The Washington Suburban Sanitary Commission wants to raise Prince George's and Montgomery County residents' water bills 7.5 percent, or an average of $4.86 per month, beginning in July.

The increase is the result of a $265.9 million, or 22.3 percent, increase in the agency's budget for fiscal 2013. The vast majority of the hike — $230.9 million — would go toward a proposed $796.9 million construction budget.

WSSC listed several construction projects that need to be done in the coming fiscal year, citing a deteriorating infrastructure.

"Water main break rates continue to increase (December 2010 was a record high month with 647 breaks or leaks) and major failures may continue to occur unless we re-invest in this critical infrastructure," the agency wrote in its request.

Reasons for the $34.9 million increase in the agency's $661.1 million operating budget include a 2-percent cost-of-living increase and merit increases for all employees. However, the primary reason for the increase is WSSC's debt obligations, which will climb if the construction budget increases. Debt payments are expected to exceed last year's by $25.4 million.

WSSC will host two public hearings on its budget proposal, on Feb. 1 and 2 at 7:30 p.m. The first hearing will be at 1400 McCormick Drive in Largo in room 308, and the second will be at 100 Maryland Ave. in Rockville in the Seventh Floor Council Hearing Room.