Hayward Sand Filter Winterization issue

I winterized my inground pool yesterday and had an issue with my Hayward sand filter. I did what I normally do to winterize the filter tank but when I removed the bottom drain plug to drain the water in the tank, not only did the water drain from the tank but so did a steady stream of sand! Appears all the sand from within the tank flowed out. Never had this happen before? Not overly concerned for the closing but upon opening , what should I expect to fix. I was going to change out the sand anyway next season. I am assuming I have broken laterals. Had no problems with sand in the pool this past season. Any input from the experts here as to what happened. Thanks Pete

The water drain in many sand filters is sort of a mini-lateral - closed tube with small slots that keep sand out but allow water through.

When these break open, the drain allows BOTH sand and water through, instead of just sand. Usually, you have to remove 100% of the sand (some still left inside, I promise!) and then replace the drain fixture. There's a fair chance you'll have to replace a couple of filter laterals at the same time. If you don't fix it this fall, I'd plan to work on it a month before your pool is ready to open, so you have time to order and receive any bits and pieces you find you need.

Thank you for the diagnosis! I intend to open the pool alot earlier next year and your help will definitely point me in the right direction to troubleshoot this annoying problem. Pete

Glad it helped!