CSO 50/50 Sewer Backflow Program
The City of Manchester Department of Public Works administers a 50/50 reimbursement program through the Environmental Protection Division. The EPD is responsible for the sewer collection system and the wastewater treatment plant.
The City’s sewer collection system is made up of two different types of piping systems, separate systems that convey only wastewater and combined systems that carry both wastewater and stormwater to the treatment plant. This program is only available to properties within combined sewer portions of the City.
What is the difference between wastewater and stormwater?
Wastewater is generally composed of liquids and solids including raw sewage from toilets and drainage from sinks, bathtubs, showers, washing machines and dishwashers. Wastewater is piped to the City’s wastewater treatment facility
Stormwater is rain or snowmelt that runs off of impervious areas like streets, sidewalks, parking lots and roofs. In many cases, catch basins or storm drains collect this runoff and convey it to the nearest waterbody. In areas with a combined system it is collected in the City’s wastewater system and conveyed to the treatment plant.
Combined Sewer Systems
Approximately 50% of the city has a combined sewer system. A combined sewer system is a single pipe designed to collect both wastewater and stormwater and convey it to the City’s wastewater treatment facility (WWTF). During normal conditions, flows are delivered to and treated at the WWTF. During heavy rain events, when flows surge due to increased stormwater runoff, the combined sewer system can become overloaded, resulting in combined sewer overflows (CSOs) of untreated sewage into the nearest water body. During severe rain events, flows can also backup into residential homes and businesses. The city is actively working to separate combined systems and reduce CSO incidents.
To determine if your property is located in an applicable portion of the City, please click on the link below:
If you meet that requirement and are interested in applying:
About the Program
The CSO 50/50 Sewer Backflow Program was established to assist property owners located within combined sewer areas with the costs to install new sewer backflow prevention devices to protect their buildings from sewer backups as a result of combined sewer systems through a reimbursement process.
This program is conditional upon funding and approval by the Highway Commission. This program will not be retroactive and therefore reimbursement cannot be requested for backflow devices installed before initiation of this program.
Backflow preventers are one of the best methods to prevent wastewater entering a building through sewer services during large storm events, which can create health hazards and cause property damage. Reimbursement will be for improvements that include installation of an approved sewer backflow prevention device on the property either internally or externally.
Sewer Services and Backflow Prevention
What is a sewer service and who is responsible?
A sewer service or “private service lateral” is the connection pipe from the interior plumbing in your building to the public sanitary sewer pipe or “sewer main” located in the city street or easement. In the City of Manchester, property owners are responsible for maintaining their sewer service from the building to the sewer main.
What is a Backflow Preventer?
A backflow preventer is a plumbing valve or device that allows wastewater to leave the building during normal flows, but closes and prevents wastewater and/or stormwater from flowing back into the sewer service from the sewer main. Generally composed of a valve and small flap, these prevention devices will open to allow wastewater to exit the building and close during a backup event to try and prevent sewage from flowing backwards into the building. Backflow prevention devices are the most efficient and cost-effective tool to help minimize backup of municipal sewage into basements.
How Does a Backflow Prevention Device Work?
During normal operation, a small flap inside the backflow preventer is generally open, allowing wastewater to exit your property. If wastewater starts to flow backwards into your building, the flap is then closed, thus helping to prevent wastewater from backing up into your building. Once the backflow subsides, the flap will open and allow wastewater to resume flowing out of your building and into the sewer system.
It is important to note that with some devices, if water is used (shower or toilet flush) in the building while the flap is closed, water cannot escape and can fill interior pipes or in worst cases, can prematurely open the flap and then allow wastewater to enter the building.
Where Are Backflow Prevention Devices Installed?
Backflow preventers are typically installed on your property along the length of pipe between your building and the street. Alternatively, some devices can be installed in your basement. Once properly installed by a licensed plumber, your backflow prevention device can last for many years with proper maintenance and care. This typically includes an annual cleaning and inspection.
The Work
Construction work to be reimbursed under the 50/50 Program must be performed by a licensed plumber (internal and external installations) or a certified pipe layer (external installations only). Since this is a reimbursement program, it is up to the property owner to hire a contractor to complete the work.
All work done through the 50/50 Program must conform to the City's Standard Specifications and Local Building Codes, and obtain necessary local permits. A Building Permit through the Planning & Community Development Department will be required for internal installations and a Sewer Repair or Connection Permit through DPW will be required for external installation.
