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Water: Microbial & Disinfection Byproducts Rules

Fact Sheet On The Final Filter Backwash Recycling Rule


What are we announcing?
EPA is finalizing a Filter Backwash Recycling Rule (FBRR) to address a statutory requirement of the 1996 Safe Drinking Water Act (SDWA) Amendments to promulgate a regulation which "governs" the recycling of filter backwash water within the treatment process of public water systems PWSs. The purpose of the FBRR is to require (PWSs) to review their recycle practices and, where appropriate, work with the state Primacy Agency to make any necessary changes to recycle practices that may compromise microbial control.

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Who does this rule apply to?
The FBRR applies to all public water systems that:

  • use surface water or ground water under the direct influence of surface water (GWUDI);
  • utilize direct or conventional filtration processes; and
  • recycle spent filter backwash water, sludge thickener supernatant, or liquids from dewatering processes.

What are the requirements of this final rule?
The FBRR requires that recycled filter backwash water, sludge thickener supernatant, and liquids from dewatering processes must be returned to a location such that all processes of a system's conventional or direct filtration including coagulation, flocculation, sedimentation (conventional filtration only) and filtration, are employed. Systems may apply to the state for approval to recycle at an alternate location.

The FBRR also requires that systems notify the state in writing that they practice recycle. When notifying the state, systems must also provide the following information:

  • A plant schematic showing the origin of all recycle flows, the hydraulic conveyance used to transport them, and the location where they are recycled back into the plant; and
  • Typical recycle flow in gallons per minute (gpm), highest observed plant flow experienced in the previous year (gpm), design flow for the treatment plant (gpm), and the state-approved operating capacity for the plant where the state has made such determinations; and

Finally, systems must collect and maintain the following information for review by the state, which may, after evaluating the information, require a system to modify their recycle location or recycle practices:

  • Copy of the recycle notification and information submitted to the state;
  • List of all recycle flows and the frequency with which they are returned;
  • Average and maximum backwash flow rate through the filters and the average and maximum duration of the filter backwash process in minutes; Typical filter run length and a written summary of how filter run length is determined (headloss, turbidity, time excetra);
  • The type of treatment provided for the recycle flow; and
  • Data on the physical dimensions of the equalization and/or treatment units, typical and maximum hydraulic loading rates, type of treatment chemicals used and average dose and frequency of use, and frequency at which solids are removed where such units are used.

How soon after publishing the final rule will the changes take effect?
Systems must submit the notify the state with the appropriate information no later than 30 months after promulgation of the rule. Systems must comply with the recycle return location requirements of the FBRR by 36 months following promulgation of the rule. If a system requires capital improvements to modify the location of their recycle return, they must complete all improvements no later than 60 months after promulgation of the rule.

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Why is this rule significant?
The practice of filter backwash recycling has not previously been addressed in drinking water rules promulgated by the Agency. Section 1412(b)(14) of the 1996 Amendments to the SDWA, required EPA to promulgate a regulation governing the recycling of filter backwash water within the treatment process of a public water system no later than four years after the date of the enactment of the SDWA Amendments of 1996 unless this type of recycling has been addressed by EPA's Enhanced Surface Water Treatment Rule prior to the deadline.

The FBRR addresses filter backwash water and 2 additional recycle streams of concern, i.e., sludge thickener supernatant and liquids from dewatering processes. The Agency believes that establishing such a regulation will improve performance at conventional and direct filtration plants by reducing the opportunity for recycle practices to adversely affect plant performance in a way that would allow microbes such as Cryptosporidium to pass through into finished drinking water.

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How will this regulation protect public health?
EPA has determined that the presence of microbiological contaminants is a health concern. If finished water supplies contain microbiological contaminants, illnesses and disease outbreaks may result. Of the 12 waterborne cryptosporidiosis outbreaks that have occurred at drinking water systems since 1984, three were linked to contaminated drinking water from water utilities where recycle practices were identified as a possible cause. The Milwaukee, Wisconsin outbreak alone was responsible for over 400,000 illnesses and 50 deaths.

The Surface Water Treatment Rule (SWTR) and Interim Enhanced Surface Water Treatment Rule (IESWTR) set enforceable drinking water treatment technique requirements to reduce the risk of waterborne microbiological disease including Cryptosporidium from surface water. Today's final rule provides further necessary protection of Cryptosporidium for system's that practice recycle.

