Office of Drinking Water Quality

Public Drinking Water Information

Sanitary Survey Program

In addition to monitoring water quality, DWQ visits each Public Water System at least once every three years (Community systems) or five years (all others), to:

• Assure potability of the water supply through proper operation of the water system, and
• Assist in identifying and correcting deficiencies.

Groundwater systems (wells): To make sure that the wellhead itself is not threatened with contamination, our staff does a detailed inventory of all activities and land uses within the Inner Protective Radius, or IPR.  This is:

• 200 ft. radius around a bedrock well, or 
• 400 ft. radius around a gravel well. 

We look for things like:

• Septic systems,
• Other waste disposal,
• Hazardous materials stored or used  (paint, fuel, etc.),
• Storm water runoff, vehicle parking or repair. 

Surface Water Reservoirs: The survey team inspects the treatment plant and intake, and drives through the watershed to look for threats to water quality.

We look for things like:

• Large-scale development projects,
• Disturbed shoreline,
• Significant natural or human-caused erosion,
• Storm water runoff problems. 

The survey team produces a schematic diagram of treatment, storage and distribution systems, and looks for possible hazardous situations in the entire operation, such as:

• Cross-connections and backflow prevention,
• Proper maintenance and record keeping for all system components,
• Electrical hazards, confined spaces, and properly maintained plumbing.