Background

The city of Somerton provides water and wastewater services to all its residents. These services are provided 24 hours a day except when maintenance requires temporary shutoff of water service.

Raw water is supplied by three wells located within the city and drawn from an aquifer shared with the Cocopah Tribe and many private residences in the area. The city also has a 750 acre-feet allotment of Colorado River water that is currently not being used because of
prohibitive treatment and conveyance costs. The water treatment facilities consist of two parallel treatment plants with a combined capacity of 3.0 million gallons per day (mgd).

The city’s water distribution system consists of 2- to 14-inch asbestos cement pipes and 6- to 12-inch polyvinyl chloride (PVC) pipes with cast iron fittings, which vary in age and condition. Most of the water mains in the central part of the city are comprised of 4- and 6-inch cement pipes. These mains were primarily designed and constructed to provide
residential water service with only a very limited capacity for fire protection. Moreover, large sections of the system must be taken out of service during maintenance of fire hydrants for lack of isolation valves.

The existing cement pipes are old, deteriorating and undersized by
today’s standards. Although the quality of drinking water has not yet
been affected by the pipes, continued deterioration will compromise their
integrity and pose a serious health and safety risk for the community.

Description

The proposed project entails replacing and rehabilitating about 35
percent of the city’s water distribution system. Specific system
improvements include:

• replacing 42,670 feet of old undersized water mains
• installing 236 valves
• replacing 111 fire hydrants
• replacing 822 water meters

Benefits

Upgrading the waterlines will reduce system failures, maintenance requirements and costs, as well as potential health risks for users of the old deteriorating lines. In addition, improved water pressure will increase fire safety.