How to find a buried septic tank around Little Rock

Plenty of people around Little Rock own a septic tank they have never seen. The lids are under a foot of grass, the last owner never mentioned it, and nobody thinks about it until the drains slow down or a pump truck driver asks where to park. Finding it before that day saves money: crews that have to hunt for a tank usually charge for the time and the digging. Here is the order that tends to work, from the paperwork to the shovel.

1. Ask the county health unit for the permit

Most systems put in under a permit left a paper trail with the Arkansas Department of Health, and the drawing in that file is the quickest way to the tank and the lines. ADH's answer to "where do I get a copy of my septic tank permit" is to call the health unit in the county where the property sits and ask for the Onsite Environmental Specialist. It helps to have the year the home was built, the subdivision name and lot number, and the name of the original owner or developer (ADH FAQ).

Phone numbers are in the department's local health unit directory. Our septic permits page explains the rest of what those offices handle.

Not every house has a file. Older systems, homes on large tracts that qualified for the state's acreage exemption, and anything put in without a permit may have no drawing at all. Then it comes down to the clues below.

2. Ask the people who would know

EPA's guide for home buyers lists the same short set of sources: the health department's as-built drawing, the lids themselves, a septic service provider who has worked on the system, and the seller (EPA homebuyer guide). An old pumping receipt often has a sketch or a note like "8 ft off back corner." If you know which company pumped it last, they may have the location in their records. Neighbors who built at the same time sometimes have the same builder's layout.

3. Read the house and the yard

• Follow the sewer pipe out. Go into the crawlspace, or look at the foundation, and find where the main drain line leaves the house. The tank sits out along that line, usually toward the lower side of the lot because the system runs on gravity.
• Look for a cleanout. ADH rules call for a 4-inch cleanout on the building sewer, so a capped pipe sticking out of the ground near the house tells you which way the line runs.
• Look for risers or lids. Systems built to the current rule have risers at least 12 inches across brought up to finished grade over the tank openings, so on newer homes the lids may be sitting in plain sight under a doormat or a planter.
• Watch the grass. A rectangle where grass browns out first in a dry spell can mark the tank lid area, and parallel green stripes farther out often trace the drain lines. Frost and snow sometimes melt off the tank first on a cold morning, too.
• Know the distances. The ADH setback table keeps a system at least 10 feet from the house, property lines and water lines and 100 feet from a well, which narrows down where a permitted tank could be (ADH onsite rules).

4. Probe carefully, or have it located

Once you have a likely spot, a thin steel probe rod pushed into the soil every foot or so along the sewer line will hit the tank's concrete top. Go gently. Call 811 (Arkansas 811) before you dig so buried electric, gas and cable lines get marked, and never lean into or climb into an open tank: the gases inside are dangerous. If the yard does not give it up, a septic contractor can run a small transmitter or camera down the cleanout and trace it from above, which is usually faster than digging test holes.

Aerobic systems are easier

If your house has an aerobic system, look for the control box and alarm light on a post or wall and the spray heads in the lawn; the treatment unit lids are usually at or near the surface, since ADH requires a monitoring contract with an assessment at least every six months. The aerobic service page explains those visits.

Once you find it

Write down the measurements from two fixed corners of the house, take a photo, and keep it with your pumping receipts. If the lids are buried, adding risers to grade makes every future pump-out and inspection quicker. And if you would rather not hunt at all, one call to the number on this page gets a licensed local septic contractor out to locate, uncover and pump it.

Questions people ask

How deep is a septic tank buried around Little Rock?

It varies with the lot and the age of the system. Many tank tops are within a couple of feet of the surface, but grading and added fill can put them deeper. Systems built under the current ADH rule should have risers brought to finished grade, so there is nothing to dig.

Can I find my tank with a metal detector?

Sometimes. Concrete tanks have steel reinforcing and some lids have metal handles, so a detector can help narrow the search, but plastic and fiberglass tanks will not show up. The permit drawing or a probe rod along the sewer line is more reliable.

Is there a charge to have the tank located?

Contractors set their own prices. Many fold locating into a pump-out if the tank is easy to find and charge extra for digging or electronic tracing when it is not. Ask when you book.