Microsoft has agreed to lease the water treatment plant attached to one of its United States data centres to the area's municipal council.
The company said that the City of Quincy would pay an annual lease fee of $US10 ($A9.8) for the plant with the option to buy it outright in 30 years.
It will also reduce the water rates charges that Microsoft currently pays.
The lease means the city takes responsibility for the operation, maintenance and management of the plant.
Microsoft said the city plans to expand the facility for industrial re-use of wastewater, as the resource is relatively precious in that part of Washington State.
The Redmond giant still needs water to cool the first data centre it built on the Quincy site.
However, a newer facility adjacent uses airside economisers for cooling, reducing its reliance on water.
Microsoft said it was working on data centre designs that reduced its reliance on water for cooling.