INTRODUCTION
A cross-connection is defined by the American Water Works Association (AWWA) as “any connection or structural arrangement between a public or a consumer’s potable water system and any non-potable source or system through which backflow may occur.” Backflow, literally a reversal in the normal direction of flow within a water system, is what turns a cross-connection into a health hazard. Consequently, either cross-connections or the change of back flow must be eliminated to prevent these “Unseen hazards” from degrading the high quality of water that water purveyors strive to maintain.
The purpose of a cross-connection control program is to prevent waterborne diseases and contaminants from entering the distribution system and thus the water we drink. More exactly, the program is intended to prevent delivered water – water that has passed onto consumers – from re-entering the public distribution system and being subsequently delivered back to other consumers. The program aims to protect the Chester Metropolitan District’s water system and its consumers from those water-using establishments which could possibly harm the quality and safety of the community water supply through backflow and/or cross connection.
OBJECTIVES
The objectives of the Chester Metropolitan District’s Cross-Connection Control Program are as follows:
- To protect the public water supply from the possibility of contamination by isolating within its consumers’ private water systems, contaminants or pollutants which could, under adverse conditions, back flow through uncontrolled cross-connections into the public water system.
- To eliminate or control existing cross-connections actual or potential, between the consumer’s in-plant potable water system(s) plumbing fixtures, and industrial piping systems.
- To provide a continuing inspection program of cross-connection control which will systematically arid effectively control all actual or potential cross-connections which may be installed in the future.
POLICY
- No person shall install, permit to be installed or maintain any cross-connection between a public water supply, sewer, or waste line from any· container of liquids unless an approved backflow prevention device is installed between the public water supply and the source of contamination.
- Should the connection be between two approved public water supplies, common gate or check valves may be used provided this has the approval of both suppliers of water and the Department. (low Hazard)
- Should the connection be between an approved public water supply and to a service or other water supply not hazardous to health but not meeting the standards of the approved public water supply and not cross-connected within its system with a potentially dangerous water or liquid, any approved double check valve assembly shall be used. (Medium Hazard)
- Should the connection be between an approved public water supply and to a service or other water supply which has or may have any material in the water dangerous to health, or connected to any material dangerous to health that is or may be handled under pressure, or subject to negative pressure, protection shall be by air gap separation. An approved reduced pressure principal backflow prevention device may be substituted for an air gap, provided this alternative is acceptable to the supplier of water and the Department.
- The type of backflow preventer and degree of protection will be decided by the Chester Metropolitan District.
- All approved water systems interconnected to the Chester Metropolitan District shall have a common gate valve and/or check valve between the systems.
- All new residential 3/4″ and 1″ services will have a residential dual check valve installed at the water meter.
- There will be no connection made between the meter and device. The residential dual check valve will be installed by the Chester Metropolitan District with the cost of installation included in the tap fee.
- All low hazard customers shall have an approved double check valve assembly on the customer’s side of the meter. The customer shall own and maintain the double check valve,
excluding residential customers. - All medium hazard customers should have an approved double check valve assembly installed on the customer’s side of the meter. the customer shall own and maintain the DCVA valve assembly.
- All high hazard customers shall have an approved reduced pressure backflow prevention device on the customer’s side of the meter. The customer shall own and maintain the RPBP
assembly. - The cost of providing and installing any cross-connection control devices shall be paid for by the customer.
- The Chester Metropolitan District will maintain a current listing of all double check valve assemblies and RPBP device locations.
- The customer shall provide an annual inspection of each DCVA and RPBP device by a certified tester and submit the results of said test to the Chester Metropolitan District. For service connections that are considered by the District to pose an extremely high hazard, semi-annual or quarterly inspections and test may be required.
- The Chester Metropolitan District reserves the right to random inspections of any device. Should faulty or malfunctioning devices be observed, the owner shall make all necessary repairs within thirty (30) days of written notice.
- Should an owner fail to provide a certified test within thirty (30) days after notice, the Chester Metropolitan District will discontinue service ten (10) days after written notice from the General Manager of the Chester Metropolitan District.
- When existing water services are enlarged or replaced, the ~service will be considered to be a NEW SERVICE and the appropriate backflow prevention device will be installed using the criteria listed for NEW SERVICES.
- Facilities on existing services where cross connections are suspected will be inspected on a priority basis. When cross connections are found, the customer will be notified in writing to remove the cross connection or install the proper backflow prevention device within a period of time specified by the General Manager of the Chester Metropolitan District. Failure to remove the cross connection or install the proper backflow prevention device may result in discontinuation of water service.
- All presently installed backflow prevention devices which are not listed on the SCDHEC lis t of approved devices but were approved devices for the purposes described herein at the time of their installation and which have been properly maintained, shall be allowed to remain in service so long as in the opinion of the inspector they will satisfactorily protect the water system. Whenever the existing device is moved from the present location or requires more than minimum maintenance, or when the General Manager of the Chester Metropolitan District finds that continued use constitutes a hazard to health, the unit shall be replaced by an approved backflow prevention device.
ENFORCEMENT
Compliance with the Backflow Prevention Program is a condition of service for all customers and compliance is mandatory for continued service.
Failure of a customer to comply with the District’s installation, maintenance, or testing requirements will result in discontinuation of service ten (10) days after written notice from the General Manager of the Chester Metropolitan District.
ADMINISTRATIVE COST
A fee of $12.00 per test will be charged to customers requiring backflow prevention equipment monitoring. The fee will cover the administrative cost of monitoring and database management. The fee is required to submit test results.