It isn’t just your imagination — the D.C. metro area’s underground water pipe system is in fact busting more often than Elliott Gould. This morning’s WaPo has the details on the record-setting rates at which Montgomery and Prince George’s counties’ water pipes have leaked and broken down in the past month. In may in those two counties, 42 water pipes have broken, including the two water main breaks yesterday that left 2,200 residents in Bethesda…