View Full Version : Sink hole question

12-15-2004, 12:53 PM
I got a call from one of my customers yesterday that a porton of his lawn was sinking in. About an 18 foot by 15 foot area.The section in question in now about 2 to 2 1/2 feet sunk (possibly a little more) below the rest of the lawn.This was not something that happend overnight but has been slowy sinking for about three years now possibly longer.

The customer has asked me to fill it in and i assume reseed(in the spring).

My question is should i wait till the warmer weather to fill in this hole?It is about 20F degrees today and the ground is pretty well frozen.I figured if i did it now, when the ground thaws it may sink a little more and i will have to bring in more topsoil.

I dont think there is any danger of it sinking too much more over the winter.Also it is not near any waterways and he doesnt have a septic tank.The area is on a slight slope im thinking the cause just may be some poor grading.

12-15-2004, 04:45 PM
You may want to bring in a mini ex and dig down through the sunken area. I am thinking natural spring or old terra cotta. While you are at it, see about addressing the drainage / grading issue at the same time.

Carolina Cutter
12-15-2004, 04:46 PM
Natural spring or septic tank maybe....if its a septic tank he has problems.....

12-15-2004, 05:26 PM
Natural spring or septic tank maybe....if its a septic tank he has problems.....

Septic was the first thing that came to mind. Get problem diagnosed first.

12-15-2004, 05:27 PM
Looks like i may have no choice but to wait, we might have a pretty heafty snow storm coming up.

I will have to talk to him more and find out when this "hole" started hes away on a business trip right now. Its not really a hole just a sunken area. I can still drive my ztr mower over it without any problems. I almost positive there is no septic tank.But it must be sinking for a reason.

12-15-2004, 05:35 PM
There didn't happen to be a BIG tree there at one time? Possible Decay?

12-15-2004, 05:52 PM
Tree is the first thing I thought of also. Definately ask some questions to determine the most likely cause before deciding on a plan to fix it.

12-15-2004, 06:40 PM
I think you should wait till spring or longer you could put dirt in the hole but i think you should dig down a little and see what the reason is. why i would wait is the dirt will not compact good in the hole. by spring you will have a sloppy mess and you will most likely do it all over again there is to much moister in the dirt that is frozen. trust me it will be a mess just wait my friend wait until spring when the dirt is dry

12-15-2004, 08:57 PM
in this area when homes are being built and trees taken out, in order to get rid of the stumps, contractors dig deep holes away from foundation and bury the stumps in there. over time the stumps break down and the depression gets deeper and deeper. i actually have 2 neighbors right next door to each other that have these 2 depressions at the end of the lawn that are like 2 ft deep and growing.

Jay Ray
12-15-2004, 11:56 PM
Heard of a case where a drywall contractor buried scrap gypsum in a pit, covered over, then sold. New owner filled it twice at about 1 foot of sink, that solved it.

12-16-2004, 12:26 AM
is it a true sinkhole? or is is a depresson from some other reason? that seems to be the question.

I say fill the hole ASAP. over fill it if you think you should.

the reason being that the depression acts as a conduit for rainfall to further weaken the soil structure IF it is a real sinkhole.

such an anomaly is known as a Karst Feature. Karst features are not at all anomalous here.


12-16-2004, 01:00 PM
I dont think its a sink hole, more of a depresson its has been around since i first started mowing this account about three years ago.This past summer it seemed to get worse, so finally he decided he wants to do something with it now that its 20 degrees with a snow storm on the way.