26 ELR 10296 | Environmental Law Reporter | copyright © 1996 | All rights reserved

Combined Sewer Overflows and Sanitary Sewer Overflows: EPA's Regulatory Approach and Policy Under the Federal Water Pollution Control Act

Kevin B. Smith

Editors' Summary: Combined sewer overflows and sanitary sewer overlows present unique problems for regulators. Although these problems were largely ignored until recently, EPA has finally begun to address the significant environmental and public health hazards these pollution sources pose. The author first provides a brief overview of the problems of combined and sanitary sewer overflows and the basis for their regulation under the FWPCA. He next discusses EPA's policy and guidance efforts to date, including the relevant documents' specific requirements and the concerns that shaped them. Finally, he presents some thoughts on the direction future regulaton of combined and sanitary sewer overflows should take.

Kevin B. Smith is an Assistant Regional Counsel in U.S. Environmental Protection Agency (EPA) Region 4's Office of Regional Counsel. Prior to his current position, Mr. Smith worked in the EPA Headquarters Office in Washington, D.C., and was involved in the development of several federal regulatory revisions under the Federal Water Pollution Control Act. He is a Senior Attorney in the area of water law, though his practice also includes hazardous wastes, toxics, safe drinking water, and underground storage tanks. Mr. Smith speaks frequently on environmental and water law issues and serves as an adjunct professor at the Emory University School of Law in Atlanta, Georgia, instructing in the areas of environmental law and water resources. Mr. Smith prepared this Article in his private capacity. No official support or endorsement by EPA or any other agency of the federal government is intended and should not be inferred.

[26 ELR 10296]

As our nation grows and our cities become increasingly crowded, the issue of sewerage system capacity and sewage treatment becomes more compelling, especially as it relates to the impact of sewage system discharges on our waterways.1 The growing instances of overflows from municipal systems into the nation's waters are of particular concern.2 These overflows can occur as discharges from separate sanitary, storm, or combined sewer outfalls. While such discharges are most prevalent during wet weather, inadequately designed, old, or neglected systems can also have discharges during dry weather. More important, these discharges often occur in areas where the discharge of untreated sewage can present high risks of human exposure, such as streets, private property, basements, and small streams. In addition to creating significant public health risks, these discharges can contribute to exceedances of water quality standards and can be indicative of deteriorated or otherwise inadequate municipal infrastructure.

While significant strides have been made in the two decades since the passage of the Federal Water Pollution Control Act (FWPCA) (now referred to as the Clean Water Act),3 the issue of sewer overflows still needs additional work. In fact, these underground flows of storm, industrial, and domestic wastewaters have often gone ignored, unnoticed, or forgotten.

Introduction to Combined Sewer Overflows

A combined sewer system is a publicly owned pipe system that conveys a combination of sanitary wastes (domestic, commercial, and industrial wastes) and stormwater runoff to a publicly owned treatment works (POTW). During dry weather, these systems convey only sanitary sewage to the local sewer treatment plant. During wet weather, these systems convey both sanitary wastes and stormwater. In periods of heavy or prolonged rainfall, however, these collection systems frequently convey more combined wastewater than the system or the POTW can accommodate. To prevent hydraulic overload at the POTW, combined sewers have relief outlets along the collection system and within the treatment works4 from which discharges of untreated wastes can occur. During rainfall, as the flow exceeds capacity, the stormwater and wastewaters in the system then flow directly into surface waterbodies such as lakes, rivers, estuaries, or coastal waters. Combined sewer overflows (CSOs) are the discharges of raw sanitary wastes and stormwater runoff into our nation's waters from those outlets.

[26 ELR 10297]

While today most U.S. cities have separate systems for stormwater runoff and sanitary wastewaters, combined sewer systems still exist in many communities—primarily in the Northeast and Great Lakes regions. In the United States, there are approximately 1,100 cities with combined sewer systems with as many as 15,000 CSO outlets, serving a population of 43 million people.5 In many cases, the cities with CSOs are those with sewer systems built before wastewater treatment was contemplated or regulated—when the assimilative capacity of the local receiving waterbodies was viewed as inexhaustible.

When it became apparent that this was not the case, communities began to build POTWs to treat sanitary sewage during dry weather. Now, as technology has increased, attention has turned to increased protection of our waterways through control of CSOs. The causes of CSOs are often site-specific. They include lack of maintenance and infrastructure deterioration, hydraulic loading during rainfall events, infiltration,6 and inflow7. The U.S. Environmental Protection Agency (EPA) estimates that CSOs could be a $ 41 billion dollar problem nationwide over the next 15 years.8

The need to correct the CSO problem is immediate and the cost warranted. A variety of environmental and public health problems can result from CSOs. The pollution discharge impacts include: (1) aesthetics—the presence of odor and floatable solids; (2) public health and safety concerns—overflows into streets, yards, and streams where there can be a high risk of human contact with toxics and microbial pathogens ranging from dysentery to hepatitis; (3) water pollution—high levels of solids, oil, grease, nutrients, and toxic pollutants such as industrial chemicals, pesticides, and metals; and (4) water quality impacts—reduced dissolved oxygen levels in receiving streams that impact on the survival of fish and other aquatic life. In addition, failure of communities to control CSOs properly in compliance with the FWPCA can leave them open to legal liabilities including government enforcement and citizen suits.

