EPA's new NPDES Phase II stormwater rule has been issued and will have far-reaching implications for stormwater professionals and public works officials.

By David A. Woelkers

On December 8, 1999, the Unites States Environmental Protection Agency (EPA) published the stormwater Phase II final rule in the Federal Register. The issuance of the rule started a clock that has municipalities, the industry, and stormwater professionals racing to understand and evaluate its implications. Although Phase II permit coverage will not be mandatory until March 10, 2003, the amount of preliminary work to get permit coverage can be extensive, and those who will be regulated should now begin the process of determining what they need to do to be in compliance when the Phase II storm arrives.
      The Phase II rule is an extension of the National Pollutant Discharge Elimination System (NPDES) stormwater program. The Phase I rule was issued in 1990 and covered medium and large municipal separate storm sewer systems (MS4s) - cities or jurisdictional entities serving populations over 100,000. In addition, operators of construction activities disturbing more than 5 ac. and 11 categories of industrial activities were required to obtain permit coverage under Phase I.
      Phase II will extend NPDES stormwater permit requirements to small MS4s and construction activities disturbing more than 1 ac. Unlike the Phase I monitoring requirements, however, the Phase II rule has taken a more flexible approach. Those municipalities regulated under Phase II will not have to establish pollutant characterization of stormwater quality by conducting analytical testing. The implementation of stormwater discharge management practices, or best management practices (BMPs), will likely be sufficient in order to meet compliance with the six minimum measure requirements of Phase II.
      The Phase II stormwater rule will automatically cover operators of MS4s who are located within an "urbanized area" that has a total population of 50,000 or more and a density of 1,000 persons per square mile. These urbanized areas usually include several different jurisdictions and are based on US census counts. current municipalities that will automatically be covered are listed as appendix 6 to the Phase II final rule (www.epa.gov/owm/sw/phase2). In addition, more municipalities will be added when the 2000 census is completed. These new areas will still have to comply by March 2003 even though they might not know until late 2001 when the 2000 results are released. Thus, growing population areas should plan ahead.
      A "municipality" is defined by the rule to include not only what is traditionally thought of as a municipality, such as cities, towns, and villages, but also federal installations and military bases, Native American lands, state agencies, and counties. The definition also includes state-owned or -operated departments of transportation, universities, hospitals, and even local drainage, sewer, or water conservation districts that might operate separate storm sewer systems.
      In addition, the definition of what constitutes a "separate storm sewer system" includes any method of conveying surface water, including streets, gutters, ditches, swales, or any other manmade structure that alters and/or directs wet-weather flows. Thus, the impact of the Phase II rule will be far-reaching.
      Along with the automatically designated MS4s, the Phase II rule also requires the NPDES Permitting Authority to establish criteria for including at a minimum those MS4s located in population areas of at least 10,000 if it determines that wet-weather flow discharges could cause an adverse impact on the quality of receiving waters. Permitting authorities may also include municipalities as designated MS4s with populations as low as 1,000. In most cases these designations must occur on or before December 9, 2002. Municipalities with these MS4s will have 180 days from designation to obtain permit coverage.
      Finally, MS4 operators with populations of fewer than 1,000 outside of automatic and designated areas may also need stormwater permits for discharge if permitting authorities determine that the MS4 is contributing substantially to pollutant loading of a physically interconnected and regulated MS4.

Municipal Permit Requirements

 A municipality’s individual permit application or notice of intent for coverage under a general permit must include descriptions of the BMPs - as well as their respective measurable goals - that will be used to meet the following six minimum measures.

1. Public Education and Outreach. This measure must include a program designed to educate the public about the impacts of stormwater discharges on receiving waters and what individuals can do to prevent stormwater pollution.
2. Public Participation and Involvement. This measure must include a procedure for giving the public an opportunity to actually participate in both the development and implementation of a stormwater program.
3. Illicit Discharge Detection and Elimination. Regulated municipalities must develop a plan with mechanisms designed to locate and eliminate discharges into storm sewers from sources other than stormwater. This plan must include a complete map of all outfalls and identification of locations and sources of any water entering a system.
4. Construction-Site Runoff Control. Regulated municipalities must have a regulatory mechanism in place for erosion and sediment control as well as BMPs for preventing or reducing other pollutants associated with construction activity. It is important to note that this measure does not relieve the requirements of a construction-site operator to obtain an independent NPDES permit for sites larger than 1 ac. The permitting authority, however, can specifically reference qualifying local programs in the NPDES general permit requirements so the construction operator doesn’t need to follow two different sets of requirements.
5. Postconstruction Runoff Controls. Regulated municipalities must have a program requiring new and redevelopment projects to implement controls on sites, which will reduce pollutant loads in stormwater runoff.
6. Pollution Prevention and Good Housekeeping. Regulated municipalities must have an operation and maintenance program to prevent or reduce pollutant runoff from municipal operations.

