Sinkhole & subsidence warning sign FAQs:
Questions & answers about detecting and taking action on suspected sinkholes developing at or near buildings.
This article series describes the visual signs that a sinkhole is likely or is already developing in an area: sinkhole warning signs.
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On 2017-10-08 by (mod) - decide if you need further sinkhole expertise or a geotechnical engineer
Start by taking note of the country, state, province, or city where you live, then search for sinkhole information for that specific area. If you live in an area prone to sinkholes then you may indeed want to hire a geotechnical engineer to consult about your site and home
. If you are not in a natural sinkhole areas then sinkholes can still occur due to underground leaks, subsidence over buried trash, etc. and you still need assistance. But the diagnosis and cure recommended by a local mason experienced in foundation repair may be sufficient.
The contractor, in turn, should help you decide if engineering help is needed. We can't make that assessment by a text query.
On 2017-10-08 by Qianna Aragon
Ive lived here for about 11 years and just in the last 4-5 months ive noticed the cement walkway sort of lifting at certain seams then in a couple days id see it now downward at the seams
And i notice this because im a smoker and ive told my boyfriend enough for him to tell me stop im sounding weird then i mentioned it to our landlord ((Wife)) the 3rd time i told her i actually got her to come back and look she agreed but forgot to mention it to her husband((he would have been on it))
Anyways im really scared after reading just 2 articles ofrom google and seeing all the signs...
Im almost certain thats what we have..Come to think of it our neighbors recently took their pool out because it got a crack underground...hmm
How do i go about this if im not theowner of the home
I cant sleep at night..
On 2017-10-01 by Loretta
Our property has a colvert that runs under a section of our parks no area. On either side of our property sink holes have formed, one in the street itself has reoccurred three times and the highway dept just fills it in with asphalt even though a stick through the hole showed about three feet of nothing between the road and colvert pipe.
Now I am noticing two pines and a white birch on my property in this area are all dying and turning brown and wonder if this could be from the ground collapsing deep down under the roots.
On 2017-07-30 by Kathy
We had heavy rain last night, a small area (where I drive) has always been a little low, today there are bubbles coming up out of the ground. Small bubbles but has been going for over 5 hours that I know of. What could that be? (I do not have gas)
On 2017-07-29 1 by Michael Pelletier
Am I correct a sinkholes supposed to be disclosed before you buy the house my neighbors are telling me and I've seen where they filled the hole in and we just recently bought the house I'm concerned
On 2017-07-24 by (mod) -
I appreciate the interesting question but honestly I think an on-site excavation contractor can look around at the lay of the land, drainage directions, easements, other properties that may be affected by runoff, and can make a far better and safet prescription than I could by e-text.
On 2017-07-21 by jdswanger84
My wife manages an apartment complex im goin to try and explain the landscape and the problem and hopefully get answers on the best fix.
There are two building on the left side of the property each building is 120 ft longwith a 60 ft gap in between totaling a 300 ft property line behind the building the propertl line is a 6 ft tall mound of dirt that runs the coplete length of the property.
On the mound is a row of 13 pine trees.. there is a driveway on the other side of this mound that goes over the hill to the house at the bottom on the ajacent property so you get the idea we will say the elevation on the apartment building is 110 ft and up across the mound and down over the slope set the neighbors house at 100 ft elevation
the lowest point of the apartment is dead center of this 300 ft mound at 150 ft mark.
No drain were ever installed so ove time at rain and water runoff has washed away the ceter of this mound and erosion has crept to withing 20 ft of the apartments. I was wondering whats the best fix a tstorm drainige syster and build tje mound back or storm drain system and a retaining wall
On 2017-03-27 by (mod) -
I can't guess by e-text whether or not you are seeing a true sinkhole or more common settlement over fill and marsh.
But Illinois does have some Karst formations and sinkholes, as the Illinois State Geological Survey reports at
You might want to start with your local building department to ask them to look at the site and give advice, and also to ask if there are known sinkholes or karst formations in your immediate area - else the hole is from something else.
