§ 51-4. Protection required.

A. 

Each service connection from a public water system for supplying water to premises having an auxiliary water supply shall be protected against backflow of water from the premises into the public water system, unless the auxiliary water supply is approved as an additional source by the water purveyor and is satisfactory to the public health agency having jurisdiction with regard to quality and safety.

B. 

Each service connection from a public water system for supplying water to premises on which any substance is handled under pressure in such fashion as to permit entry into the water system shall be protected against backflow of the water from the premises into the public system. This shall include the handling of process waters and waters originating from the public water supply system which may have been subject to deterioration in sanitary or chemical quality.

C. 

Each service connection from a public water system for supplying water to premises on which a substance of unusually toxic concentration or danger to health is handled in liquid form, even though it is not under pressure, shall be protected against backflow of the water from the premises into the public system, e.g., plating factories, premises using cyanide and hospitals. This is not intended to apply to normal household installations.

D. 

Backflow prevention devices shall be installed on the service connection to any premises that have internal cross-connections, unless such cross-connections are abated to the satisfaction of the water purveyor. It shall be the responsibility of the water user to provide and maintain these protective devices, and each one must be of a type acceptable to the State Health Department.