Plumbing repair in Sammamish, WA

What Sammamish's numbers say about plumbing

Sammamish is one of the most established suburbs tracked here — 66,110 people (2025 estimate), down just 2.0% since 2020^[2]. On the map that's 20.4 square miles holding 3,236 residents per square mile, the 13th densest of the suburbs here; it sits entirely in King County, with ZIP codes 98075, 98074^[3].

With 13% of homes built since 2010 and 13% before 1980^[1], Sammamish's plumbing runs from brand-new supply lines and fixtures to aging pipe, original valves and water heaters past their rated life.

Mail to Sammamish goes through 2 ZIP codes — 98075 (46% of the city's land), 98074 (44% of the city's land)^[6].

The tracked suburbs closest by are Issaquah (3.5 mi S), Bellevue (5.5 mi W) and Redmond (6.8 mi NW)^[3].

13% of Sammamish's 22,610 housing units predate 1980 and 13% went up in 2010 or later^[1] — the lowest pre-1980 share of the 15 Seattle-area suburbs we cover; nearby, Issaquah (17%), Bellevue (47%), and Redmond (26%) predate 1980. The 54% built in 1980–1999 are at the age where original water heaters and valves get replaced.

The biggest single slice — 28% — was built 1990 to 1999, and the median home dates to 1994^[1]. Neighbours from the same era tend to hit the same plumbing problems at the same time.

Water from the sky is plumbing work too: 1 flood or flash-flood report within 10 miles over 2016–2025^[4], and FEMA logged 27 flood-insurance claims across Sammamish's ZIPs^[5]. Homes that take water need working drainage, sump pumps and backflow prevention.

72% of homes heat with utility gas, and 17% of households rent^[1].

Measured against the 15 suburbs on this site, Sammamish records the lowest pre-1980 housing share (13%)^[1], the highest gas-heat share (72%)^[1], the lowest renter share (17%)^[1], and the 2nd-newest housing (by median year built) (1994)^[1].