On 2017-03-27 by Vicki Kea
Hi, I live in a small village in Northern Illinois. When this area was settled in the 1800s it was a marshy area. From what I understand, the water was pumped out and the village was built. That being said, the ground on our one-acre property is very uneven.
The house is 118 years old and is built up on a mound. We have lots of low spots that collect rain water and then slowly is absorbed back into the ground. We also have two sump pumps in the basement that work non-stop. One spot that worries me is that on the parkway between street and sidewalk (village property) we have a very low spot that collects rain water.
mething like this? We want to place pavers there so we have a place to park out of the mud, but I'm concerned with the current condition of the area. It would have to be first leveled and then prepared for the pavers properly. This is not a DIY job. We bought the house two years ago. We have found that the storm drains for the village are in poor repair, broken and/or backed up with debris. We live on IL 173 and there is heavy truck traffic with lots of vibration. We don't know where to start to have this checked out. Thanks for any info.
On 2017-02-03 by DJ Hello
three years ago the repaved our road. the contractor reported to the township there is a sink whole in the street/also on my property (township not aware). How do I have it tested?
Do I get a report from township and get lawyer it's getting real scary don't want to have to mow over there this year.
On 2016-12-06 by Matt Turner
Ground Penetrating Radar can be used to detect sinkholes. Ground Penetrating Radar makes an underground image of sinkholes before they collapse.
On 2016-07-27 1 by Danita Aguon
We've been in our home for five years now and over the years I've noticed cracks in our driveway our brick walls have cracks in them that are plentiful driveway has cracks in a newly poured which is 5 years old or so. Our driveway is on the side of the house leading to the back yard where we have a 2 Story granny flat, 3 car garage and I noticed cracks on the concrete and the concrete wall that separates my neighbor and I.
With the cracks so that I see coming up on the driveway and on the concrete wall I am very concerned that I might have a sinkhole but I am not sure and I want to know what to do to relieve my anxieties about that if you can please help me I would really appreciate it
\ I've tried to get my husband to investigate the problem but he says that is normal but my husband is not a Geo tech so if you can tell me what I could do to see if we do actually have a sinkhole so I can be of sound mind thank you.
On 2016-05-30 by (mod) -
Sharon, I found a little history, not much, of the historic mud bog explosion in Winder Georgia, often referred to as a " mud volcano ", but not much scientific data; some texts posit that the Nodoroc mud explosion in Winder was due to decaying organic matter (leaves for example) in the bog.
If that was the case, it could certainly have been a methane explosion, though what ignited the methane gas is not stated. Certainly natural forces might ignite marsh gas as might a lightning strike.
Separately from the Nodoroc mud volcano, you describe a more recent bursting of a dam in about 2014. I haven't found references to that event. You might want to see the DeKalb County, Georgia Multi-Jurisdictional Hazard Mitigation Plan, February 2011, available from the DeKalb County government at http://dunwoodyga.gov/
If there was a sudden flooding of the site where your home is located there could have been damage to your home including its foundation.
It is, however, very unlikely that substantial foundation damage or movement could occur at your home, particularly as it is a brick structure, but with no visible evidence such as foundation cracks, building areas out of level, interior cracks, or other damage. Certainly enough house movement to make you feel "the bottom dropping out from under [your] feet" would be visually apparent on the home itself.
I can thus suggest these steps:
1. ask for a local inspection of the visual condition of your home and site for evidence of structural movement or damage
2. be sure that you have working CO detectors and smoke detectors, and ask your inspector to screen the site for presence of high levels of methane or other combustible gases
3. check with your doctor about any health conditions that might explain the conditions you describe
On 2016-05-30 by Sharon
Hi, I'm scared to death in Winder,GA. I live at the site of an inactive (at least at the moment & not since it's last week eruption in the 1800s which killed everyone in a 10 mile radius.) Mud volcano. Our yard is pasture and woods except right up by the house from the foundation out 10 feet is peat moss and lately I've been feeling like the bottom is dropping out from my feetwhile I'm in the house. It's a three story govornors mansion style brick home built in 1967.
