San Diego's drainage systems were not designed for atmospheric river events, and those events are increasing along the California coast. The January 2024 atmospheric river produced flash flooding and storm drain backups across multiple neighborhoods. Coastal outdoor humidity can exceed 80% relative humidity in summer, requiring sealed environments with active dehumidification — not open-window drying.
Aging infrastructure drives most San Diego water losses: homes in North Park and University Heights built between 1920 and 1960 retain galvanized supply lines well past their service life. Copper lines in slab foundations pit early from San Diego's slightly alkaline municipal water, making slab leaks among the most common residential losses.
California homeowners insurance covers sudden accidental internal losses but excludes external flood damage — that requires a separate NFIP or private policy. Ask your contractor for IICRC S500 certification and moisture logs. Call San Diego restoration professionals now for 24/7 response.