Sand after pool closed.

[Zegster]

I had sand coming into my pool this summer and hired a pool company to replace my lateral and spider thingy at the bottom in the middle of the summer. I didn't have problems with sand getting into the pool after and it stayed clear. Well I hired a company to close my pool, they emptied all the water onto my drive way. I noticed sand on my driveway. Not a ton but about a few hand fulls. I don't know if they backwashed all my water out of my pool or not, but I'm guessing they did, since there was a bunch of sand. I checked the sand filter by tapping on it and it still has about halfway up with sand, which what I read is normal. So it wasn't alot that got dumped out.

Do you just think this is from replacing the lateral and putting in new sand. Also from backwashing. I'm curious how sand stays in when backwashing. I can't do much about it now that my pool is closed though.

 

[JVTrain]

Sand should stay put during filtration and backwashing. It could be that some of the sand was smaller than the recommended grain size and this came out when doing extensive backwashing. If they were doing a drain to lower the water level to remove a lot of volume, I should say that they should have suctioned to Waste rather than Backwash to bypass the sand and reduce the chances of that happening.