Septic pumping in McHenry County, Illinois costs $300-$650 (avg $450). A new septic system installation costs $6,500-$13,000. USDA soil data rates 0% of county soils as suitable for septic absorption fields. Approximately 7,445 homes in this county use septic systems.
Septic System Costs in McHenry County
| Service | Low | Average | High |
|---|---|---|---|
| Pumping / Cleaning | $300 | $450 | $650 |
| Routine Inspection | $250 | $350 | $500 |
| Real Estate Inspection | $450 | $650 | $900 |
| Minor Repair | $800 | $1,150 | $5,650 |
| Conventional Installation | $6,500 | $9,300 | $13,000 |
| Aerobic System Installation | $12,200 | $17,400 | $24,350 |
| Drainfield Replacement | $6,500 | $9,300 | $13,000 |
| Perc Test | $1,000 | $1,400 | $1,950 |
Cost estimates based on regional market data for McHenry County, Illinois. Actual costs depend on system type, site conditions, and provider.
Soil & Septic Suitability in McHenry County
Drainage Class
Well drained
Hydrologic Group
B
Unique Soil Types
82
Avg Bedrock Depth
2.9 ft
Dominant Soil Types
| Soil Series | Coverage | Drainage | Hydro Group |
|---|---|---|---|
| Kidder | 826 | Well drained | B |
| Ozaukee | 569 | Moderately well drained | C |
| Casco | 546 | Somewhat excessively drained | B |
| Kidami | 510 | Moderately well drained | C |
| Fox | 398 | Well drained | B |
Septic Tank Absorption Field Suitability
USDA NRCS rates soil suitability for septic absorption fields across this county:
Overall rating: Very limited
Groundwater & Water Table in McHenry County
Monitoring Wells
76
Avg Depth to Water
32.2 ft
Median Depth
21.6 ft
Shallowest Recorded
-9.9 ft Shallow Risk
Water table depths in this county are generally favorable for conventional septic systems.
Source: USGS National Water Information System. Based on 1646 measurements from monitoring wells.
Septic Regulations & Permits in McHenry County
State Regulatory Body
Illinois 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 McHenry County health department for current permit requirements, fees, and approved system types.
Septic System FAQ for McHenry County
How much does septic pumping cost in McHenry County?
Septic pumping in McHenry County, Illinois typically costs between $300 and $650, with an average of $450. 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 McHenry County?
A conventional septic system installation in McHenry County typically costs $6,500-$13,000. An aerobic treatment unit (ATU) costs $12,200-$24,350. 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 McHenry County?
Yes. Virtually all counties in Illinois 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 McHenry County health department for current requirements and fees.
What soil types are in McHenry County and how do they affect septic systems?
McHenry County has predominantly Kidder, Ozaukee, Casco soils. The dominant drainage class is Well drained with hydrologic group B. The USDA rates 0% of surveyed soils as "Not Limited" for septic absorption fields, 4.7% as "Somewhat Limited", and 95.3% as "Very Limited".
How often should I pump my septic tank in McHenry 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 7,445 septic systems in McHenry County, there are many local providers offering regular pumping services.
Can I install a conventional septic system in McHenry County?
It depends on your specific site. USDA soil data shows that 95.3% of soils in McHenry 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 ($1000-$1950) and soil evaluation are required before the county will approve a system design.
How long does a septic system last in McHenry County?
A well-maintained septic system in McHenry 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 (McHenry 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.
Data last updated: 2026-04-13