Stormwater

As the nation’s leading advocacy voice for municipal stormwater utilities across the country, NACWA is dedicated to protecting water quality; addressing large scale watershed impacts, such as flooding and erosion; and solving related modern-day challenges, such as water quality impairment from stormwater runoff and land-use impacts.

The Association and its individual members are committed to advancing robust, innovative programs and working collaboratively with regulators and stakeholders. The U.S. Environmental Protection Agency’s (EPA) MS4 General Permit Remand Rule, issued in early 2017, represents a change in the development and issuance of National Pollution Discharge Elimination System (NPDES) permits for small Municipal Separate Storm Sewer Systems (MS4s). And it has coincided with apparent shifts toward more restrictive, water quality-based requirements in all stormwater permits - Phase I and Phase II - and away from the more flexible maximum extent practicable (MEP) standard found in the Clean Water Act (CWA).

NACWA supports rational, cost-effective stormwater policies and regulations that allow stormwater utilities to prioritize investments in a way that will achieve the best water quality results. Its advocacy efforts include ensuring the availability of adequate funding and financing models for municipalities, as well as being a leading advocate for defending and preserving the MEP standard to which all MS4s are held.

Recent developments suggest municipal stormwater permitting will continue to increase in complexity. For example:

  • Bipartisan federal legislation has been introduced in Congress that would incorporate Integrated Planning and “green infrastructure” into the CWA.
  • Nutrient trading initiatives to reduce phosphorus and nitrogen loadings are becoming a popular solution in the Chesapeake Bay and elsewhere.
  • Increasing attention is being paid to pesticides and other emerging contaminants that are problematic in stormwater runoff.
  • Attempts by EPA are emerging to impose post-construction water quality and quantity controls in MS4 permits.

NACWA members interested in up-to-date information on stormwater issues should join the Stormwater Management Committee for all the latest information and updates.

For more information, contact Emily Remmel, NACWA’s Director, Regulatory Affairs.

NACWA Stormwater Resources

In the wake of the final Phase II Remand Rule in 2016, there has been a significant regulatory evolution within EPA’s NPDES permitting program for small MS4s. Given the regulatory uncertainty in the realm of MS4 permitting, and NACWA’s commitment to advancing robust stormwater programs, the Association has developed a Stormwater Permit Screening Program that will help MS4 permittees navigate the growing complexities often found in renewed stormwater permits. The Program is designed to assist utilities – particularly MS4 Phase II permittees – better understand permit language and options available to permittees during the permit issuance process.

The Stormwater Permit Screening Program works by offering permittees a high-level review of a draft permit and providing individualized feedback using a checklist of priority issues. This analysis is intended to help guide permittees through consideration of a number of factors and flag potentially impractical requirements. While the Screening Program does not provide legal advice, it may help inform permittees of possible permit language concerns and associated regulatory obligations.

The Screening Program reviews draft permits for several themes central to the Clean Water Act and MS4 permits, including maximum extent practicable (MEP) requirements, water quality standards, total maximum daily loads, impaired waters, and water quality trading.

Usually MS4 draft permits have a short turn-around for public comment (e.g., 30 days). If MS4s would like to participate and have NACWA review draft permit language, please let us know as soon as possible when draft language is available so that we can review and provide feedback.

The Stormwater Permit Screening Tool builds off NACWA’s 2018 MS4 Stormwater Permitting Guide that will aid all municipal stormwater managers—particularly in small and medium-sized communities—as they navigate the stormwater permitting process. The MS4 Permitting Guide is also intended to assist expert stormwater professionals seeking to answer more advanced related stormwater questions. Download the MS4 Stormwater Permitting Guide today!

NACWA also published a document in 2016, entitled Navigating Litigation Floodwaters: Legal Considerations for Enacting, Implementing & Funding Stormwater Programs, which outlines current legal issues associated with user-fee funded, municipal, separate-storm-sewer-systems stormwater programs, and a summary of selected legal decisions and pending cases.  The goal of the publication is to provide greater analysis on the types of legal issues impacting stormwater funding programs – and provide an overview of trends that are emerging based on the outcomes of key cases – to inform and prepare utilities that are creating, implementing or defending a stormwater program, utility or fee.