History of CSO Requirements and Controls

Like all point-source pollutant discharges, CSOs are covered under FWPCA § 301.9 Under FWPCA § 402, the national pollutant discharge elimination system (NPDES), EPA and authorized states may issue permits for the control of discharges from CSOs.10 These permits are intended to ensure that the CSO discharges meet technology-based11 and water quality-based12 requirements of the FWPCA.13

CSOs historically have not been a high priority for EPA and the states; rather, they often have been ignored. The publicity of CSO discharges into public parks and waterways, however, has caused EPA and the states to devote more resources to developing guidance and regulations for these point sources. EPA, states, and the public have begun to recognize the complex nature of CSOs and their control. Not only can CSOs exhibit extreme variability in their volume, frequency, and discharge characteristics, their impact on water quality can also be difficult to distinguish from the impact of other sources (e.g., stormwater and nonpoint sources) during wet weather. In addition, relatively few studies have documented the efficacy of CSO controls.

Nor has Congress adequately recognized the unique nature of CSOs.14 Thus, localities have had some concern that Congress and EPA might attempt to regulate CSOs in the same manner as other point-source discharges, which must meet the compliance deadlines set forth in the FWPCA. That would make the FWPCA's point-source effluent limitations, for which most of the compliance deadlines have already passed, applicable to CSOs immediately.15 It is argued that such regulation of CSOs without consideration of the possible need for time to implement new technology or compliance schedules could impose a significant hardship.

While the general public may view CSOs as part of a municipality's wastewater collection system, the FWPCA views them as independent point sources not subject to the [26 ELR 10298] secondary treatment requirements for POTWs.16 To date, however, EPA has not promulgated categorical technology-based guidelines for CSOs as it has for POTWs.17 Therefore, the applicable technology-based standards must be determined on a case-by-case basis using the permit writer's best professional judgment (BPJ).18 In addition, the permit writer must apply any appropriate water quality-based standards.19

Recent studies indicate that in many cities, CSOs are a major contributor to water quality degradation. CSOs are among the sources shown to be responsible for beach closings,20 and cause 6 percent of the limited shellfish harvest areas in the North and Middle Atlantic.21 These problems gave rise to a great need for the development of wet weather water quality-based standards guidance.

In an effort to address the challenges that CSOs presented, EPA published a National CSO Control Strategy (CSO Strategy) in September 1989.22 The CSO Strategy reaffirmed that CSOs are point sources subject to NPDES permit requirements and recommended that all CSOs be identified and categorized according to their condition. EPA intended the CSO Strategy to accomplish several things. First, the CSO Strategy emphasized that unpermitted CSO discharges were unlawful and must be issued a permit or eliminated. Second, it established objectives for the control of CSOs. Third, it called on the states to develop statewide permitting strategies designed to reduce pollutant discharges from CSOs. Finally, it promoted as minimum technology-based limits the proper operation of and regular maintenance programs for the sewer systems and the CSO points. In addition, it indicated that significant guidance would follow.

The established objectives for the control of CSOs were a major focus of the CSO Strategy. These stated objectives included ensuring that CSOs occur only as a result of wet weather, if at all; bringing all wet weather CSO discharge points into compliance with the FWPCA's technology- and water quality-based requirements; and minimizing impacts to water quality, aquatic biota, and human health.

EPA intended implementation of CSO control measures to take place at the state level, through EPA-approved state plans. The CSO Strategy noted that the state CSO strategies should be developed at the community and/or state level. It suggested that state plans should provide for identification and categorization of CSOs according to existing compliance with technology- and water quality-based standards, prioritization for permitting action, issuance of a permit (with any applicable schedule of compliance), and compliance monitoring.

While the 1989 CSO Strategy successfully focused increased attention on CSOs, EPA found that the CSO Strategy still did not address several key issues. These areas of concern included the site-specific nature of CSOs and their impacts; the need for flexible, cost-effective solutions; and consideration of the timing and costs of CSO controls. By mid-1991, it was clear that implementation of the 1989 CSO Strategy was not meeting EPA's goals. As a result, EPA convened a group under a modified regulation/negotiation process to develop a consensus product: a nationally consistent permitting policy for controlling CSOs. EPA involved representatives of key CSO stakeholders such as communities with CSOs, state officials, and environmental groups to assist in narrowing and clarifying the technical and economic issues.

Following public comment, and with the contribution of the negotiation effort, EPA issued a revised CSO Control Policy (CSO Policy) on April 19, 1994.23 EPA intended the CSO Policy to clarify expectations for municipalities, NPDES permitting agencies, and state authorities on water quality standards. In particular, the CSO Policy provides guidance for developing appropriate, site-specific NPDES permit requirements; provides flexibility to communities in determining appropriate ways to meet FWPCA § 101's objective;24 and allows a phased permitting approach with consideration of environmental impacts and a municipality's finances. The CSO Policy contains two key requirements: (1) immediate implementation and documentation of nine minimum technology-based controls based on site-specific needs; and (2) development of long-term CSO control plans.25

The nine minimum technology-based controls provide a base for the regulatory program. The nine minimum controls include requirements such as proper operation and regular maintenance programs for the sewer system and the CSO [26 ELR 10299] points, maximum use of the collection system for storage during rainfall, use of pollution-prevention programs that focus on contaminant reduction activities, and measures to ensure that the public receives adequate notification of CSO occurrences and impacts. In addition, CSO discharges during dry weather are prohibited. Selection and implementation of the actual control measures are to be based on site-specific considerations and the community's overall CSO control plan. Because the FWPCA requires immediate compliance with technology-based controls, BPJ requirements (including the nine minimum controls) are to be included in a permit or appropriate enforcement mechanism, with a compliance schedule, if necessary.

