We have a sinkhole on the land that the library is on. The prevalence of sinkholes is possibly why the family that owned the land donated it to the city rather than selling it. There is a really cool area just past the parking lot that serves as a sort of drain for the area. Heavy rains pour into it, and then sink down. There is a lot of limestone in this section, and trees grow up around it and protect it from (some) erosion.

But then there are other areas away from it that are developing subsidence. There are small sinkholes developing. I’ve taken pictures of one area over time, and just now thought to put a few of them here. I’ll try to keep an eye on it and add more to this story as it develops.

The first time I noticed the extra sinkhole, they had put a barricade around it. They roped it off to prevent people from accidentally falling into it while they got an engineer to figure out what to do.

This is what was decided.

They put a huge tarp in it, and drop boulders into it. The idea was not only to plug up the hole but to prevent more dirt from washing away. They had at least twenty boulders to put in it. It was an all-day event. I’m glad saw this going on because it was pretty cool.

This lasted about a year. Then they had to add more rocks on top of the area, as it had sunk down. They are smaller than the first batch. Here’s the “after” shot.

That was about six months ago. That too has started to subside.