Dirty water pumps?

The pumps available from B+Q and such places are ideal for that, around £37 for the smaller one, which filters out anything over 7mm or so - it pumps up sandy water with no problem.. They come in different powers/sizes, I needed one to empty a large hole in my garden when the mains pipe split. (Stupidly, I dug down to see where the pipe was damaged, and because the ground around the pipe was disturbed when i dug, the hole, by then, around 3 feet deep and round, just filled up with water in less than 5 minutes.) The pump emptied it in around 2 minutes, then kept the bottom of the hole dry enough for me to dig deeeper down to get good access to the pipe, and allow me to do a temp. repair until the water board could get round to replace the pipe. Alan.