Statistical Modeling of Daily Water Temperature Attributes on the Sacramento River

The Sacramento River is the largest river in California, and an important source of water for agricultural, municipal, and industrial users. Input to the Sacramento River comes from Shasta Lake and is controlled by operators of Shasta Dam, who are challenged with meeting the competing needs of these users while also maintaining a cold water habitat for Endangered Species Act (ESA) listed winter-run Chinook salmon. The cold water habitat goals are constrained by the volume of cold water storage in the lake, which operators attempt to selectively deploy throughout the critical late summer/fall window. To make informed decisions about the release of this limited cold water resource, skillful forecasts of downstream water temperature attributes at the seasonal time scale are crucial. To this end, we offer a generalized linear modeling (GLM) framework with a local polynomial method for function estimation, to provide predictions of a range of daily water temperature attributes (maximum daily water temp...