Planners will have to prepare in advance to eliminate illicit connections into MS4s.

     While the above six measures are the minimum required by EPA, the rule allows for states with NPDES permitting authority to develop permits that may require more stringent measures to meet water-quality requirements. In addition, municipalities may also develop stormwater regulations that go beyond the requirements of Phase II.
      The Phase II rule is drafted to encourage development of a stormwater control plan that fits local conditions and allows flexibility by local authorities to meet their individual needs. Those MS4s that wait until the last minute, however, are likely to face prescriptive requirements that will not take into account local conditions. Therefore, officials, planners, and stormwater professionals need to start the planning process now.

Industrial Impacts

 In addition to the changes noted above for municipal and construction activities, Phase II will also impact Phase I-regulated industrial activities in two ways. Under Phase II all industrial activities will now be eligible for no-exposure waivers instead of only light industries defined in category 11. However, category 11 industries will now need to file waivers or obtain a permit; under Phase I, category 11 industries with no exposure did not need to file these waivers.
      Finally, under the Intermodal Surface Transportation and Efficiency Act moratorium, municipalities did not need permits for their industrial activities, such as maintenance yards. This moratorium will end on March 10, 2003, and all municipalities will then need an NPDES permit for regulated industrial activities.

BMP Selection

Since Phase II is a narrative rule that only requires the implementation of BMPs to achieve compliance, selection of the proper mix of BMPs appropriate to the municipality becomes critical. The Phase II rule requires that EPA and permitting authorities issue BMP menus for each minimum measure to assist MS4s in developing the stormwater management program BMP "toolbox." These menus will include both structural and nonstructural BMPs.
Nonstructural BMPs may include:

• educational materials;
• school stormwater programs;
• public meetings and citizen groups;
• volunteer cleanups, monitoring programs, and Adopt-A-Storm Drain programs;
• illicit discharge detection programs;
• regulatory ordinances and other regulatory mechanisms, including:
• prohibitions on nonstorm discharges into separate storm sewers,
• requirements for control of erosion, sediment, and other pollutants on construction sites,
• site-plan approval processes requiring postconstruction stormwater controls;
• requirements for installation of controls at existing sites that are likely sources of pollutant runoff,
• BMP operation and maintenance requirements with regulatory enforcement provisions;
• procedures for inspecting and monitoring structural BMPs;
• street sweeping, catch-basin cleaning, and organic yardwaste controls;
• training materials and municipal maintenance activities and schedules;
• recycling and pollution prevention programs.

     Structural BMPs may include:

• vegetative BMPs such as constructed wetlands, swales, filter strips, and rain gardens;
• infiltration BMPs (with pretreatment where necessary for groundwater and wellhead protection) such as basins, trenches, dry wells, sand filters, and porous pavement;
• detention and retention methods for controlling both volume and quality of water flow into MS4s and receiving waters;
• treatment controls such as separators, filtration devices, catch-basin inserts, and skimmers;
• outfall and drain grates.

     All of the above are just examples of BMPs that could be used to meet Phase II requirements. The rule does not set limits as to which BMPs can be used, and regulated municipalities can develop their own list to meet their needs if they wish. John Kosco at EPA’s Office of Water, who is directing the development of EPA’s Phase II BMP menu, points out that the information that will be set forth on the menu is not intended to be limiting but rather to be used as guidance.
      With many proprietary technologies entering the marketplace, there may be concern as to what BMP will be acceptable. Officials and stormwater professionals need to do research to ensure that various claims regarding BMP capabilities are accurate. To that end, EPA - through its Environmental Technology Verification Program - is partnering with NSF International (a public health and safety company) and the Civil Engineering Research Foundation to develop protocols and verification procedures for proprietary wet-weather flow technologies. These will guide decision-makers toward available, dependable controls. In addition, various BMP databases are obtainable through the Internet.

Conclusion

With the approaching storm of Phase II, there is a sense of apprehension among municipalities with MS4s that are trying to understand and deal with numerous new issues and mandates. It is clear that the days when stormwater management meant only "moving the water" are over. Yet, by carefully planning in advance, municipalities and others affected by the NPDES Phase II stormwater regulations, such as construction-site operators, will be able to promote the long-term quality of local water resources and substantially reduce the costs of implementation and compliance.

The following individuals reviewed and contributed to this article: John Kosco, EPA Office of Wastewater Management, director of Phase II stormwater toolbox BMP menu; Dave Drullinger, Michigan DEQ, SWQD-Stormwater Permit Section; Eric Rortvedt, Wisconsin DNR, stormwater coordinator; Janis Bobrin, drain commissioner, Washtenaw County, MI; Jerry Faye, APWA national president, State of Washington Transportation Improvement Board executive director; Jim Scholl, Tetra-Tech MPS; Andrew J. Reese, vice president, Odgen Environmental and Energy Services; and Richard Bradley, HSE coordinator, Mid-Continent Business Unit, BP Amoco.