I had a leak in my main water line at the Meter, a broken pvc pipe at the meter connection. Since we fixed the leak we had sand coming out of the faucets and toilets in the house. We cleaned out the faucet lines and repaired the toilet. I am left with a problem with the sprinkler system leaking. If I turn off the sprinkler valve then the meter stops turning. I started to try to flush out the line through a valve after the anti siphon device, no luck. I took off one of the sprinkler heads on one zone and let the water flush out. Still has a leak. Sand must be stuck in the lines or the valves. What do you think? Any easy way to clean it out and stop the leak? Thanks, Tony