Water and sewer service in San Diego, where housing age varies block to block

Neighbourhoods like North Park, South Park, and University Heights carry housing from the 1910s through the 1940s, which means original galvanised supply and clay sewer laterals are still common there — galvanised corrodes along its whole length rather than at one point, and clay fails at the joints, which is where root intrusion gets its start. That combination is why leak and sewer calls from these older, established neighbourhoods skew toward whole-line questions rather than single-spot repairs. Further out — Clairemont, Mission Valley, Serra Mesa — postwar and mid-century tract construction is more common, often on slab foundations with copper supply, which shifts the likely problem toward slab leaks from mineral-driven pinhole corrosion rather than a failing service line. Canyon-adjacent lots, common across much of the city's topography, add their own wrinkle: a service line or sewer lateral that follows a canyon grade can be longer and deeper than a flat-lot equivalent, which changes both locating and access. San Diego's reported water hardness — roughly 216 to 284 parts per million total hardness depending on treatment plant and seasonal blend — applies city-wide and is the mechanism behind copper pinhole leaks regardless of which decade a given house was built in.