The property owner is responsible for the layout of the desired work, obtaining bid proposals/cost estimates, hiring a qualified contractor, and the inspection of work throughout the construction process. It is important that this information is well documented and provided to the City at project completion for processing of reimbursement requests.
Ultimately, the selection and vetting of a qualified contractor is up to the property owner and the City cannot be held liable for faulty workmanship or contracting challenges. It is important for the property owner to select a contractor carefully. Because of these important requirements, consider having the layout, bid proposals, and work inspected by a professional independent from the City for conformance to the City's Standard Specifications and Local Building Codes.
Program Policies & Considerations
Financial contribution from the City to property owners for backflow devices is only available through the 50/50 Program.
This program is only available for the construction or reconstruction of backflow devices on properties exclusively within the combined portions of the City of Manchester.
To determine if your property is located in an applicable portion of the City, please click on the link below:
CSO 50/50 Sewer Backflow Area
Potential reimbursed costs shall not exceed $5,000 for each installation. Reimbursable costs include purchase and installation of a backflow prevention device and associated plumbing.
Depending on the plumbing configuration of the property, the device can be installed either internally (in the basement or below a slab) or externally under lawn areas, walkways or driveways and fully within the property bounds. Installation of backflow devices within the City ROW will not be allowed.
For internal installations, costs for demolition of existing sewer service components, floor removal and in-kind restoration within extents of trench work can be eligible. For external installations, excavation, backfill and in-kind restoration (e.g. placement of loam/seed or surface patching) within the trench extents can be eligible. Additional scope items and work outside trench limits may not be eligible. Work will follow the City of Manchester Standard Specifications for sewer and local plumbing codes.
This is a popular program and receives consideration from the Public Works Director and Highway Commission each year. Funds are available on a first come first served basis.
How to Apply
Complete an Online Application or print, complete and mail an Application Form for backflow prevention device reimbursement. Follow the detailed instructions included with the application form.
Determining the Cost & Reimbursement Amounts
Once the cost of the proposed construction has been determined, it should be forwarded to the City by the property owner along with the completed application. The cost proposal must outline the total cost and include a detailed breakdown of items so the City can confirm the allowable reimbursed portion of the cost up to a maximum of $5,000. The cost proposal should be current within 6 months of the application date.
As noted above, this program is based on first come, first served basis and once available reimbursement funds are expended within the fiscal year, the property owner may have to wait for reimbursement approval, as funds become available the following year. The City will notify the property owner when those funds are available in advance, so work scheduling can begin.
Completing and Documenting the Work
Once application and reimbursement amounts are approved by the Highway Commission, the work can begin. As noted under The Work section above, the property owner will be required to hire and coordinate work completion by a licensed plumber or certified pipe layer depending on external or internal installations. Once the application is approved, work can be completed at any time during the year. Property owners should keep in mind that external installations may be weather dependent and that should be taken into account when planning or applying for reimbursement.
Upon work completion, it is important that the property owner provide the proper documentation to ensure reimbursement from the City, which includes the following:
- Time stamped photos of the completed work;
- Plumber or contractor invoices;
- Proof of payment;
Upon receipt of this documentation by the City, the approved reimbursement amount will be mailed to the property owner within 30 days.
Selecting a Device
Another consideration for the property owner is to select a proper and adequate backflow device and whether additional storage is desired. With most backflow devices, once the valve is activated, water usage may have to be minimized to prevent flooding of the wastewater that cannot drain. Providing storage can help minimize these impacts. Some types of backflow devices include:
- Sewer Check Valves are the least expensive and the most common type of backflow preventer that holds back most of the backflow for a short period of time. It requires regular maintenance and cleaning to prevent clogging.
- Automatic Floodgate Valves hold back all of the backflow for a longer period of time. They have a gate that closes automatically when it senses a reversal of flow and opens when the flow returns to normal. They typically also have an alarm that alerts you when it closes.
- Manual Sewer Gate Valves must be opened and closed by hand. They hold back all of the backflow for as long as you keep it closed, however require you to be present and aware of the situation to activate it.
It is best to consult with a professional to determine the best sewer backflow preventer for your needs considering location, pressure rating, type and maintenance requirements. With proper maintenance and care, a backflow prevention device can last for several years. Typical maintenance includes annual inspection and cleaning.