We have decovered a lage sink hole in lower end of front yard?? Who do we call for help? Could it be a underground spring? 6-12 ft deep


Who do we call for help? Sink hole in front yard??

I had some experience with sinkholes on State Highway property.
We had a geologist on the state staff we could get expert opinions from. If you are in a large urban area or county, you might start with their Public Works Dept. but they might not have any good recommendations. You could contact a consulting engineer firm but that will probably get expensive. If there are no utilities exposed, I would probably just fill it with some porous material like crushed stone. It was very likely caused by water traveling below the surface and a porous fill will allow the water to flow.
The state filled the holes with a flowable fill concrete mix but that gets expensive also.

What area do you live in. We have lots of sink holes in Florida caused by water being overused and pumped out of The Florida Aquifer. If there's as lot of development in your area expect more sink holes. Tom