The primary goal of the Public Health Drinking Water Program is to prevent communicable disease and illness associated with drinking water from small public and individual private water systems. Public Health - Seattle & King County has regulatory oversight for small public water systems (Group Bs) serving 2-9 connections and individual private wells under WAC 246-291 and King County Board of Health Title 12 & 13. The Washington State Department of Health regulates the larger public water systems with ten or more connections, and or water systems serving 25 or more people for 60 or more days under WAC 246-290.

Public Health - Seattle & King County program goal is to provide Group B operators and individual private well owners with education information and technical resources to allow them to operate their water systems in a safe and efficient manner. Public Health - Seattle & King County performs a variety of activities to carry out its public health role:

• For individual private well systems serving one residence, the well location is reviewed, and the well installation must meet the Washington State Department of Ecology standards (WAC 173-160) for construction. New and replacement individual wells must be tested for water quality (coliform bacteria, arsenic, and nitrate). Additionally, Public Health staff answer questions on water quality issues, how to disinfect water systems, protection of well source from surface activities, etc.
  
  
• Small public water systems (Group Bs) must meet requirements for location, source adequacy, system design and construction, initial testing and on-going monitoring and maintenance.
  
  
• Other Activities: complaint investigation, routine inspections of existing systems, and special investigations in conjunction with other state and local agencies. Likewise, Public health staff assist water purveyors with contaminated sample issues, wellhead protection, explanation of purveyor duties with new operators, etc.