THE GOVERNING BODY of the agency that provides drinking water and sewage service to 1.6 million customers in Montgomery and Prince George's counties is laboring under a stunning misperception. The commissioners of the Washington Suburban Sanitary Commission seem to believe that their main task is to engage in political shenanigans, paralyze major public works contracts and turn their infrequent public meetings into spectacles of dysfunction. In fact their mission is to ensure the businesslike operations of an important agency that manages a $659 million budget, employs 1,500 people and fulfills a key role in safeguarding public health. If the WSSC commissioners can't grasp that truth, they should be replaced or the commission restructured -- and quickly.

Since February the WSSC board has been embroiled in a half-hidden political tussle, apparently aggravated by Prince George's County Executive Jack B. Johnson. First came an abortive attempt by four of the six commissioners to fire the WSSC's general manager, John R. Griffin, and his deputy, for reasons that remain obscure. When that failed, owing to a technicality, the commissioners went into a snit, canceling meetings, bickering among themselves and delaying the approval of major contracts to build and maintain crucial water mains, sewage pipes, water filtration plants and wastewater pumping stations. Freezing the contracts, which range in value from $750,000 to $10 million, was especially irresponsible; in several cases, it could mean missing the summer construction season, driving up costs for customers and raising the risks of water and sewer main breaks this winter.

On Thursday, the board descended to a new low. Meeting for the first time in a month, and facing a room full of contractors awaiting decisions on delayed contracts, the commissioners squabbled over scheduling and adjourned after four minutes. Contractors, some of whom had driven hundreds of miles to attend the meeting, were irate; the WSSC's professional staff was aghast.

The power behind the WSSC board resides with Mr. Johnson and his Montgomery County counterpart, Douglas M. Duncan, each of whom appoints three members of the board. Mr. Duncan, with his eye on a run for governor in 2006, is keeping the agency and its problems at arm's length. Mr. Johnson's involvement is more intimate. It is unclear whether he instigated the turmoil -- as some WSSC staff members believe -- but he has exacerbated it by pushing his former campaign manager, Henry T. Arrington, to become the agency's interim general manager. That follows Mr. Johnson's pattern of using the WSSC as a dumping ground for his political allies and campaign contributors. Maryland elected officials have correctly opposed Mr. Arrington's appointment as one that would further politicize the agency.

The WSSC has a paradoxical history spanning several decades. On the one hand, it has functioned too frequently as a sinkhole of political patronage and shady contracting scams. On the other, it has reliably provided high-quality drinking water and sewage service to two large and increasingly urban counties. For years it has been possible to tut-tut the scams and take the service for granted, thanks to the efficiency of its professional staff. But given the havoc that the agency's commissioners have been wreaking, suburban customers and the state, which created the WSSC in the first place, may no longer be able to enjoy the luxury of forbearance. The board's hijinks are increasingly a threat to public health.