Stormwater washes sediment, pathogens, and metals into surface waters, impairing the nation’s rivers, streams, and coastal shorelines. These impacts are largely the result of the built environment. As green space is developed, more impervious surfaces such as roofs, parking lots, and sidewalks are created, altering the land’s natural infiltration capability.
Because stormwater is inherently intermittent, diffuse, and influenced by decades-old land use and infrastructure decisions, the U.S. Environmental Protection Agency (EPA) historically struggled with regulating stormwater. Congress, through the Water Quality Act of 1987, amended the Clean Water Act (CWA) creating the existing regulatory framework in CWA § 402(p). EPA implemented that framework in two phases, Phase I in 1990 and Phase II in 1999, focusing on municipal (MS4s) and industrial stormwater. MS4s must comply with a unique “maximum extent practicable” (MEP) statutory standard. 33 U.S.C. §1342(p)(3)(B)(iii). Meeting this standard includes municipal ordinances placing requirements on private upstream facilities.
The trending issue of concern is stormwater from impervious surface—postconstruction stormwater—and using green infrastructure and low-impact development (LID) to address water quality impairment, while capturing the co-benefits like increased water supply and climate change adaptation. Though there is no single definition of “green infrastructure,” it generally refers to management systems that mimic nature by infiltrating or storing stormwater.
Green infrastructure has largely been embraced. The tension is how the issue fits—or does not fit—within the CWA’s regulatory program. On this question, there is disagreement. Ongoing litigation and future administrative actions, driven by environmental stakeholders (eNGOs), will not only impact regulated facilities and the nature of the CWA stormwater program, but will also influence where we get our water and how our cities are built.
After a decade of pressure from eNGOs, in 2009 EPA began a “Phase III” rulemaking to overhaul the existing stormwater regulations. The idea was to establish national performance or design requirements for newly developed and redeveloped sites—postconstruction standards—that could be achieved through green infrastructure and LID practices. The requirements could apply either through MS4 permits or directly to newly designated sources.
In 2014, EPA announced it would not revise the stormwater program. Instead, EPA would provide incentives, technical assistance, and tools to communities to encourage them to implement strong stormwater programs. See, e.g., EPA, Building Resilience to Drought in Ozone Park: Conceptual Design for Potable Water Offset Using Treated Urban Runoff, EPA-832-R-15-010 (June 2015), available at http://water.epa.gov/infrastructure/greeninfrastructure/gi_support.cfm. EPA intends to focus on leveraging existing regulatory requirements to strengthen MS4 permits. See Env. Protection Agency, Post-Construction Performance Standards & Water Quality-Based Requirements: A Compendium of Permitting Approaches, EPA-833-R-14-003 (June 2014), available at http://water.epa.gov/polwaste/npdes/stormwater/index.cfm. EPA is also pursuing green infrastructure as a form of injunctive relief in enforcement matters. For example, EPA recently modified a consent decree addressing combined sewer overflows to require large-scale green infrastructure projects rather than the construction of underground storage tunnels. First Amendment to Consent Decree, United States v. D.C. Water & Sewer Auth., No. 00-00183 (D.D.C. May 19, 2015), available at www2.epa.gov/enforcement/district-columbia-water-and-sewer-authority-district-columbia-clean-water-settlement.
While not as efficient as an EPA national rule, eNGOs are fully engaged in a permit-by-permit challenge strategy. As part of that effort, eNGOs are seeking additional leverage. In December 2014, eNGOs filed a petition for a writ of mandamus in the Ninth Circuit to enforce the order in Environmental Defense Center, Inc. v. EPA, 344 F.3d 832 (9th Cir. 2003). That decision remanded the 1999 Phase II stormwater regulation to EPA for revisions requiring National Pollutant Discharge Elimination System (NPDES) permitting authorities to review all notices of intent (NOI) submitted by small MS4s as part of the general permitting scheme and providing an opportunity for public review and comment of those NOIs.
In September 2015, EPA settled the matter with eNGOs, resulting in an expeditious rulemaking time line. By November 17, 2016, EPA must publish a final rule to fully comply with the Environmental Defense Center, Inc. v. EPA decision. It is uncertain whether EPA will simply revise the public participation process for MS4 permits or delve into substantive matters, such as creating minimum permit requirements based on an interpretation of the statutory MEP standard. At a minimum, the revised regulations will likely provide eNGOs with a greater ability to advocate for more stringent MS4 permit requirements.
Independent of EPA actions, states are already progressing with each new generation of their MS4 permits. In at least thirty-three states, MS4 permits include numeric postconstruction standards and nearly all MS4 permits include some language addressing impaired waters. However, eNGOs are aggressively challenging those MS4 permits as not stringent enough.
