Based on the need to upgrade and replace some of the treatment plant facilities, the Lake Washington pilot study was conducted to assess the following: determine the suitability of high-rate processes for treatment of Lake Washington waters; assess the performance benefits of the newer high rate clarification technologies being tested; and, collect design criteria and data for the technologies being tested. This pilot program was designed to simultaneously evaluate the performance of three high-rate water treatment processes that include: dissolved air flotation (DAF); solids blanket clarifier (Super-P); and, ballasted clarifier (Actiflo). Includes tables.