A city-owned reuse loop cut one data-center campus’s demand for potable groundwater.

Quincy is dry, and its drinking water comes from deep groundwater wells. Data-center cooling water was cycling four or five times before becoming mineral-rich blowdown that the municipal reclamation plant was not designed to handle. The city and Microsoft spent roughly a decade planning, building, and testing a separate reuse system.

Under a 30-year agreement, Quincy owns and operates the utility. EPA says Microsoft financed the $31 million capital cost and related operating costs, pays a monthly treatment fee, and accepts regular rate adjustments. Future users would have to pay connection, capacity, and operating costs of their own.

After cooling, blowdown moves through lime softening and ultrafiltration. Some water goes directly to blending; some receives additional softening and reverse osmosis. Treated water waits in a permeate tank, is blended to a target conductivity, and returns to the cooling towers. Concentrated salts go to lined brine ponds for evaporation and later disposal.

The system includes ten treatment systems and more than 30 miles of pipe. As of EPA’s account, only Microsoft’s campus was connected; east-side sites remained too expensive to connect.

EPA’s 138-million-gallon figure is an estimated reduction in potable-groundwater demand, not total water use. The utility also uses about 260 million gallons a year of Columbia Basin Project canal water, mostly in summer, and EPA says about 5% of annual make-up water remained potable groundwater. The canal is seasonal, and the system can switch back to groundwater when needed.

No recent independent public audit in Bright’s source set reports current evaporation, energy use, water quality, or additional connected campuses. This is a documented operating loop, not a water-free data center.