Septic Permits & Costs in Northwest Arkansas

Do you need a septic permit in Northwest Arkansas?

Yes. In Arkansas, a new or altered onsite wastewater system needs a permit before any work starts, and permitting runs through the county health unit where the property sits. The state's guidance is to contact the health unit in your county and ask for the Onsite Environmental Specialist, who handles the application and the site evaluation.

Arkansas rule includes one narrow statewide exemption: a single residence on ten or more acres where every part of the sewage system sits more than 200 feet from any property line. Benton and Washington Counties have overridden it locally by ordinance, requiring a permit for a septic system on a tract of any size in their unincorporated areas, so the acreage exemption does not apply here. Either way, almost every ordinary lot needs a permit, so plan on one and confirm with your county health unit.

Who to call: Washington and Benton County health units

The permit and the site evaluation are handled locally. These are the county health-unit contacts for the two counties that cover most of Northwest Arkansas:

What the permit process involves

The process is built around the soil, not a stopwatch. Arkansas requires a soil pit evaluation rather than the older percolation (perc) test, because a pit shows the depth to rock, any impervious soil layers, and the seasonal high groundwater level, which is what actually decides whether and how a system can work on your lot. From there a designer draws a system sized to the soil and the home, an installer builds it, and the health unit inspects before it goes into service.

Site rules and setbacks

The rule homeowners run into most is the water-well setback: an onsite wastewater system has to sit at least 100 feet from a water well. The karst geology and the Illinois River and Beaver Lake watersheds under this region are why the state pays close attention to septic siting here, and it is why the soil pit and setbacks are enforced rather than waved through.

Permit fees

The Arkansas onsite wastewater rules set the permit application review fee by the structure's square footage: $30 for 1,500 square feet or less, $45 up to 2,000, $90 up to 3,000, $120 up to 4,000, and $150 for anything larger. An alteration, repair, or extension is $30. That's the state review fee only; design, soil evaluation, and installation are separate costs. Fees are set by the state rule, not by the contractor.

What a septic system costs to install here

What you pay depends almost entirely on the system type. A conventional gravity system is the low end. The aerobic treatment units (ATUs) that Northwest Arkansas's tight soils and karst often require cost substantially more. Rather than quote a blended average, we keep the current ranges, each tied to a named national cost guide, on two pages you can check: our septic tank installation costs breakdown and the free septic cost calculator. Both separate conventional from aerobic so the number matches your situation.

Maintenance: pump every 3 to 5 years

Once a system is in, the single most useful thing a homeowner can do is pump the tank on schedule. The U.S. EPA and the Arkansas Department of Health both recommend having a septic tank pumped every 3 to 5 years for a typical household. Skipping it is the most common reason a drain field fails early, which is the expensive repair. Our septic pumping page covers what that runs locally.

Who can design, install, and pump a system

Arkansas restricts each part of the work to people the state has registered for it, which is worth knowing before you hire:

• Design is done by a Designated Representative, which the state defines as a Professional Engineer, land surveyor, sanitarian, master plumber, or equivalent.
• Installation is restricted to a holder of the state's Advanced Septic Installer registration.
• Pumping and cleaning is restricted to a holder of the state's Septic Tank Cleaner registration, which requires passing a state exam.
• Soil evaluation is done by a state-approved evaluator; your county health unit can give you the list for your area.

Sources

• Permit requirement, statewide exemption, soil pit, 100-foot well setback, and who is registered to do the work: Arkansas Department of Health, Onsite Wastewater FAQs.
• Program overview and professional lists: Arkansas Department of Health, Onsite Wastewater.
• County ordinances requiring a permit on tracts of any size regardless of acreage, and the point-of-sale inspection rule: Washington County, Planning: Ordinances and Regulations.
• $30 to $150 review-fee schedule (Section 4.9.1) and the full rule: Arkansas State Board of Health Rules Pertaining to Onsite Wastewater Systems.
• Pump every 3 to 5 years and general maintenance: U.S. EPA, SepticSmart for Homeowners.

Frequently asked questions