From summer 2022 through summer 2024, scientists at SFEI conducted three parallel efforts to support the establishment of baseline conditions in the Pescadero-Butano Watershed to inform management related to the watershed’s 2018 Sediment TMDL Habitat Enhancement Plan. The Plan sets water quality objectives for sediment, intended to improve and protect beneficial uses, including water supply, recreation, and habitat for many species in the watershed. To meet these objectives, numeric targets were set for several metrics: the proportion of fine sediment in pools, overall substrate grain size, and large wood loading within the watershed.

The first of SFEI’s three studies was conducted in partnership with Balance Hydrologics, Inc. to develop rating curves for suspended sediment concentrations in Pescadero and Butano Creeks during high-flow periods. The next study aimed to improve our understanding of flow and sediment dynamics during low-discharge periods near the mouth of Pescadero Creek. Finally, a large wood survey protocol was developed in partnership with the San Mateo County Resource Conservation District to be used to quantify a baseline volume of wood in the bankfull channels throughout the watershed and provide the framework for monitoring over time to evaluate progress toward meeting wood loading targets.