Septic Systems in Jefferson County, MO

Regulations, costs, soil data & local providers

Pop. 226,739 ~18.8% on septic ~17,051 septic homes Well drained soil

Septic pumping in Jefferson County, Missouri costs $300-$550 (avg $400). A new septic system installation costs $5,300-$10,650. USDA soil data rates 0% of county soils as suitable for septic absorption fields. Approximately 17,051 homes in this county use septic systems.

Septic System Costs in Jefferson County

ServiceLowAverageHigh
Pumping / Cleaning$300$400$550
Routine Inspection$200$300$400
Real Estate Inspection$350$500$700
Minor Repair$650$950$4,600
Conventional Installation$5,300$7,600$10,650
Aerobic System Installation$10,000$14,250$19,950
Drainfield Replacement$5,300$7,600$10,650
Perc Test$800$1,150$1,600

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

Soil & Septic Suitability in Jefferson County

Drainage Class
Well drained
Hydrologic Group
C
Unique Soil Types
68
Avg Bedrock Depth
2.8 ft

Dominant Soil Types

Soil SeriesCoverageDrainageHydro Group
Freeburg 592 Somewhat poorly drained C/D
Horsecreek 401 Well drained B
Menfro 377 Well drained B
Useful 328 Moderately well drained C
Sonsac 293 Well drained D

Septic Tank Absorption Field Suitability

USDA NRCS rates soil suitability for septic absorption fields across this county:

Not Limited (Good)0%
Somewhat Limited6.5%
Very Limited93.5%

Overall rating: Very limited

Source: USDA NRCS Soil Survey Geographic Database (SSURGO)

Groundwater & Water Table in Jefferson County

Monitoring Wells
3
Avg Depth to Water
94 ft
Median Depth
90.5 ft
Shallowest Recorded
64.2 ft

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

Source: USGS National Water Information System. Based on 62 measurements from monitoring wells.

Septic Regulations & Permits in Jefferson County

State Regulatory Body
Missouri Department of Health/Environment
Inspection Required for Home Sale
No / Varies
Nitrogen Reduction Areas
No
Advanced Treatment Required
No

Contact county health department for specific requirements.

Contact the Jefferson County health department for current permit requirements, fees, and approved system types.

Septic System FAQ for Jefferson County

How much does septic pumping cost in Jefferson County?
Septic pumping in Jefferson County, Missouri typically costs between $300 and $550, with an average of $400. 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 Jefferson County?
A conventional septic system installation in Jefferson County typically costs $5,300-$10,650. An aerobic treatment unit (ATU) costs $10,000-$19,950. Given the predominantly well drained soils in this area, some sites may require alternative system types. Costs include the tank, drainfield, permits, and labor.
Do I need a permit for a septic system in Jefferson County?
Yes. Virtually all counties in Missouri 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 Jefferson County health department for current requirements and fees.
What soil types are in Jefferson County and how do they affect septic systems?
Jefferson County has predominantly Freeburg, Horsecreek, Menfro soils. The dominant drainage class is Well drained with hydrologic group C. The USDA rates 0% of surveyed soils as "Not Limited" for septic absorption fields, 6.5% as "Somewhat Limited", and 93.5% as "Very Limited".
How often should I pump my septic tank in Jefferson 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 17,051 septic systems in Jefferson County, there are many local providers offering regular pumping services.
Can I install a conventional septic system in Jefferson County?
It depends on your specific site. USDA soil data shows that 93.5% of soils in Jefferson County are rated "Very Limited" for septic absorption fields, while only 0% are "Not Limited." This means many properties will require alternative systems such as mound systems, pressure distribution systems, or aerobic treatment units. A percolation test ($800-$1600) and soil evaluation are required before the county will approve a system design.
How long does a septic system last in Jefferson County?
A well-maintained septic system in Jefferson 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 (Jefferson County has predominantly well drained soils). 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

Population226,739
Est. Septic Homes17,051
Avg Pumping Cost$400
Drainage ClassWell drained
Septic SuitabilityVery limited

Common Septic Services

Pumping: $300-$550
Inspection: $200-$400
Repair: $650-$4,600
Installation: $5,300-$10,650

Data last updated: 2026-04-13