IN ALL OF the stories about the failures that occurred in the D.C. Water and Sewer Authority's monitoring of lead in the water supply, not much has been said about the agency's board of directors, where WASA's powers are vested. More attention should be paid. Six of the board's 11 principals represent the District and are responsible for handling matters that affect only D.C. ratepayers. As the special investigation of WASA by former U.S. deputy attorney general Eric H. Holder Jr. of Covington & Burling discovered, the board's oversight of WASA operations needs significant strengthening. Because of looming board vacancies, Mayor Anthony A. Williams, who appoints members with the advice and consent of the D.C. Council, has an opportunity to improve the caliber of board representation.

The board's shortcomings with respect to communication and governance are well documented. Mr. Holder's investigation found:

* Board members were provided with little information regarding WASA's lead monitoring efforts and its response to those efforts.

* Until The Post reported on the issue in January, board members were unaware that a large percentage of the results of sampling taken in conjunction with the lead service line replacement program had exceeded the regulatory lead action level.

* Board members did not have enough experience regarding the technical aspects of WASA's work to ask questions that might have drawn such information out of WASA executives earlier.

The report recommends the appointment of board members with pertinent technical expertise to assist in asking probing questions of WASA staff, including a member with an engineering background and a public health professional. WASA board Chairman Glenn S. Gerstell has already asked Mr. Williams to make such appointments and we hope the mayor will act accordingly and expeditiously.

Service on the board is part-time and most members have full-time employment. The terms of three D.C. members -- Michael V. Hodge, Lucy B. Murray and F. Alexis H. Roberson -- have already expired, and the terms of David J. Bardin and Mr. Gerstell expire next month. Mr. Gerstell stepped in and performed admirably when WASA's management proved not up to the job of communicating effectively with other agencies and the public about lead issues. He and Mr. Bardin have amply fulfilled their fiduciary obligations and warrant reappointment. Their presence is also necessary to oversee implementation of several key recommendations for improvements made by the Holder report.

It now falls to Mr. Williams to do his part by passing on the chance to reward political friends and instead fill board vacancies with nominees experienced in regulatory and water quality issues. The WASA board's ability to govern and the public interest hang in the balance.