A fall septic checklist for Central Ohio before the freeze

October and November are the last easy weeks of the septic year in Central Ohio. The ground is still soft enough to dig, lawns are dry enough to carry a truck, and nothing is frozen yet. By January, a buried lid under frozen clay turns a routine visit into a chipping job, and a pump line that holds water can freeze solid. Here is a checklist to work through before that happens.

1. Decide whether the tank is due

Pull the last pumping report. If you do not have one, the tank is due. If you do, compare its date with the Ohio State University Extension table for your tank size and household: about 2.6 years for four people on a 1,000-gallon tank, 4.2 years on a 1,500-gallon tank, and shorter with a garbage disposal. If the next pump-out would land in January or February, move it up to this fall.

A fall pump-out also puts a current service report in your hands before the year ends, which is what many county operation permits look for.

2. Bring the lids to the surface

If the pumper has to dig to find your lids, fall is the time to fix that for good. Ohio's current rules call for watertight risers with at least a 12-inch opening and a lid that is heavy or fastened down, and fitting risers to an older tank while it is open for pumping is quick work. Once the lids sit at grade, a winter service call means brushing snow off a lid instead of breaking frozen ground.

If risers are not in the budget this year, at least mark each lid with a tall stake that will show above the snow.

3. Leave the grass a little taller over the field

Grass, and the snow it holds, is the insulation over your pipes. Set the last mowing of the year over the soil absorption area a notch higher than the rest of the lawn. Do not rake the field bare, do not strip it for a late seeding, and do not park anything on it. Compacted or bare ground freezes deeper than lawn under loose snow.

On a mound, check the cover. Ohio State describes a layer of soil fill spread over the whole mound to protect its pipes from freezing; if erosion has thinned that cover on the crown or sides, have soil and seed added while there is still time for grass to take hold.

4. Keep traffic off the field all winter

Snowplows, pickups, firewood deliveries, and snowmobiles all compress snow and soil over the field, and packed snow insulates poorly. Stake the edges of the field and the route of the line from the tank, and tell whoever plows your driveway where not to push snow. Never pile plowed snow on the tank or the field.

5. Check the lines that freeze first

The pipes most likely to freeze are the exposed or shallow ones:

• The building sewer where it leaves the house, if it runs through an unheated crawl space or garage.
• Any stretch of line under a driveway, where plowing strips the snow cover.
• The discharge line from a dosing or lift pump, if it does not drain back into the chamber between doses.
• Lines on a slope where erosion has thinned the cover.

For comparison, the City of Columbus building department lists 32 inches as its frost line depth for residential construction, and January at the Columbus airport averages just under 30 degrees in NOAA's 1991 to 2020 normals. A line with a foot of cover under a plowed driveway is the one to worry about.

6. Test the alarm and the pump

If the system has a pump chamber or an aerobic unit, press the test button on the panel and confirm the alarm sounds. Make sure the breaker is on and labeled. If nobody remembers hearing the pump run, have it checked during the fall pump-out. A failed float in October is a service call. The same failure during a January ice storm is an emergency.

7. Fix the leaks that run all night

A toilet flapper that seeps or a dripping faucet sends a trickle through the system around the clock. In summer that trickle is a hydraulic load on the field. In winter, a slow trickle can freeze in a shallow line before it ever reaches the tank. Replace worn flappers and fix drips before the cold sets in.

8. Plan for an empty house

If the house will sit empty for weeks this winter, the system loses the warm water that keeps it from freezing. Arrange for someone to run water regularly, or ask what else suits your system type before you leave. Never pour antifreeze into the system; it harms the bacteria the tank depends on and sends chemicals into the soil. For a rental or a second home, tape a card inside the alarm panel door with a phone number to call, so whoever notices the light knows what to do.

The short version

• Pump now if the tank will come due before spring.
• Raise or mark every lid.
• Leave the grass taller over the field, and keep traffic and plowed snow off it.
• Check shallow lines and pump discharge lines.
• Test the alarm and fix running toilets.

If the tank is due, book a fall pump-out while the ground is still easy to work. And if something is already freezing, the frozen system FAQ covers what to do first.