A storm drain check valve, also known as a backwater preventer or inline valve, is an important part of the City’s storm water management infrastructure. It allows seawater to flow through the outfall pipe and not back up into the sewer line, helping to mitigate coastal flooding.
When a check valve fails or does not seal, it can allow backflow into the sewer system or other waterways, which can lead to costly damage and pollution. It is also an indicator that the system is in need of repair or replacement.
It is common in many residential areas for roof runoff to be connected to the municipal sewer piping through storm drain check valve or sumps. This can cause significant problems for the sewage treatment plant during storms as it adds excess wastewater volume that can overwhelm the plant and cause it to overflow.
These discharges can also contaminate clean water supplies. Therefore, check valves are used to prevent sewage from flowing back into the public’s drinking water supply and potentially harming the health of the community.
The valves can be installed in a number of different locations including under the foundation of a house, above the main sewer line and on the sewer lateral outside of a house. It is best to consult a licensed plumber for installation and to make sure it is compliant with the code.
Backwater Preventer for Floor Drains
To install a backflow preventer on a floor drain, lower it into the pipe until the float comes up with the strainer or cover and then tighten the screws. This will create a seal in the drain pipe.
There are several different types of backwater sanitary valves to choose from depending on the size and application of the drainage line. The most common is the mainline full-port backwater valve, which is installed in a hole cut in the foundation above the sewer line or on the sewer lateral outside the house.
Other options include a ball check valve or an electronic control backwater valve, which is similar to a duckbill check valve but is electronically controlled and automatically shuts off when it detects backflow. These devices are easy to maintain and are not mechanically operated.
Inline check valves are a great option for the stormwater system because they open with little head pressure and are out of the flow path. They can be adapted to fit various pipe diameters and are a cost-effective way to keep water flowing in the right direction and away from the home or business.
They are available in a variety of materials to suit any application and are available with threaded or solvent weld connections.
Agri Drain manufactures a line of check valves that help prevent sewer backflow. This company is based in San Antonio, Texas and specializes in designing and manufacturing check valves for sanitary, waste and stormwater systems.
The City of Charleston recently installed 22 inline check valves to help mitigate the impact of tidal flooding from stormwater pipes. These valves are an economical way to improve the safety and reliability of the stormwater infrastructure in areas that are susceptible to tidal inundation.