The second aspect of the revised policy is the development of long-term CSO control plans (control plans) to ensure ultimate compliance with the FWPCA. Communities are to develop and submit their control plans as soon as practicable, but generally no later than two years after the date of the permit revision, the § 308 information request, or the date established in an EPA or state order requiring the permittee to develop the control plan.26 The control plans should consider the site-specific nature of CSOs and evaluate the cost effectiveness of different options or strategies. In addition, the control plans should be designed to allow for effective expansion of the system and its development and should be coordinated with the state authority responsible for reviewing and revising state water quality-based standards (WQSs), to ensure the control plan provides for compliance with WQSs. Control plans should be especially proactive where the CSOs are causing serious water pollution and/or the minimum technology-based controls are insufficient to address the CSO problem.

Control plans have several objectives. The first is to characterize the CSOs and their impacts on water quality through monitoring and modeling of the combined sewer system (CSS). The intent of this requirement is to provide the municipality with the necessary information to meet the FWPCA's requirements. During this process, the community is to evaluate different alternatives, with the goals of attempting to eliminate or relocate all CSOs, giving special consideration and priority attention to environmentally sensitive areas, and providing for public participation.27

A second objective of control plans is to evaluate two alternative approaches to meeting WQSs. In addition to considering ways to reduce the CSO impacts on sensitive areas, the CSO plans are to address one of two overall targets: controls that are either "presumed" to meet or can be "demonstrated" to meet WQSs. A program may be presumed to provide adequate control to meet WQSs if: (1) no more than four overflows occur per year; (2) the CSS/POTW treats or captures at least 85 percent of the volume; or (3) the system effectively eliminates or removes the mass of the pollutants of concern.28 CSO flows that remain after implementing the nine minimum criteria and that satisfy the above criteria should then be treated with primary clarification29 and disinfection of the effluent.30

If a permittee's program is unable to meet the "presumptive" criteria, the permittee may still "demonstrate" that its selected control program will be adequate to meet the FWPCA water quality-based requirements. For a system to satisfy the requirements for this level of control, the permittee must demonstrate that: (1) the system is adequate to meet WQSs and protect designated uses; (2) all the CSOs remaining after implementation of the control plan will not preclude meeting WQSs; (3) the system will provide maximum pollution reduction reasonably attainable; and (4) it is designed to allow for cost-effective expansion.31

EPA recognized the expansive goals of the CSO Policy and provided some flexibility in the development and implementation of community control plans. The CSO Policy allows phased implementation of CSO control plans, to provide the maximum degree of beneficial environmental impact with consideration of the financial capability of a community. The policy suggests that municipalities should rely on a number of short- or long-term methods to abate the negative impacts of CSOs, including maximizing existing capabilities, stormwater and sanitary sewer separation, satellite treatment at CSO outfalls, and construction of and use of basins or tunnels to increased storage and treatment capacity.32

Finally, as noted above, CSOs are point sources subject to NPDES permitting requirements and enforcement actions. Thus, while the CSO Policy gives communities considerable flexibility, it lays out specific performance expectations that communities must meet. Under the CSO Policy, EPA and states must incorporate elements of the CSO Policy directly into NPDES permits and other enforcement mechanisms, particularly, the nine minimum technology-based controls. The CSO Policy specifies that additional water quality-based requirements should be established where applicable. As such, the CSO Policy established a uniform, nationally consistent approach to developing and issuing NPDES permits.33 Where communities [26 ELR 10300] fail to comply, the authorized permitting agency should take enforcement action.34 Currently, EPA's major enforcement targets are dry weather discharges and Phase I & Phase II permit requirements.35

EPA's experience with development of state CSO plans has been promising. As of January 1996, EPA had approved 29 of the 30 state control plans and had conditionally approved one. Twenty states had not submitted control plans because there were either no known CSOs or no problematic CSOs. In EPA's Region 4 (Southeast), all eight states are into Phase II permitting (drafting permits or other enforcement mechanisms with requirements for implementation of a long-term CSO plan), and currently there are only three states with CSOs—Georgia (50), Kentucky (206), and Tennessee (49).36 Georgia and Kentucky have submitted state CSO control plans. Tennessee has issued administrative orders and is working through the traditional permitting process.37 Of the six cities in Georgia with CSOs, two have constructed separated systems (Cedartown and Augusta). Atlanta, however, continues to be plagued with problems in upgrading its municipal system, and is currently under a consent order to address its CSOs.38

Introduction to Sanitary Sewer Overflows

Municipal separate sanitary sewer systems (SSSs) are designed to collect only domestic and industrial (i.e., sanitary) wastewater, with some allowances for groundwater infiltration, and transport the wastewater to the POTW. A sanitary sewer overflow (SSO) is a discharge from the SSS occurring before conveyance to the POTW. An SSO, thus, does not receive the necessary primary, secondary, or higher treatment.39 Unlike CSSs, SSSs are not built to accept stormwater and therefore are generally without "designed" relief outlets. Rather, SSOs occur from manholes, broken pipes, etc., and can occur during wet or dry weather.

