Marshall Municipal Utilities

Backflow Protection

A cross-connection is any temporary or permanent connection between a public drinking water system and any source containing nonpotable water or other substances. An example is the piping between a public water system and an auxiliary water system, cooling system, or irrigation system. Backflow is the undesirable reversal of flow of nonpotable water or other substances through a cross-connection and into the piping of a public water system. Backflow devices are installed to protect against a backflow occurrence.

MMU currently maintains certification records on all known backflow devices. Owners are notified by letter when their backflow device(s) is due for inspection and a record is kept when the device has been certified. All backflow devices must be tested by a state certified tester once a year.

Backflow DNR regulation, 10 CSR 60-11.010, requires that water suppliers take several steps in preventing backflow contamination of the water system. These include:

1. Remove meters or otherwise sever service to a customer causing a cross connection, to a customer refusing to correct any violation of the backflow regulation, or if ordered to do so by a local government authority or DNR;
2. Retain records; and
3. Track annual inspections of class I and class II backflow prevention devices and notify the customer with the device, any appropriate local government authority, and DNR of any failure to test a device annually.

The City of Marshall has a backflow prevention ordinance (Section 15 of Ord. #5909, amended by Ord. #7248).