The Filter Backwash Recycling Rule, or FBBR, is a state regulation that requires any public water system to use a direct filtration treatment process to recycle filter backwash water. The FBBR became effective on March 26, 2002, for systems serving 10,000 or more people, and on April 27, 2002, for systems serving less than 10,000 people.

Filter Backwash Water is any wastewater that results from the initial filtration or polishing of treated water.

There are exceptions to the FBBR where wastewater recycling is allowed under certain conditions.

When the water system collects and treats wastewater from backwashing its filters, it must disinfect that effluent to inactivate any harmful organisms found in it. This wastewater recycling equipment should be designed according to a "treatment train" standard.

The EPA has set limits for these organisms:

Total coliforms - less than 1 colony per 100 milliliters

Fecal coliform - 0 colonies per 100 milliliters

E. coli - 0 colonies per 100 milliliters

The treatment methods allowed to disinfect effluent are the same types of disinfection techniques permitted for drinking water. They include ozonation, ultraviolet light, chlorination, or chlorine dioxide. The effluent recycling must meet the same regulations governing existing water treatment plants.

If a wastewater recycling system is not disinfected in accordance with EPA regulations, it will be considered an illegal discharge of pollutants under the Clean Water Act. If the wastewater recycling system breaks down or is shut down for any reason, the system must not allow wastewater to bypass or re-use equipment that was once used for this process without backwashing. The FBBR also stipulates that any wastewater recycling system under construction prior to March 26, 2002 can operate until completed and approved by the Department if it has a start date of March 26, 2002 or later.

The Filter Backwash Recycling Rule (FBRR) requires any public water system to use a direct filtration treatment process to recycle filter backwash water.