Baseline Water Quality Monitoring to support restoration efforts in the Cache Slough Complex, 2013-2021.

The Cache Slough Complex is an ecologically significant area, with many restoration efforts of various kinds set to take place within its boundaries. These efforts which are tied to regulations set forth by the Biological Opinion, will have unknown impacts to in‐stream water quality. For this reason, the Department of Water Resources’ Water Quality Assessment (WQA) unit developed a monitoring program to establish baseline water quality measurements to help understand the environmental impact of these restoration projects and ensure pre‐restoration water quality data is available to compare against post-restoration water quality. To do so, data was collected at various sites that represent all major inputs and outflows within the Cache Slough Complex from September 2013 to December 2021.