The causes of SSOs are just as site-specific as CSOs. The common causes for SSOs include grease or debris blockages, bottlenecks in the system, undersized pipes, lack of maintenance, power failures, and vandalism. In addition, the situation may be exasperated by hydraulic loading during wet weather due to infiltration and inflow. Chronic SSOs are often symptomatic of infrastructure deterioration due to inadequate preventative maintenance programs, poorly performing or undersized pumps, insufficient system rehabilitation and replacement programs, or insufficient planning for new development. EPA estimates that in the United States there are approximately 18,000 municipal SSSs serving a population of 135 million, all of which can, under certain circumstances, experience overflows.40

Like CSOs, SSOs cause several types of concerns and problems for municipalities and the general public. SSOs present public health concerns because they contain pollutants including pathogenic microorganisms, suspended solids and floatables, oil, grease, nutrients, and toxic pollutants such as metals. SSOs can also jeopardize public safety; they can overflow into streets and yards and flood basements. SSOs also create legal liabilities, in that noncompliance with the FWPCA can leave a municipality open to federal and state enforcement, as well as citizen suits.

History of SSO Requirements and Controls

Like CSOs, SSOs are point-source discharges subject to FWPCA permitting requirements under FWPCA § 402.41 EPA has not, however, issued a formal guidance or policy addressing SSOs as it has for CSOs. EPA and the public are still grappling with the issue of how we should address SSOs.42 On the one hand, SSOs may be considered, by definition, unauthorized discharge points. Yet permits have been issued allowing these discharges.43 This raises the sticky question of whether EPA should provide for "allowable" discharges of raw or diluted raw sewage from usually undesigned outfall points.

A safer position would be to view discharges from SSOs as de facto unpermitted discharges that are prohibited under the [26 ELR 10301] FWPCA. Given that separate sewer systems can be designed for a definite or anticipated wastewater load, and that separate systems do not have to deal with the potential variability due to stormwater inflow, there should be no need to provide for intentional (i.e., permittable) outfall points from these systems.44 Currently, an EPA workgroup is evaluating the issues and the legal status of these discharges.45

Traditionally, EPA and authorized NPDES states have addressed SSO problems under the FWPCA's construction grants program and by bringing enforcement actions to address severe SSO problems.46 Generally, such enforcement actions have been directed at the elimination of SSOs, and have not envisioned the authorization of such discharges.47 In 1994, the Association of Metropolitan Sewerage Agencies and other interested stakeholders asked EPA to develop a national policy to address SSOs. Municipalities had expressed frustration with the lack of clear, realistic objectives and the lack of consistency in addressing SSOs. Some municipalities were unwilling to report SSOs or commit to large collection system repair projects until additional regulatory certainty or guidance was provided.

In response, EPA convened an SSO Federal Advisory Subcommittee in late 1994 to assist in identifying and evaluating SSO issues.48 Membership on the committee included municipal sewer officials, environmental groups, and state, county, and EPA representatives. EPA anticipated that the dialogue would result in better understanding of the problem nationally and in development of guidance advising NPDES-authorized states and EPA Regions on how to better protect the public and the environment from SSOs. The SSO Advisory Subcommittee considered many topics, including quantifying the nationwide scope of the SSO problem; deciding what steps should be taken to ensure adequate identification and reporting of SSOs; and identifying interim steps that could be taken to minimize health and environmental risks from SSOs before final resolution of SSO problems.

After hearing the preliminary comments and concerns of the SSO Advisory Committee, EPA developed and, on August 7, 1995, distributed a draft enforcement strategy for addressing discharges from SSOs.49 The draft strategy announced a method for establishing priorities for the regulatory response to control SSOs. While focusing on enforcement priorities, the draft strategy attempts to clarify several outstanding issues concerning SSOs, including definitions, legal considerations, and a priority scheme to address this national problem. It is thus a first step in providing SSO control guidance to municipalities as well as to EPA Regions and the states.

The draft strategy begins by providing a working definition for SSO discharges, and then provides six principles that EPA and states should consider as they set priorities for addressing SSO discharge violations.50 These basic principles recommend focusing time and energy on the most pressing problems first,such as discharges that contribute to water quality or public health problems and discharges occurring in areas with high public use or access. The draft strategy suggests that these actions then should be integrated with, or closely followed by, long-term preventative measures such as addressing dry weather discharges and operation and maintenance needs. The draft strategy recognizes that where compliance schedules are used, they should take into account the financial capabilities of and the normal planning, design, and construction practices that the specific municipality uses.

