The District’s governing power is vested in its 37 members of the Board of Trustees. One trustee is appointed by each of the 36 cities and the County Board of Supervisors appoints one to represent unincorporated areas of Los Angeles County. To be appointed, the member must reside in and be a resident voter of the representative city (or county for county member) in the District. Board member duties and responsibilities include setting policy, establishing the budget, approving expenditures, and retaining legal counsel. The trustees serve a minimum of two or four-year terms without compensation, but do receive an in lieu travel expense of $100 for attending each regularly scheduled board meeting.

The regularly scheduled board meetings are held on the second Thursday of each month, starting at 7:00 p.m., at District headquarters in Santa Fe Springs. All meetings are open to the public.