Modesto Regional Water Treatment Plant


The Modesto Regional Water Treatment Plant is owned and operated by MID. Completed in late 1994 and expanded in 2016, the plant provides a quality drinking water supply for Modesto area residents.

It now treats and delivers up to 67,000 acre-feet per year to the City of Modesto, supplementing the City’s groundwater supply. MID’s arrangement with the City is detailed in the Amended and Restated Treatment and Delivery Agreement (PDF).

The water source is the Tuolumne River, which begins high in the Sierra Nevada Mountains. At Modesto Reservoir, water enters the plant’s state-of-the-art treatment process that ensures the water supply meets or surpasses all state and federal drinking water standards now and in the future.