The production and delivery of safe potable water at the lowest reasonable cost is the object of greatest importance to the North Wales Water Authority. When water of superior quality has been produced and put into the distribution system precautions must be taken to be certain that it is not contaminated from other sources. Since 1986, the Authority has taken on the development and operational functions of a Backflow Prevention and Cross-Connection Control Program in order to ensure that our distribution system is in compliance with the Safe Drinking Water Act. Under these requirements the Authority has the primary responsibility for protecting the public water supply from the backflow of substances that could endanger public health or physically damage the distribution system.
The term "backflow" refers to the condition when water flows in the opposite, or reverse, of the intended direction within a piping system. This reversal of flow could allow water that is compromised with other liquids, gasses or contaminated substances to enter the potable water system. Backflow can be achieved by either backpressure or backsiphonage. Cross-connections are the physical connections or arrangements between the drinking water supply and a piping system containing water or substances of unknown or questionable quality.
The probability of contamination to the public water system originating from a single facility seems remote, but considering the multitude of individual plumbing and fire systems throughout the Authority's distribution area, the probability is great and increases daily. The Authority's Backflow Prevention and Cross-Connection Control Program is referred to as a 'containment program' and is designed to contain, or isolate, water contamination within the plumbing or fire system where it originated. The backflow prevention device that must be installed on each service line allows water to flow into the facility, but will not allow water to return to the distribution system.
The Authority will determine the "degree of hazard" of each commercial or industrial facility by an evaluation of the conditions and activities within the premises. The "degree of hazard" is subject to change. Where an actual or potential impairment of water quality does not create a hazard to public health but does adversely and unreasonably affect the aesthetic qualities, an approved double-check backflow prevention assembly is required. Where an actual or potential impairment of water quality creates a hazard to public health through poisoning or through the spread of disease, an approved reduced-pressure backflow prevention assembly is required. Backflow prevention devices required by this program are the responsibility of the customer to purchase, install, and maintain. Contact the Authority for additional information regarding specific applications and device requirements.
The North Wales Water Authority's Backflow Prevention and Cross-Connection Control Program does not address internal protection requirements of individual plumbing systems. It is recommended that customers contact plumbing professionals with backflow prevention and cross-connection experience to ensure plumbing systems comply with all current codes.