Today's rule ensures that the 2-log Cryptosporidium removal requirement established in the IESWTR (63 FR 69478, December 16, 1998) and proposed in the Long Term 1 Enhanced Surface Water Treatment Rule (LT1ESWTR) (65 FR 19046, April 10, 2000) is not jeopardized by recycle practices. The rule requires (with some exceptions) that recycle be returned through the processes of a system's existing conventional or direct filtration (as defined in §141.2 of the CFR) that the Agency has recognized capable of achieving 2-log (99%) Cryptosporidium removal of recycle. Today's rule also ensures that systems and states will have the recycle flow information necessary to evaluate whether site-specific recycle practices may adversely affect the ability of systems to achieve 2-log Cryptosporidium removal. Surges of recycle flow returned to the treatment plant may adversely affect treatment systems by creating hydraulically overloaded conditions (when plants exceed design capacity or state-approved operating capacity) that can lower performance of individual units within a treatment plant resulting in lowered Cryptosporidium removal efficiency.

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How many people and how many systems will be affected by this rule?
The final FBRR is expected to apply 4,650 systems which serve nearly 35 million Americans. Fewer than 400 systems are expected to require capital improvements as a result of the rule.

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How much will this rule cost?
EPA estimates that the annualized cost of today's final rule will be $5.84 million. Capital costs associated with modifications to recycle locations at an estimated 371 systems represent $5.5 million. The recycle return provision of today's final rule accounts for 95% of total annualized costs. Public Water System expenditures for all provisions are greater than 99% ($5.8 million) of total annualized costs; state expenditures make up less than 1% ($0.07 million).

The mean annual cost per household is $0.20 and the total annual cost per household is less than $1.70 for 99% of the 31.4 million households potentially affected by today's final rule. The remaining 1% of households will experience a range of costs between $1.70 and approximately $100 per year. Only 321 of the 31.4 million households potentially affected by the FBRR (.00005%) are expected to incur costs of approximately $100 per year.

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What are the benefits of this rule?
The primary benefits of today's final rule come from reductions in the risk of illness from microbial pathogens in drinking water. In particular, FBRR focuses on reducing the risk associated with disinfection resistant pathogens, such as Cryptosporidium. Other disinfection-resistant pathogens may also be removed more efficiently due to implementation of these provisions. Exposure to other pathogenic protozoa, such as Giardia, or other waterborne bacterial or viral pathogens are likely to be reduced by the provisions of this rule as well. In addition to preventing illnesses, this rule is expected to have other non-health related benefits. These benefits result from avoiding non-health related costs associated with waterborne disease outbreaks.

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Is there funding associated with this rule?
Since 1996, the Drinking Water State Revolving Loan fund (DWSRF) has made over $4.4 billion available to states which they have used to provide loans to help water systems improve their infrastructure. Through December 31, 2000, states had made close to 1600 loans for more than $3.2 billion. Other federal funds for infrastructure financing are available through the Housing and Urban Development's Community Development Block Grant Program, and the Rural Utilities Service of the U.S. Department of Agriculture. EPA also provides program management funding to states that have primary enforcement responsibility for their drinking water programs through the Public Water Systems Supervision (PWSS) grants program.

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How did EPA consult with stakeholders?
The Agency worked with American Water Works Association (AWWA), the American Water Works Service Company (AWWSCo.), and Cincinnati Water Works to develop twelve issue papers on commonly generated recycle flows. EPA began outreach efforts to develop the FBRR in the summer of 1998. Two public stakeholder meetings, announced in the Federal Register, were held on July 22-23, 1998, in Lakewood, Colorado, and on March 3-4, 1999, in Dallas, Texas. In addition, EPA held several formal and informal meetings with stakeholders, trade associations, and environmental groups. Small entity representatives also contributed valuable input as part of the Small Business Regulatory Enforcement Fairness Act (SBREFA) panel process. The FBRR SBREFA panel was initiated in April of 1998 and officially convened in August of 1998. The panel's recommendations were incorporated into the FBRR. In early June 1999, EPA mailed an informal draft of the FBRR preamble to approximately 100 stakeholders who attended either of the public stakeholder meetings. Members of trade associations and the SBREFA panel also received the draft preamble. EPA receivedvaluable comments and stakeholder input from 15 state representatives, trade associations, environmental interest groups, and individual stakeholders. During the comment period for the FBRR, the Agency held a public meeting in Washington DC on April 14, 2000. Additionally, the proposed rule was either presented or discussed in nearly 50 meetings across the U.S. Finally, EPA requested stakeholder comments by mailing approximately 200 copies of the proposed rule to stakeholders requesting comment. EPA received 67 comments from a variety of stakeholders including states, municipalities, tribes, elected officials, consultants, trade groups, and private industry. These comments were reviewed and evaluated while developing the FBRR.

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Where can the public get more information about this final rule?
For general information on the FBRR, in addition to a link to the Federal Register notice of the final regulation or any of the technical factsheets and guidance can be found on EPA's website or can be obtained by contacting the Safe Drinking Water Hotline, at (800) 426-4791.

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