water monitoring test kits.
Dissolved oxygen is the oxygen that is present and dissolved in water.
Nitrate is a chemical nutrient needed by plant and animal life for growth.
pH is a measurement of the acidic or basic quality of water or other substances.
Phosphate is a chemical nutrient needed for plant and animal growth.
Temperature is a measurement of hot or cold.
Turbidity is the measurement of the clarity of water.
Throughout our 2017-18 Salmon Heroes field season, we measured these factors at our three major field sites. We also tested water at two other locations with certain classes, Clark Lake and Mill Creek, both located in Kent, WA. Neither Clark Lake or Mill Creek are current salmon bearing streams.
In general, our nitrate levels were below the range detectable in our test kits. Our five other test results are presented in the graphs below.
Summer Salmon Heroes
Thanks to a generous grant from National Marine Sanctuary Foundation (NMSF), we were able to work with Federal Way students and collect water quality data at two new sites this summer – PowellsWood Gardens and Dash Point State Park. The results from those tests are found in the charts below.
Overall, the water quality was good at the two sites based on the tests. The Dash Point State Park site had no macroinvertebrates, which was an indication of pollution that was not covered by the tests. Students concluded that the water is poor water quality for salmon at the Dash Point State Park site due to the lack of macroinvertebrates.
Big Picture Service Learning
Big Picture Middle School Students conducted monthly restoration at Seahurst Park removing the highly invasive English ivy and planting native
plants. These plants filter polluted stormwater and create more wildlife habitat in the park. Students also created interpretive signs and placed them along the trail so the public could learn a bit more about this project.
The 7th and 8th graders monitored water quality in the park by collecting aquatic macroinvertebrate samples and quantifying pollution tolerance index. Students found an average Pollution Tolerance Index of 19 indicating Potentially good water quality
The most prominent macroinvertebrates found while sampling:
Species Intolerant to pollution: golden stoneflies, little brown stoneflies
Species Moderately Tolerant to Pollution: free living caddisflies,
Species Tolerant to Pollution: Amphipoda, midges, black fly larvae, and aquatic earth worms.