First thing to do is pump out the water so you can see down in it, or use something long to find out how deep it goes.
I have something like that on my property and it is a valve well, only the depth of a 5 gal. bucket that covers two water line valves, the lid keeps it from filling up with debris.
It is very possible that is what it is, or it might be a R. suggests.
It is unlikely it is a well, those usually have a Plastic outer pipe (thick walled) with a metal pipe inside that and usually the only cap is on the metal pipe, which is the actual well pipe.
I don't think it's for dog poop. It doesn't smell and there are no marks on the sides of the cylinder. After I cut the grass, I'll try to dig a little bit of it up to see if I can get a better idea of what it is. I'll also get a long stick to see how deep it is. What is a valve well?
Mignon Dietrich wrote:I don't think it's for dog poop. It doesn't smell and there are no marks on the sides of the cylinder. After I cut the grass, I'll try to dig a little bit of it up to see if I can get a better idea of what it is. I'll also get a long stick to see how deep it is. What is a valve well?
A valve well is a hole in the ground so valves don't have to be on risers for access. There are several different types for purchase, usually with a green lid and a black plastic "well portion with areas you can cut out for the pipes to run inside for valve attachment.
On our property we used standard 5 gal buckets with lids for this purpose.
This link has photos of different shapes available valve wells
I would be tempted to stick a stick in it to see how deep it is. The stick might tell you if it has something in it like electrical.
We have several pipes in the ground that look similar to that. Some are associated to our septic system, some are associated as a cleanout for plumbing, and one is connected to the septic to dump our RV. I wouldn't expect any of them to smell.
It might be filled with either rainwater or your water table. I would do research before trying to pump it out.
Are you buying the property or renting it? A call to the former owner would tell you what it is.
If it is related to a septic system there would be records on file with the county. Do you have a Annual Maintenance Service Contract? If so, your service contractor might know what it is. Aerobic and Drip systems require a maintenance contract.
Since you show "DFW" I assume you are in Texas. There are strict laws regarding property less than 10 acres.