- The City of Florence, local stakeholders, and partner agencies recently formed the Siuslaw Estuary Partnership (SEP) to address threats to drinking water quality and fish and wildlife habitat in the lower Siuslaw watershed. The Sole Source Dunal Aquifer within the lower Siuslaw watershed, which supplies the City ’s drinking water, is characterized by rapid infiltration, a shallow water table, and hydrologic connection with area streams, wetlands, and the estuary. These characteristics make the watershed highly susceptible to contamination from surface activity in Florence, the only major urban center in the watershed, and to climate change. Possible sources of aquifer contamination include fuel storage tanks, septic tanks, stormwater runoff, pesticides, and fertilizers. Potential effects from climate change include altered precipitation patterns that increase winter flooding and decrease summer stream flows, increased air and surface water temperatures, and rising sea levels.
The SEP is funded by a 3-year US EPA grant and its objectives are: to collaborate, to conduct scientific investigations, to foster public education and stewardship, to protect water quality and quantity, to plan for ecological growth, and to protect wetlands, riparian areas, and key estuary wetlands. Many of these objectives led to a groundwater and surface water monitoring program to collect baseline data on water quality and quantity. A groundwater flow model was developed to provide hydrogeologic constraints. Sampling of 10 groundwater wells, located to reflect differing land uses and position along groundwater flow paths, and 2 streams began in October 2010 and will continue through November 2012. Parameters sampled regularly in one or both of the water types include: water temperature, conductivity, dissolved oxygen, pH, ORP, turbidity, E.coli, groundwater level, and stream flow. Periodically sampled parameters include nitrate, phosphates, volatile organic chemicals, inorganic chemicals, glyphosate,2,4-D, and caffeine. The SEP plans to use the data collected to respond to any contamination discovered, to monitor water quality and quantity over time, to develop sustainable water management practices, and to plan for potential future impacts of climate change. This initiative provides a model for addressing threats to water quality and fish and wildlife habitat using collaboration and scientific investigation.
- Presented at The Oregon Water Conference, May 24-25, 2011, Corvallis, OR.