Septic Systems in Modoc County, CA

Regulations, costs, soil data & local providers

Pop. 8,700 ~14% on septic ~487 septic homes

Septic pumping in Modoc County, California costs $400-$750 (avg $550). A new septic system installation costs $7,550-$15,100. Approximately 487 homes in this county use septic systems.

Septic System Costs in Modoc County

ServiceLowAverageHigh
Pumping / Cleaning$400$550$750
Routine Inspection$300$400$550
Real Estate Inspection$500$750$1050
Minor Repair$950$1,350$6,600
Conventional Installation$7,550$10,800$15,100
Aerobic System Installation$14,200$20,250$28,350
Drainfield Replacement$7,550$10,800$15,100
Perc Test$1,100$1,600$2,250

Cost estimates based on regional market data for Modoc County, California. Actual costs depend on system type, site conditions, and provider.

Groundwater & Water Table in Modoc County

Monitoring Wells
5
Avg Depth to Water
149.1 ft
Median Depth
134.3 ft
Shallowest Recorded
3.8 ft Shallow Risk

Water table depths in this county are generally favorable for conventional septic systems.

Source: USGS National Water Information System. Based on 187 measurements from monitoring wells.

Septic Regulations & Permits in Modoc 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 Modoc County health department for current permit requirements, fees, and approved system types.

Septic System FAQ for Modoc County

How much does septic pumping cost in Modoc County?
Septic pumping in Modoc County, California typically costs between $400 and $750, with an average of $550. 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 Modoc County?
A conventional septic system installation in Modoc County typically costs $7,550-$15,100. An aerobic treatment unit (ATU) costs $14,200-$28,350. Costs include the tank, drainfield, permits, and labor.
Do I need a permit for a septic system in Modoc 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 Modoc County health department for current requirements and fees.
What soil types are in Modoc 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 Modoc 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 $750. 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 Modoc 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. Some counties in California have mandatory pumping schedules — check with your local health department.
How long does a septic system last in Modoc County?
A well-maintained septic system in Modoc 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.

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Quick Facts

Population8,700
Est. Septic Homes487
Avg Pumping Cost$550

Common Septic Services

Pumping: $400-$750
Inspection: $300-$550
Repair: $950-$6,600
Installation: $7,550-$15,100

Data last updated: 2026-04-13