Transmission Main – Larger Diameter mains tha bring water from the Water Plant to the city. Usually 16″ to 48″ in diameter.

Distribution System – Smaller pipes that move the water around the city. Usually 4″ to 12″ in Diameter.

Mainline Valve – The valves that regulate the flow of water through the mains.

Mainline Valve Box – 6″ diameter lid to access the valves. Sometimes seen in roads and tree lawns.

Service Line – The water line that feeds the home or business from the main. Usually copper.

Curb Stop – The valve that opens and shuts off the water supply to the home or business. The lid is usually 3″ in diameter and located in the treelawn or driveway apron.

Meter Valve- The first valve within the home that controls the flow of water in the home or business.