The draft strategy also provides a priority scheme and suggested responses for correcting SSOs. The priority scheme again focuses on and promotes addressing dry weather discharges first. In order of priority, it recommends addressing: (1) operational problems such as poor treatment response to changes in influent flow and proper communication between field crews and management; (2) maintenance problems such as pump failure and sewer cleaning; and (3) capacity-related problems. This would be followed by addressing wet weather operation, maintenance, and capacity problems. Finally, the draft strategy provides guidance to regional and state personnel responsible for working with (or taking enforcement action against) municipalities that seek to prevent violations and comply with FWPCA requirements.

Currently, the Federal SSO Advisory Subcommittee is moving toward development and agreement on a national [26 ELR 10302] strategy for controlling SSOs. Development of a final policy is expected in early 1996.

FWPCA Reauthorization—Congressional Debate

As noted earlier, Congress had not formally recognized the unique nature of CSOs until recently. Recent efforts by both Houses of Congress, however, have placed emphasis on addressing CSOs and SSOs.

House bill, H.R. 961, which the House passed in May 1995,51 specifically requires compliance with the April 1994 CSO Policy and would require EPA to develop an SSO policy within two years of enactment.52 It would amend FWPCA § 40253 to add a new section "(s) Combined Sewer Overflows," which would provide that "each permit issued pursuant to this section for a discharge from a combined storm and sewer shall conform with the combined sewer overflow control policy signed by the Administrator on April 11, 1995." The new section would authorize the permitting authority to give a discharger up to 15 years to comply with CSO permit limits. Additionally, it would allow for extension of the compliance schedule date at the sole discretion of the permitting authority if the permitting authority determines that the owner or operator is not economically capable of complying by the original date and the owner or operator demonstrates to the satisfaction of EPA or the states reasonable further progress toward compliance with a long-term control plan under the CSO Policy. Finally, the new section would require any consent decree or court order entered by a U.S. district court or any administrative order issued by EPA before enactment of the bill to be modified to extend any deadlines or compliance schedules to conform to the new law.54

In addition to requiring EPA to enact an SSO control policy, H.R. 961 also requires each permit issued pursuant to FWPCA § 402 to conform with the control policy; authorizes the permitting agency to issue permits for discharges from municipal sanitary sewers due to stormwater inflows or infiltration; allows for compliance schedules of up to 15 years; and provides provisions similar to those for CSOs for extensions of compliance schedules and modification of consent decrees, court orders, or administrative orders.55

The bipartisan 1994 Senate FWPCA reauthorization bill, S. 1114, also incorporated the 1994 CSO Policy by reference. However, it is still under consideration by the Senate Environment and Public Works Committee.

EPA has viewed these actions as indicative of congressional support for its efforts. The December 13, 1995, Senate Environment and Public Works Committee hearing on FWPCA reauthorization has given rise to a belief that momentum as been restored. At this time, however, FWPCA reauthorization may be a low congressional priority compared to reauthorization of Superfund and the Safe Drinking Water Act.56

In contrast to this move toward recognition of the CSO/SSO problems and EPA's consensus approach to addressing them is Congress' attempt to restrict further federal action in this area through the fiscal year 1996 budgetary process. In particular, the original House funding bill, as proposed, not only reduced EPA's general operating budget, but included a rider that prohibited expenditure of funds by EPA for enforcement of restrictions or compliance schedules for CSOs or SSOs.57

The Clinton Administration Position

The Clinton Administration views the CSO Policy as a way to strengthen environmental protection while providing communities with the flexibility they need to pursue workable, cost-effective solutions. The Administration's confidence in and commitment to the CSO Policy is so strong that the President's Clean Water Initiative recommended its adoption as part of the pending FWPCA reauthorization actions.58


While significant strides have been made to protect the waters of the nation, the issues raised and the pollution problems that CSOs and SSOs present still need additional work. The CSO Policy provides a good framework, though the complex and variable nature of CSOs and their control has prevented quick movement toward the policy/guidance and permit/implementation stage. These overflows still affect many waterways.

The draft SSO enforcement strategy also is a good step; however, it only begins to address the issues raised by SSOs. It provides a recommended priority scheme for characterizing and correcting SSO discharges while emphasizing the dominant theme of addressing and preventing dry weather discharges as soon as possible. Given that the various EPA Regions and states currently address SSOs differently, the next move should be toward a national policy similar to that for CSOs. It should be EPA's guiding SSO goal to provide national consistency in the way SSOs are addressed. The Federal SSO Advisory Subcommittee's move toward development and agreement on a national strategy for controlling SSOs is commendable. The fact that different interests are represented also is laudable; however, that some of the interested parties question the need for a binding national policy may affect the timing by which any national strategy is issued.

Specific congressional recognition of the human health and environmental concerns that CSOs and SSOs present also is necessary. Incorporation of the CSO Policy into, and recognition of the need for an SSO policy in, the FWPCA would help clarify uncertainty regarding the future regulatory framework for management of these discharges. Congressional support is warranted and such action in a newly reauthorized law would be a major improvement to the existing statute. But the reauthorization efforts should not be viewed as an opportunity to relax any existing statutory mandates or requirements.

[26 ELR 10303]

Finally, additional education of the public and regulated community is essential. The impact of illegal connections and the human health and environmental cost of deteriorating systems needs to be recognized. CSO/SSO policy and regulatory requirements should not be viewed as another "unfunded mandate" or hollow cost to the public. Protecting ourselves from harmful environmental activities is as important as protecting ourselves from street crime. These actions are as essential as roads or education for our children if we are to provide a better quality of life for future generations.

