Overflows/Backflow Prevention

Interceptors Plugging, Overloading, or Backflow 

 The District serves notice that its interceptors and main lines may plug, flow full, or may surcharge, and flooding of the collection system may occur.  The customer is put on notice that their service line shall be designed, constructed, connected, operated and maintained at the sole risk of the customer.

The District Building Sewer Connection Requirements must be followed when designing, connecting or repairing lateral sewer service lines which are connected to the District’s main line sewers.  For a situation where a backflow from District main sewers is possible, Section 8 of the Requirements must be followed.

Section 8. Sewers Below Grade

Sewer line piping serving fixtures which have a flood level rim located below the elevation of the next upstream manhole cover shall be protected from backflow of sewage by the installation of an approved type backflow valve available at most plumbing supply outlets.

Backwater valves shall have cast iron, PVC, or brass bodies, non-corrosive bearings, seats and self aligning discs, and shall be constructed as to insure a positive mechanical seal and to remain closed, except when discharging wastes. Such valves shall remain sufficiently open during periods of low flows to avoid screening of solids and shall not restrict capacities or cause excessive turbulence during peak loads.

Valve access covers shall be bolted type with gasket and each valve shall bear the manufacturer’s name cast into body and cover. Alternate devices may be approved for a specific installation.

Additionally, sewer line piping serving fixtures located below the crown level of the sewer main shall discharge into an approved watertight sump or tank, so located as to receive the sewage by gravity. Sewage from the sump shall be lifted and pumped into the sewer main under pressure.

It is suggested that if the homeowner has any concerns of backflow or overflow from the main line, a backflow device should be installed.

Note: All repairs or modifications to the customer’s service line are subject to the issuance of a permit and inspection by District personnel.