Almost everything is just how it was back then except the wash down slope to the side that used to lead to a huge lake wehad out back about two football fields behind our house and suddenly about a year and a half ago the damn brokeand the water went somewhere but the lake is now gone not to mention there's black quicksand down around the area outside the crater a little ways which was already there.
The Indians called this place the gateway to hell and it used to be a burning swamp. Is this house on top of a sink hole cause I'm really certain that it's not safe but I can't convince anyone to listen inside our home. Help me please
(Aug 20, 2011) Jackie Venable said:
What resources does a homeowner have when insurance company will not inspect the property and refused to cover any damages?
Jackie, you may need to consult an independent insurance adjuster who will function as your advocate. S/he will in turn charge a fee, hire experts to evaluate the problem and basis for your claim, will negotiate with the insurance company in your behalf, and generally annoy them.
(Mar 13, 2013) Anonymous said
A brick just fell though and there ia sand about six inches below. It ia a sidewalk. What do u think
I think you should rope off the area and ask the city to take a look - could be a water main or other thing undermining the walk - you haven't said where you area or if it's a sinkhole prone area.
(Jan 28, 2014) Anonymous said:
My street has 30 cracks from one curb to the neighbors across the street. How do I get someone out to inspect them?
Call your city building department
(Feb 18, 2014) Anonymous said:
I am starting to see areas in my back yard that appear to be sinking. I have been watching them for a few months and they appear to be getting larger. What should I do?
(Mar 7, 2014) lee said:
there is a crack coming in the back yard seems to be getting wide quite quickly also around the foundation of house in same area the ground is sinking near the foundation leaving a wide gap all happening quickly we don't live in a comon sink hole area
Anon you don't say where you live - in some areas sink holes are a common and serious hazard
But just from your description it sounds as if you ought to
1. from a good distance away rope off or prevent access to the sinking area immediately
2. call your city building department and ask for an onsite inspection and advice
If you want to send us photos using the CONTACT link found at page bottom or top I may be able to comment further; do keep us posted.
There are lots of causes of sudden subsidence besides a geological formation associated with sinkholes; examples are underground water piping or sewer line leaks, buried stumps and trees, or collapse due to mining activity; for safety it would make sense to ask for help from your building department as a start, and to rope off or keep people out of the area.
(Mar 12, 2014) Anonymous said:
My husband stepped into a hole yesterday that was approx. 1 Ft. deep. We have had smaller ones outside under our large weeping Willow tree. Our neighbor has a underground well close to our home, which is close to our Weeping Willow tree. (75 ft.). The hole he stepped in was close to an entrance to his building outback.
He had to put something over it until he can fill it in. He has filled other holes up in the past. Our house has a door that won't close right, and a crack in our ceiling over the same door, (The crack has been there for years, but is getting worse, and in the garage ceiling.
Last year it was my sons bedroom door that was hard to shut, but it is okay now. Just was wondering what could be going on. Thank you. Sandy
I live in Eastern Daviess County Ky. Thanks
Sandy, if it were just a small hole opening up in a yard I might suspect settlement around old buried debris.
But when you add that a door no longer closes and the ceiling is cracked, those suggest more serious foundation settlement - enough that it's worth having a more expert assessment. Foundation settlement can occur due to sinkholes but also due to soil compaction combined with water movement (roof spillage, surface drainage, underground water etc).
Certainly sinkholes do occur in Kentucky. Recently (3/5/2014) the Washington Post reported that a sinkhole opened beneath the Corvette Museum in Bowling Green south of Louisville.
And as has been studied by the University of Kentucky, there are karst formations in your state - a principal source of sinkhole formation.
I suggest contacting your building department to ask for some assistance. We can't say if the sinkhole risk to you is urgent or not based just on a text exchange.
I will add Kentucky karst references and information to the article above.
I add according to the U.K. experts at the Kentucky Geological Survey - U.K., www.uky.edu/KGS/gis/sinkpick.htm no sinkholes have been mapped in Daviess - your county in Kentucky.