1. Prominent examples in recent public light include the Atlanta system's impact on the Chattahoochee River, the Boston system's impact on the Boston Harbor, and Chicago's impact on Lake Michigan. Each case involves old systems designed to allow combined wastewater to overflow to local waters during storms. As residential and industrial development grew, the systems became overtaxed and the discharges of raw sewage and untreated stormwater began having severe adverse impacts on the receiving water bodies—these discharges were in the millions or even billions of gallons per year.

2. States cite pollution from wet weather discharges as the leading cause of water quality impairment. U.S. EPA, NATIONAL WATER QUALITY INVENTORY: 1992 REPORT TO CONGRESS, EPA 841-F-94-002 (1994) (available from the ELR Document Service, ELR Order No. AD-1173).

3. 33 U.S.C. §§ 1251-1387, ELR STAT. FWPCA §§ 101-607.

4. Discharges from the system within the property boundary of the POTW, however, are considered "bypasses." See infra note 44.


6. EPA has defined "infiltration" to include water that enters the sewerage system from the ground through such means as defective pipes, pipe joints, connections, or manholes. See 40 C.F.R. § 35.905 (1995).

7. EPA has defined "inflow" to include water from sources such as roof drains, cellar drains, yard drains, foundation drains, drains from springs and swampy areas, manhole covers, cross connections between storm sewers and sanitary sewers, catch basins, cooling towers, storm drains, surface runoff, or street wash waters. See id. § 35.905.

8. CSO CONTROL POLICY, supra note 5.

9. 33 U.S.C. § 1311, ELR STAT. FWPCA § 301.

10. Id. § 1342, ELR STAT. FWPCA § 302; Decision of the General Counsel, No. 48 (June 30, 1976) (EPA determination that discharges from combined sewer overflows are discharges from "point sources" and must comply with FWPCA requirements. However, CSOs are not "publicly owned treatment works," within the meaning of the NPDES regulations. See also Decision of the General Counsel, No. 49 (June 30, 1976).

11. "Technology-based standards" are control methods required for specific categories of dischargers. 33 U.S.C. § 1311(b), ELR STAT. FWPCA § 301. For example, the nationwide requirement for POTWs is "secondary treatment." Secondary treatment requires removal of 85 percent of solids and oxygen demanding pollutants; a 30-day average discharge of no more than 30 mg/l for Biological Oxygen Demand (BOD[5]) and Total Suspended Solids (TSS); and a 7-day average discharge of no more than 45 mg/l and a pH of 6.0 to 9.0. 40 C.F.R. § 133.102 (1995).

12. "Water quality-based standards" require treatment sufficient to meet state standards in the receiving water body to protect the use designated for that water, such as trout fishing or drinking. 33 U.S.C. §§ 1311(b)(1)(c), 1313, ELR STAT. FWPCA §§ 301, 303.

13. See also 40 C.F.R. § 122.45(a) (1995).

14. Recent efforts by both Houses of Congress, however, have placed some emphasis on addressing CSOs. House bill, H.R. 961, which the House passed in May 1995, requires compliance with the April 1994 CSO Policy and development of an SSO policy. (But it also would allow the permitting authority to give a discharger up to 15 years to comply with SSO permit limits.) Senate bill, S. 1114, a bipartisan FWPCA reauthorization bill, also incorporated the CSO Policy by reference.

15. The FWPCA provides that EPA-promulgated effluent limitations (e.g., best available technology) and state-issued water quality standards must be met by specified deadlines, most of which have already passed. See 33 U.S.C. §§ 1311, 1313, ELR STAT. FWPCA §§ 301, 303. EPA may issue compliance schedules for meeting standards applicable to a permittee only in limited circumstances. See 40 C.F.R. § 122.47 (Schedules of Compliance). Any schedule of compliance must require compliance as soon as possible, but no later than the applicable statutory deadline under the FWPCA. Thus, because the statutory deadlines have passed, EPA can not issue compliance schedules for CSOs, and they would be required to meet the effluent limitations immediately.

16. EPA has maintained that CSOs are not part of the definition of "treatment works" within the meaning of the FWPCA. A CSO is designed to be a device to discharge wastewater, not for the storage, treatment, or reclamation of sanitary wastes. Montgomery Envtl. Coalition v. Costle, 646 F.2d 568, 11 ELR 20211 (D.C. Cir. 1980). See also Decision of the General Counsel, No. 48 (June 30, 1976); definition of POTW at 40 C.F.R. § 122.2 (1995).

17. EPA probably will not be promulgating any categorical standards in the near future due to the uniqueness of any toxic pollutants in each source. Because of this discharge variability, permits covering CSOs often incorporate narrative (BMPs) rather than numeric technology-based standards. For example, the current CSO controls basically require communities to (1) fully utilize the existing capacity of wastewater collection and treatment systems through changes in operational practices; (2) prevent pollutants from entering the combined sewers; and (3) install simple devices to remove solids and floatable materials from the CSO discharge (e.g., install bar screens at CSO locations). In some cases, the minimum controls may be adequate to achieve state water quality standards. Combined Sewer Overflow Control Policy, 59 Fed. Reg. 18688, 18691 (Apr. 19, 1994).

