*2.3. Watershed Sanitary Surveys*

Watershed sanitary surveys are required under the California Surface Water Treatment Rule (SWTR) and are submitted to the CSWRCB's Division of Drinking Water, formerly the California Department of Public Health and the California Department of Health Services. In February 1988, the California Department of Health Services requested that a sanitary survey of the SWP be conducted to enable Department of Health Services and water agencies treating SWP water to appraise the effectiveness of the operation of existing water treatment plants and to adequately evaluate new treatment plant design requirements. The SWC decided to conduct a single survey of the entire SWP watershed rather than conducting independent surveys when they applied for new water supply permits or amended existing permits. As a result, SWP watershed sanitary surveys cover almost two thirds of the State of California, starting with the upper reaches of the Sacramento and San Joaquin River watersheds and extending to the terminal reservoirs of the SWP in southern California. Since 1990, SWP watershed sanitary surveys have nominally been conducted every five years; this 1990 survey and its updates are summarized in Table A1 (see Appendix A).