So if investigation confirms that you and your neighbor are seeing actual sinkholes that could be important
(July 27, 2014) JoAnne Hahn said:
If there is a repaired sinkhole in an adjacent property is my house at greater risk?
We can't assess that sinkhole risk by text. You need an onsite spent. On one hand we now know your house is in an immediate sinkhole area. On the other we can't guess how unspecified work at a neighbor might reduce or increase your risk.
The risk to your house depends on the type of sinkhole and the general sinkhole risk in your area too.
(Aug 22, 2014) kim said:
I pulled a few pieces of slate out of the ground in my driveway, I noticed a quarter sized hole. It was weird, so I took the hose to see if it would fill up, but it didn't.
Water just kept running into the hole, and then I touched the rocks around the edges of the hole and they were just falling away. So I stopped.
I don't know if this is serious, but it was definitely starange, The hole was only about 10to 12 inches around, but the hole wouldn't fill up after a few mins. of putting water in it? What is that about?
The quarter sized hole was inside of the 10-12 inch hole where I pulled out the piece of slate.
Kim I can't know what you are seeing, but it MIGHT be an old cover over an old septic tank or drywall and so is indeed qyuite possibly very dangerous.
Or it might be a rodent hole - not dangerous unless you get bitten.
You want to rope off the area and keep people away until an excavator or other expert has figured out what's there. Nobody but a mouse is going to fall into a quarter-sized opening, but if there is a larger hidden problem you don't want someone falling into the opening.
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The frost heaving forces developed under a 1 ft. (30.5 cm) diameter steel plate were measured in the field throughout one winter. The steel plate was fixed at the ground surface with a rock-anchored reaction frame. heave gauges and thermocouples were installed at various depths to determine the position and temperature of the active heaving zone. The general trend was for the surface force to increase as the winter progressed. when the frost line approached the maximum depth the force was in excess of 30,000 lb (13,608 KG). Estimates of the heaving pressure at the frost line ranged from 7 to 12 psi (0.49 to 0.84 KG/cm) square during this period. The variation of surface heaving force was closely associated with weather conditions. Warming trends resulting in a temperature increase of the frozen layer caused the forces to decline.
Leda clay slopes in the Ottawa valley are vulnerable to catastrophic landslides. More than 250 landslides, historical and ancient, large and small, have been identified within 60 km of Ottawa. Some of these landslides caused deaths, injuries, and property damage, and their impact extended far beyond the site of the original failure. In spectacular flowslides, the sediment underlying large areas of flat land adjacent to unstable slopes liquefies. The debris may flow up to several kilometres, damming rivers and causing flooding, siltation, and water-quality problems or damaging infrastructure. Geologists and geotechnical engineers can identify potential landslide areas, and appropriate land-use zoning and protective engineering works can reduce the risk to property and people.
Deposits of Leda clay, a potentially unstable material, underlie extensive areas of the Ottawa-Gatineau region. Leda clay is composed of clay- and silt-sized particles of bedrock that were finely ground by glaciers and washed into the Champlain Sea. As the particles settled through the salty water, they were attracted to one another and formed loose clusters that fell to the seafloor. The resulting sediment had a loose but strong framework that was capable of retaining a large amount of water. Following the retreat of the sea, the salts that originally contributed to the bonding of the particles were slowly removed (leached) by fresh water filtering through the ground. If sufficiently disturbed, the leached Leda clay, a weak but water-rich sediment, may liquefy and become a 'quick clay'. Trigger disturbances include river erosion, increases in pore-water pressure (especially during periods of high rainfall or rapid snowmelt), earthquakes, and human activities such as excavation and construction.
After an initial failure removes the stiffer, weathered crust, the sensitive clay liquefies and collapses, flowing away from the scar. Failures continue in a domino-like fashion, rapidly eating back into the flat land lying behind the failed slope. The flowing mud may raft intact pieces of the stiffer surface material for great distances.