18. Such BPJ determinations are often not easy and generally must take into account such factors as the proposed cost of the CSO control, the intermittent and dilute nature of the CSO discharges, the large rate of the discharge, and the often remote locations of CSO outfalls.

19. See, e.g., Northwest Envtl. Advocates v. City of Portland, 56 F.3d 979, 25 ELR 21250 (9th Cir. 1995), vacating Northwest Envtl. Advocates v. City of Portland, 11 F.3d, 24 ELR 20238 (9th Cir. 1993). That case held that a citizen group was entitled to enforce both discharge permit limitations and conditions. Compliance with water quality standards was a permit condition, even though CSOs were not specifically listed in the permit and the permit lacked effluent limitations for CSOs.

20. Kimberely Barton & Deare Fuller, TESTING THE WATERS V: POLITICS AND POLLUTION AT U.S. BEACHES (1995).

21. The percentage increases to 37 percent when other wet weather discharges are included. NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION, 1990 NATIONAL SHELLFISH REGISTER OF CLASSIFIED ESTUARINE WATERS app. D (1991).

22. Combined Sewer Overflow Control Strategy, 54 Fed. Reg. 37370 (Sept. 8, 1989).

23. Combined Sewer Overflow Control Policy, supra note 17, at 18688.

24. FWPCA § 101 provides that "the objective of this chapter is to restore and maintain the chemical, physical, and biological integrity of the Nation's waters…. (1) it is the national goal that the discharge of pollutants into navigable waters be eliminated…." 33 U.S.C. § 1251(a), ELR STAT. FWPCA § 101(a).

25. Combined Sewer Overflow Control Policy, supra note 17, at 18691.

26. Id. at 18688, 18698.

27. Id. at 18692.

28. Pollutants of concern are those pollutants identified as causing water quality impairment through the sewer system characterization, monitoring, and modeling project.

29. Removal of floatables and settleable solids with subsequent disposal.

30. Combined Sewer Overflow Control Policy, supra note 17, at 18692-93.

31. Id. at 18693.

32. EPA has published several guidances for municipalities and permitting agencies faced with addressing CSO issues. These include: U.S. EPA, COMBINED SEWER OVERFLOWS: GUIDANCE FOR FUNDING OPTIONS, EPA 832/B-95-007 (1995) (available from the ELR Document Service, ELR Order No. AD-504); U.S. EPA, COMBINED SEWER OVERFLOWS: GUIDANCE FOR LONG-TERM CONTROL PLANS, EPA 832/B-95-002 (1995) (available from the ELR Document Service, ELR Order No. AD-423); and U.S. EPA, COMBINED SEWER OVERFLOWS: SCREENING AND RANKING GUIDANCE, EPA 832/B-95004 (1995).

Several methods are being considered or used in the EPA Region 4 (Southeast) states: interceptor bar screens to remove solids and disinfection of the first flush from the CSO in Atlanta, Georgia; expanded interceptor system to capture the first flush and treat at the POTW in Albany, Georgia; construction of a 3.5 million gallon storage/transport facility to control certain CSO discharges in Chattanooga, Tennessee; and separation of the CSS into separate stormwater and sanitary sewer systems in Bristol, Tennessee and Sanford, Florida.

33. Existing state CSO strategies should now be consistent with the revised CSO Policy. At a minimum, they should provide for "Phase I" NPDES permits requiring implementation of technology-based requirements and submission of municipality's long-term plan. In some cases, "Phase II" NPDES permits, which require implementation of a long-term plan, may be required.

34. FWPCA §§ 308, 309, and 504 provide broad enforcement authority to address CSOs. 33 U.S.C. §§ 1318, 1319, 1364, ELR STAT. FWPCA §§ 308, 309, 504. Action may be initiated against any person who discharges without a permit or who violates any NPDES permit requirement. Finally, FWPCA § 402(h) provides EPA and approved states, with the authority to seek civil judicial action to stop further wastewater connections to a POTW where the NPDES permit for that facility is being violated. Id. § 1342, ELR STAT. FWPCA § 402.

35. Combined Sewer Overflow Control Policy, supra note 17, at 18696-97. See, e.g., United States v. City of Niagara Falls, 706 F. Supp. 1053 (W.D.N.Y. 1989). City of Niagara Falls held that a discharge of untreated dry weather flow from CSO constituted a violation of the FWPCA, and that the appropriate remedy was permanent injunction requiring immediate rediversion of the maximum portion of flow back to the POTW that could be accomplished without significant modification to City's system.

36. Florida had a single city, Sanford (near Orlando) with CSOs. Sanford has now separated its CSS into independent sewer and stormwater systems.

37. EPA approved Georgia's control plan in April 1990 and approved Kentucky's control plan in January 1991. Tennessee sent notification that it would not need a CSO Control Plan because the state had issued administrative orders to all municipalities with CSOs. On the expiration of the current permits, Tennessee intends to follow the administrative orders with reissued permits including appropriate CSO requirements.

