(310) 628-9399

34.07° N · 118.10° W · WESTERN SGV

Plumbing guides for the valley

One valley, many water suppliers and building eras. These guides compare towns where it matters.

Mon–Sat · Monterey Park, Alhambra, Rosemead, San Gabriel and nearby

San Gabriel MtnsRio HondoMonterey ParkAlhambraSan GabrielRosemead

Valley-wide notes

Guides here look across Monterey Park, Alhambra, Rosemead, San Gabriel and the towns around them, and point out where the advice changes from one city to the next.

Four cities, side by sideCityMedian year builtTypical hardnessRosemead195997 ppm (SGCWD)San Gabriel195797 ppm (SGCWD)Monterey Park1963220 mg/L (city wells)Alhambraabout 1960240 ppm (city)Census ACS 2020–2024; 2025 water quality reports. Hardness depends on your supplier.
House age and hardness across four cities.