Microbiologists in California's Orange County use a wide range of microscopy and imaging techniques to examine the organisms within the local water supply. New laser and fluorescence systems could offer improvements. Water quality is a primary concern for researchers at the Orange County Water District in Fountain Valley, Calif., which was mandated by the sate to manage the water supply in the northern sector of the county. Although the district was established in 1933, it didn't assume responsibility for sampling and analyzing its own production wells until 1989, when it expanded and upgraded its water quality laboratory to deal with a growing population and increasing groundwater contamination risks. Now some 6 million gallons of water are pumped through the district's reverse osmosis membranes each day. Researchers in the Biotechnology Research Department's Image Analysis Facility study biological processes with a wide array of photonics equipment: various transmission and fluorescence microscopes, charge-coupled device (CCD) cameras, and lasers and other light sources. They use the myriad techniques to study biofilms that form on the surface of the polymer separation membranes that are used to purify water.