38. The Georgia Legislature set a deadline of December 1993 for all Atlanta CSOs to attain compliance. (At the time, one of the most aggressive goals in the nation.) The state has issued permits and administrative orders to the city to insure compliance; however, Atlanta has been paying penalties since November 1992 for failure to meet requirements in the permits and orders. Based on Atlanta's studies, it will need $ 107 million to construct the four treatment plants to address CSOs. Several local citizen groups are currently seeking to have Atlanta (and Georgia) take further action or to get a court order to enforce against the city for its alleged laxity in addressing the CSO problems. See Upper Chattahoochee Riverkeeper v. City of Atlanta, No. 1:95-CV-2550 (N.D. Ga. Oct. 10, 1995).

39. The federal definition of "treatment works" means any devises or system used in the storage, treatment, recycling, and reclamation of sanitary sewage. 33 U.S.C. § 1292, ELR STAT. FWPCA § 402. A POTW is a "treatment works" and includes the sewers, pipes, or other conveyances transporting wastewater to that POTW. 40 C.F.R. § 122.2 (1995). The minimum federal technology-based (categorical) limitations for POTWs is defined as "secondary treatment" and applies to all discharges from the POTW. 40 C.F.R. § 133.102 (1995).


41. 33 U.S.C. § 1342, ELR STAT. FWPCA § 402.

42. See also subsequent text and infra notes 43-48, regarding Congress' progress toward recognizing the SSO problem.

43. Currently, some permits authorize SSOs when they are not feasible to avoid, such as circumstances beyond the control of the municipality. Other permits may allow such a discharge when specific requirements are met, such effluent limits and monitoring and reporting. See DRAFT SSO STRATEGY, supra note 40.

44. SSOs and CSOs are not bypasses as defined in the Draft SSO strategy and the CSO Policy—these overflow discharges occur before reaching and being treated at the POTW. The federal regulations defines "bypasses" as "intentional diversions of waste streams from any portion of a treatment facility." 40 C.F.R. § 122.41(m) (1995). The 1989 CSO Strategy then provides that "the treatment facility begins at the headworks [of the treatment plant] where equalization of the waste streams takes place." Combined Sewer Overflows Control Strategy, supra note 22.

45. EPA has stated that its definition of SSOs is a "working definition" and subject to further discussion. At present, the legal status of a particular discharge may hang on whether there is an applicable NPDES permit. See DRAFT SSO STRATEGY, supra note 40.

46. FWPCA §§ 308, 309, and 504 provide broad enforcement authority to address SSOs, just as they do CSOs. 33 U.S.C. §§ 1318, 1319, 1364, ELR STAT. FWPCA §§ 308, 309, 504. Note, however, the potential difference between CSO and SSO enforcement—a SSO might be considered a "bypasses" and thus should be considered in light of the regulations addressing bypasses. 40 C.F.R. § 122.41(m) (1995). Finally, as with CSOs, the same option regarding sewer connection bans applies.

47. For example, EPA Region 6 has issued over 80 administrativeorders to municipalities to address SSO discharge concerns. There are three recent EPA civil enforcement actions of note including Region 9's 1991 enforcement action against Honolulu, Hawaii, for lack of a pretreatment program and chronic SSOs. Poor maintenance had resulted in over 300 discharges and, in 1991, 50 million gallons of raw sewage spilled into Pearl Harbor. Region 4 has taken two civil SSO enforcement actions (Miami-Dade County, Florida, in 1993 and Jefferson County, Alabama, in 1994). Both cases involved old neglected systems and were initiated as a result of thousands of SSOs, nearly all of which were arguably preventable. In the case of the Jefferson County overflows, they resulted in the degradation of the Cahaba River. In the case of Miami-Dade, there were over 2,000 documented overflows from the collection system from 1989-1993 into streets, homes, the Biscayne Bay, and the Miami River. Also, the transmission line (Cross-Bay Line) that carries raw sewage under the Biscayne Bay was so corroded that it was in imminent danger of bursting.

48. The SSO Subcommittee is part of the Urban Wet Weather Flows Federal Advisory Committee. The Advisory Committee was established in early 1995 under the Federal Advisory Committee Act, 5 U.S.C. App. 2 (1995), to develop recommendations to coordinate the implementation of urban, municipal wet weather water pollution control programs. Notification of Establishment of an Advisory Committee to Address Urban Municipal Wet Weather Issues; Announcement of the Sanitary Sewer Overflow Subcommittee May 18-19, 1995, Meeting, 60 Fed. Reg. 21189 (May 1, 1995).

49. DRAFT SSO STRATEGY, supra note 40.

50. Id.

51. The bill was received by the Senate and referred to the Environment and Public Works Committee, which held its first hearing on FWPCA reauthorization on December 13, 1995.

52. H.R. 961, 104th Cong., 1st Sess. §§ 407, 408 (1995).

53. 33 U.S.C. § 1342, ELR STAT. FWPCA § 402.

54. H.R. 961, 104th Cong., 1st Sess. § 407 (1995).

55. Id. § 408 (1995).

56. Staffers Disagree on Definition of "Narrow" Senate CWA Bill, WATER POL'Y REP., Jan. 3, 1996 at 13.

57. H.R. 2099, 104th Cong., 1st Sess. 52 (1995).


26 ELR 10296 | Environmental Law Reporter | copyright © 1996 | All rights reserved