Sinking ground or a sinkhole near the house
Sinkholes are part of the landscape around Murfreesboro. Many are broad, shallow basins that are simply how the land drains. The ones that worry homeowners are the new ones close to a wall.
What people notice
How it shows up in a yard
- A round or oval dip in the lawn that was not there last year, or an old one that has deepened.
- Soil that keeps dropping beside the foundation however often it is topped up.
- A hole with clean edges and no soil piled around it, as if the ground had been taken from below.
- Fence posts, a mailbox or a small tree starting to lean toward one spot.
- Rainwater that used to run off and now disappears into the ground at one point.
What the geologists say
The ground under Murfreesboro has openings in it
A U.S. Geological Survey study made with the City of Murfreesboro found sinkholes throughout the area, from a fraction of an acre to several square miles across. Rain soaks through a thin layer of soil into cracks and channels dissolved in the limestone, and the survey notes that much of the runoff in country like this flows to low areas in sinkholes.
Where water funnels downward it can carry soil with it, a little at a time, until the surface settles or drops. The same study watched sinkholes fill after heavy storms. Some emptied within days and some held water far longer. It also found that changes at the surface which send more water into a sinkhole can make its flooding higher or longer.
It may not be a sinkhole
Other things that make ground sink
Buried and forgotten
- A utility or sewer trench whose backfill has settled.
- An old septic tank, cistern or well that was never properly filled.
- Tree stumps and construction debris rotting away under the lawn.
Water from the house
- A broken underground downspout pipe washing soil out at one joint.
- A leaking water or sewer line. A plumber finds and fixes those.
- Roof water dumped at a corner, eroding the soil along the footing.
First steps
What to do when you find one
Keep clear of the edge
Keep children, pets, mowers and vehicles away from a hole or a fresh dip. If the ground is dropping as you watch, or the house is making noise, leave and call 911.
Measure and photograph it
Width, depth, distance to the house, and the date. Do it again after the next heavy rain.
Stop feeding it water
Move downspout outlets and sump discharge so they empty somewhere else.
Don't fill it yourself
Brush, rubble and loose dirt hide a hole without supporting anything, and whatever goes in can reach the groundwater.
Call the right people
A foundation repair company for the house if the hole is near it or the house shows cracks. A geotechnical engineer for the ground. Your city or the county if it is in a street, a ditch or a drainage easement.
Repair
The house and the ground are separate questions
Repairing the ground is geotechnical work. Depending on what an engineer finds, it can mean digging down to rock and plugging the opening with graded stone and concrete, or pumping grout into voids. Supporting the house is foundation work: piers carried down to limestone so the structure no longer depends on the soil that moved.
A foundation company will often bring in an engineer for both. Ask who is designing the repair and whose name will be on the drawings.
Questions
About sinkholes and houses
Will the city repair a sinkhole in my yard?
Generally a hole on private land is the owner's to deal with. La Vergne's Stormwater Department, for one, lists sinkholes on private property among the things outside its maintenance work. Ask your own city or the county about a hole in a street or public drain.
Do I have to tell a buyer about a sinkhole?
Tennessee law requires a seller to disclose a known sinkhole on the property in writing before a contract is signed. The buying and selling guide covers the rule.
A low spot in my yard holds water after rain. Is that a sinkhole?
Not necessarily. Many yards have low spots from grading. A dip that is new, growing, or swallowing water instead of holding it is the kind to have looked at.
One phone call
Speak with a foundation repair company near Murfreesboro
Mention the crack, the dip or the lean, name the room, and give the month you first spotted it. Whoever picks up belongs to a Middle Tennessee foundation outfit whose only tie to this website is the referral. They can pencil in an inspection and follow it with a written price.
A house that is cracking as you listen, a wall on the point of failing, gas in the air: everybody outside first, then 911 and the gas company.
Expect the call to be recorded. Two short pages cover the rest: who pays for referrals and what becomes of call details.