Septic pumping in San Mateo County, California costs $450-$900 (avg $650). A new septic system installation costs $9,250-$18,500. Approximately 9,173 homes in this county use septic systems.
Septic System Costs in San Mateo County
| Service | Low | Average | High |
|---|---|---|---|
| Pumping / Cleaning | $450 | $650 | $900 |
| Routine Inspection | $350 | $500 | $700 |
| Real Estate Inspection | $650 | $900 | $1250 |
| Minor Repair | $1,150 | $1,650 | $8,100 |
| Conventional Installation | $9,250 | $13,200 | $18,500 |
| Aerobic System Installation | $17,300 | $24,750 | $34,650 |
| Drainfield Replacement | $9,250 | $13,200 | $18,500 |
| Perc Test | $1,400 | $2,000 | $2,800 |
Cost estimates based on regional market data for San Mateo County, California. Actual costs depend on system type, site conditions, and provider.
Groundwater & Water Table in San Mateo County
Monitoring Wells
3
Avg Depth to Water
232.2 ft
Median Depth
287.5 ft
Shallowest Recorded
39.6 ft
Water table depths in this county are generally favorable for conventional septic systems.
Source: USGS National Water Information System. Based on 4 measurements from monitoring wells.
Septic Regulations & Permits in San Mateo County
State Regulatory Body
California State Water Resources Control Board
Inspection Required for Home Sale
Yes
Nitrogen Reduction Areas
Yes
Advanced Treatment Required
In designated areas
OWTS Policy (2012). Inspection required before property transfer.
Contact the San Mateo County health department for current permit requirements, fees, and approved system types.
Septic System FAQ for San Mateo County
How much does septic pumping cost in San Mateo County?
Septic pumping in San Mateo County, California typically costs between $450 and $900, with an average of $650. Costs vary by tank size (1,000-1,500 gallons is typical), ease of access, distance from the pumping company, and how full the tank is. Most homeowners should pump their tank every 3-5 years.
How much does a new septic system cost in San Mateo County?
A conventional septic system installation in San Mateo County typically costs $9,250-$18,500. An aerobic treatment unit (ATU) costs $17,300-$34,650. Costs include the tank, drainfield, permits, and labor.
Do I need a permit for a septic system in San Mateo County?
Yes. Virtually all counties in California require a permit before installing, repairing, or replacing a septic system. The permit process typically involves a soil evaluation or percolation test, system design by a licensed professional, application to the county health department, and one or more inspections during installation. Contact the San Mateo County health department for current requirements and fees.
What soil types are in San Mateo County and how do they affect septic systems?
Contact the county health department for soil evaluation requirements.
Is a septic inspection required when selling a home in San Mateo County?
Yes. California requires a septic system inspection as part of the property transfer process. This typically involves a certified inspector evaluating the tank, drainfield, and all system components. The inspection cost in this area averages $900. If the system fails inspection, repairs or replacement may be required before the sale can proceed.
How often should I pump my septic tank in San Mateo County?
The EPA recommends pumping your septic tank every 3-5 years for a typical household. The exact frequency depends on tank size, household size, and water usage. A 1,000-gallon tank serving a family of 4 should generally be pumped every 3 years. With approximately 9,173 septic systems in San Mateo County, there are many local providers offering regular pumping services.
How long does a septic system last in San Mateo County?
A well-maintained septic system in San Mateo County typically lasts 25-30 years, though some components may need attention sooner. The concrete septic tank itself can last 40+ years, while the drainfield — the most critical and expensive component — usually lasts 15-25 years depending on soil conditions. Regular pumping every 3-5 years and avoiding excess water usage are the two most effective ways to extend system life.
Data last updated: 2026-04-13