Household water treatment in Gilroy, CA.

The City of Gilroy supplies its homes from nine city wells in the Llagas Subbasin, a groundwater basin that Valley Water manages and recharges. Gilroy receives no treated surface water.

What Gilroy's 2025 water report shows

Gilroy's 2025 Annual Water Quality Report lists hardness at an average of 237 ppm, ranging from 174 to 271. Quarterly nitrate sampling in 2025 averaged 5.4 ppm, below the limit of 10, and total dissolved solids came in at 339 ppm. That is the scale that shortens the life of water heaters and dishwashers across the south county.

The way we work does not change from house to house. We look up the public data on your water, tell you what your home actually needs, and put it in for one all-in price.

What we fit in Gilroy homes

• A softener and carbon filter for the whole house, fitted on your main line, as the flagship bundle starting at $2,699 installed.
• Reverse osmosis under the sink for drinking water, and the part of the setup that deals with PFAS.

Done locally

In Gilroy we size the softener to the city's own hardness figures and fit it where the water line comes in, which on most newer homes is the garage wall.