Waters of the United States (WOTUS) – Stormwater Exclusion

NACWA provided initial thoughts in a June 2017 letter to EPA regarding the Agency’s new effort to redefine “Waters of the United States” (WOTUS) under the Clean Water Act. NACWA’s comments on the new definition stressed the importance of maintaining and clarifying the new exclusion, found in the 2015 Clean Water Rule, for stormwater control features that are constructed to convey, treat or store stormwater. This exclusion reflects longstanding agency practice and will lead to more certainty over permitting and maintenance of green infrastructure/low-impact design stormwater features.

In 2019, EPA and the Department of the Army embarked on a two-step process to first repeal the 2015 Clean Water Rule and second to revise the definition of “waters of the United States.” NACWA commented on EPA’s proposed Navigable Waters Protection Rule in April 2019 urging both agencies to maintain existing exclusions for waste treatment systems, stormwater control features, wastewater recycling structures, and groundwater.

EPA finalized the Navigable Waters Protection Rule in April 2020 after receiving over 600,000 comments. The rule, which echoes NACWA’s calls to maintain exclusions for stormwater control features, went into effect June 22, 2020 and is currently being implemented in all states (except Colorado where the District Court for the District of Colorado stayed the effective date).

MS4 Phase II Remand Rule – Implementation

EPA issued the final MS4 General Permit Remand Rule—selecting the “Permitting Authority Choice” approach—with an effective date of January 2017. The rule applies only to Phase II MS4s.  The “Permitting Authority Choice” approach allows NPDES permitting authorities to choose between the two types of general permits: one that is comprehensive at the outset, and one that is less detailed but requires submission of comprehensive notices of intent (NOIs) which are approved by the agency and subject to public comment. NACWA provided EPA with comments.

As states work to implement the Remand Rule, a tangle of MS4 permit implementation issues are beginning to surface—including a shift away from the CWA’s traditionally flexible MEP mandate. As an example, Oregon proposed its first draft MS4 Phase II permit for public comment since the Remand Rule. NACWA is concerned that the draft permit would set a dangerous precedent that will have national implications if finalized “as-is.” The draft Phase II permit fails to mention the MEP standard and requires permittees “not cause or contribute to a violation of a water quality standard.” Read NACWA’s comments here. To assist municipalities navigate the complexities stemming from the Remand Rule, NACWA published the MS4 Stormwater Permitting Guide in 2018 as a resource for stormwater managers looking at their first MS4 permit iteration and for experts searching for answers to advanced MS4-related questions.

If your municipality or stormwater utility is having issues with implementation, please contact Emily Remmel, NACWA’s Director, Regulatory Affairs.

Stormwater Litigation

In 2016, EPA Region 1 issued NPDES permits for small MS4s in Massachusetts with an effective date of July 2017. A nearly identical permit was issued by EPA Region 1 for small MS4s in New Hampshire with an effective date of July 2018. Massachusetts and New Hampshire are two of only four states that do not have authority to implement NPDES permits and other CWA programs. Several interested parties appealed in the U.S. Court of Appeals for the First Circuit.

The permits required MS4s to comply with water quality standards, in addition to the requirement to reduce the discharge of pollutants to the maximum extent practicable (MEP) as required by the Clean Water Act (CWA), and impose strict compliance schedules for doing so.  The permits also attempted to regulate flow, in the form of specific retention requirements, which a federal court has previously held is not within EPA’s authority.

Given that the outcome of this case would likely set important legal precedent on how stormwater permits are written, NACWA supported its impacted members in challenging the most concerning elements of the permits. 

In April of 2020, after years of negotiation and mediation efforts and thanks in part to NACWA’s involvement, EPA published proposed modified permits for both Massachusetts and New Hampshire. NACWA supports EPA’s proposed modifications as the revisions omit the unlawful “cause and contribute to a water quality exceedance” and now include an offramp that allows municipalities a more flexible path forward for demonstrating when pollutant reduction is no longer practicable.

NACWA views the permit modifications as a positive step forward from the original permits that significantly departed from the statutory boundaries of the Clean Water Act and may have set a negative precedent for stormwater agencies to adhere to overly strict and prescriptive numeric water quality standards and total maximum daily load requirements.

NACWA is committed to engaging in legal actions over municipal stormwater permits where appropriate to ensure the permits conform with federal law and provide MS4s with the needed flexibility to make the best investments for water quality improvement.