If you have you been to the Nevada County Rood Center lately there’s a good chance that you noticed the construction taking place in the parking lot. What may not be obvious is that the site represents the first significant bio-engineered stormwater management project in the Yuba Basin: sections of asphalt and conventional landscaping are being replaced by a rain garden and bioswale designed to “slow, spread and sink” stormwater runoff. The installation of these features will catch, temporarily store, and purify storm water that normally flows into Deer Creek unpurified, carrying with it the parking lot’s sediment and pollution.
The project, spearheaded by American Rivers, is scheduled to be completed in August before the first major storm event of the fall. SYRCL, with its 10 years of water quality monitoring experience, has been charged with developing and implementing a comprehensive monitoring program to evaluate the effectiveness of these catchment features.
At the first sign of rain this autumn SYRCL staff will be ready for the first flush in which water containing all the parking lot’s accumulated oil, antifreeze, and other debris from the summer will be washed into the rain garden and bioswale. We will be monitoring how much of this water is directed into the catchment areas and collecting samples to be analyzed for oil and grease, nutrients, toxic metals, and E. coli bacteria to determine how well the features attenuate pollutants and purify water. Monitoring will occur at every major storm event thereafter with data to be collected on pH, dissolved oxygen, conductivity, turbidity, and total suspended solids.
SYRCL will also supervise and analyze the results of two simulated rainfall events staged to determine how much water each feature can hold. After reaching a capacity of approximately 25,860 gallons, storm water will begin to flow out of the rain garden and into Oregon Ravine through a culvert that passes below Hwy 49. To better asses the project’s influence on the water being discharged from the attenuation features, SYRCL has established a monitoring site on Oregon Ravine to measure water quality before and after the project’s completion. It is our hope to observe improved water quality conditions in this tributary of Deer Creek after the successful implementation of this exciting and innovative project.
To learn more about the Stormwater Management Project at the Nevada County Administrative Center (Rood Center) or to see pictures of the project go to https://www.theunion.com/article/20100630/NEWS/100629691/1001&parentprofile=1053
To learn more about SYRCL’s other water quality monitoring data, visit yubashed.org.