The paper deals with the problems of placing and processing the formed sludge at water treatment plants. The analysis of water treatment enterprises as an object of negative impact on the environment in Russia and the Sverdlovsk region has been carried out. Currently, most waterworks do not organize reuse of washing water and the use of sludge dewatering technologies. Discharge of such water leads to contamination of water supply sources. The problem of treatment of a water sediment is rightly considered one of the least developed, the most technically complex and costly. The paper compares existing sludge dewatering technologies. An investment project is proposed to develop and implement an effective sludge dewatering system in conditions of decreasing the ecological load by eliminating the discharge of wash water into the environment. The feasibility study of the project is given and its ecological and economic efficiency is calculated.