San Mateo County
carpet cleaning
in all 20 cities

Most of San Mateo County drinks water that is not local. The San Francisco Public Utilities Commission runs the Hetch Hetchy regional system, which serves 2.7 million customers in San Francisco and, wholesale, through 26 agencies in Alameda, Santa Clara and San Mateo counties. The Bay Area Water Supply and Conservation Agency says 85 percent of that water is Sierra Nevada snowmelt held in Hetch Hetchy Reservoir and about 15 percent is local runoff captured in reservoirs. The commission adds that its local reservoirs may carry more hardness than Hetch Hetchy water, so the figure shifts with the blend.

The 2025 reports of Burlingame, Brisbane, Millbrae, San Bruno, Pacifica, Redwood City, East Palo Alto, Foster City, Belmont and the Cal Water districts all print the same regional row: hardness from 8.1 to 112 milligrams per liter, averaging 62, about 3.6 grains per gallon. Menlo Park Municipal Water reports an average of 60. Coastside County Water District, which serves Half Moon Bay, treats water at two plants and reports averages of 94 and 79.

The exceptions sit in the north and on the bay. Cal Water’s South San Francisco system, which serves South San Francisco, Colma, Broadmoor and a small part of Daly City, blends purchased water with local wells that average 384 milligrams per liter, about 22.5 grains per gallon. Daly City takes about 60 percent of its own supply from San Francisco and the rest from city wells. In East Palo Alto the O’Connor Tract Co-Operative Water Company’s wells measure 222 and 260, and the Palo Alto Park Mutual Water Company’s 2024 report lists 167. Hardness is dissolved calcium and magnesium, and no one should promise that a local tap changes how a carpet comes out; a full rinse is what counts in any water.

CAL FIRE’s Office of the State Fire Marshal sorts State Responsibility Area land into moderate, high and very high Fire Hazard Severity Zones, and released recommended updated maps for Local Responsibility Areas, which cover incorporated cities, in four phases between February 10 and March 24, 2025. San Mateo County Planning explains the two kinds of area and publishes a map of the unincorporated local zones dated February 24, 2025. City documents describe the same hills from the ground. Woodside’s newsletter says a lot of the town is in a very high fire zone, a Portola Valley memo puts about 60 percent of that town in a high or very high zone, San Carlos’ foothills west of Alameda de las Pulgas are designated Very High, Half Moon Bay’s Very High zones are the vegetated hills in its north, parts of Brisbane Acres are rated high-to-extreme, and Hillsborough requires fire resistant construction in its Wildland Urban Interface.

Smoke does not need a local fire. On September 9, 2020 the Air District reported wildfire smoke making skies look dark or orange across the Bay Area, and on November 12, 2018 smoke from the Camp Fire in Butte County blanketed all nine counties. The August 2020 CZU Lightning Complex burned 86,509 acres in Santa Cruz and San Mateo counties. The district’s advice is to stay indoors with windows and doors closed and, for a heavy event, to consider a HEPA air purifier or a MERV 13 or better filter. Afterward, rugs, upholstered furniture and drapes hold odor, and no one can promise a smoke-marked piece comes fully clean. The EPA does not recommend routine duct cleaning, though visible soot or debris at the registers changes the answer.

Federal housing estimates count 264,419 occupied homes in the county, and 41.5 percent are rented. Of 287,184 housing units, 40.5 percent were built in 1959 or earlier, the median year built is 1966, 55 percent are detached houses and 29 percent are in buildings of five or more. The cities pull apart. Burlingame has the oldest median home, 1957, and is one of four cities where renters are the majority, with Redwood City, East Palo Alto and San Mateo. Colma, Half Moon Bay and Foster City are the newest, with medians of 1990, 1979 and 1976.

At the other end, 98.5 percent of Hillsborough’s housing units are detached houses, 97 percent of Atherton’s and 96 percent of Woodside’s, and only 6.5 percent of Hillsborough’s occupied homes are rented. Apartments and move-outs drive carpet and sofa cleaning in the first group; rugs, drapes and upholstery drive it in the second. The county’s 22,765 vacant units include 3,358 held for seasonal, recreational or occasional use.