In Maryland, eNGOs challenged the Montgomery County MS4 permit, available at www.mde.state.md.us/programs/water/stormwatermanagementprogram/pages/programs/waterprograms/sedimentandstormwater/storm_gen_permit.aspx, which contains a mandate to install green infrastructure best management practices (BMPs) on 20 percent of the impervious surface within the county. In remanding the permit, a Maryland appellate court found it contains no consequential deadlines, requires no justification for why particular BMPs are selected, and fails to define sufficiently the universe of impervious surface. Md. Dept. of the Envt., et al. v. Anacostia Riverkeeper, et al., 112 A.3d 979 (Md. Ct. Spec. App. Apr. 2, 2015).
The Maryland Court of Appeals granted the petition for writ of certiorari. If the decision is upheld, it will impact not only future MS4 permits, but also the implementation of the historic, EPA-promulgated Chesapeake Bay Total Maximum Daily Load (TMDL), which was recently upheld in Am. Farm Bureau Fed’n v. EPA, 792 F.3d 281 (3d Cir. 2015), as the Bay states’ MS4 permits are viewed by EPA and the states as the “regulatory backbone” of achieving the goals of the TMDL by 2025.
In California, the State Water Resources Control Board (State Board) recently upheld the reissued Los Angeles MS4 permit, available at www.waterboards.ca.gov/losangeles/water_issues/programs/stormwater/municipal/, against thirty-seven administrative petitions challenging the permit. The State Board propounded the permit as a future model to address water quality, flood control, building resiliency as part of climate change adaptation, and importantly, in the face of severe drought, an increase in water supply through stormwater capture and reuse and groundwater aquifer recharge. Anyone flying over the City of Los Angeles can testify to the significant amount of impervious surface, with over 6,500 miles of streets, 10,000 miles of sidewalks, 900 linear miles of alleys and over 38,000 catch basins.
Under the Los Angeles MS4 permit, each MS4 must adopt ordinances requiring new development and redevelopment projects to retain stormwater on-site within specific design standards or complete project-specific alternatives such as off-site infiltration. Further, the permit requires MS4s to comply with numeric water quality-based effluent limits (WQBELs) based on Wasteload Allocations in approved TMDLs. The permit allows compliance with the WQBELs, in part, through the development of an enhanced watershed management program (EWMP) approved by the permitting authority. Notably, MS4s are required to develop and implement LID ordinances and green street policies in 50 percent of the area covered by the EWMP.
Although the Los Angeles MS4 permit is one of the most stringent MS4 permits in the country, in July 2015, eNGOs challenged the permit in state court, concerned that the EWMP provides a “safe harbor” for noncompliance with the permit’s WQBELs during the development and implementation of the EWMP. Nat. Res. Def. Council et. al. v. State Water Res. Control Bd., et al., No. BS156962 (Cal. Super. Ct. July, 2015).
Beyond MS4 permits, an alternative to addressing postconstruction stormwater is to designate and directly regulate those discharges. Nonmunicipal and nonindustrial stormwater discharges are generally not prohibited by CWA § 301(a), nor regulated through NPDES permits. However, EPA and the states have the ability to bring those discharges into the stormwater program through a process called designation. See 33 U.S.C. § 1342(p)(6), and 40 C.F.R. § 122.26(a)(9)(i)(C)-(D).
In 2013, troubled by the lack of progress on the “Phase III” stormwater rulemaking, eNGOs petitioned EPA Regions 1, 3, and 9 to use the residual designation authority to designate stormwater discharges from commercial, industrial, and institutional sites that allegedly contributed to water quality impairment in those Regions. In 2014, EPA Regions 3 and 9 denied the petition, but EPA Region 1 qualified its denial, leaving the door open.
eNGOs walked through that door in April 2015, filing complaints against EPA related to issues raised in the petition, alleging EPA Region 1 has a mandatory duty to designate and require NPDES permits for stormwater discharges from commercial, industrial, institutional, and high-density residential properties with impervious surface of one or more acres in select watersheds based on determinations made by EPA in approving applicable TMDLs. See Conservation Law Found. v. EPA, No. 15-00165 (D.R.I.) and No. 15-11727 (D. Mass.). Further, in September 2015, eNGOs submitted new petitions, available at http://switchboard.nrdc.org/blogs/jdyer/dear_epa_polluters_should_pay.html, to EPA Regions 3 and 9. The new petitions focus on different watersheds, seek to address the Regions’ basis for the 2014 denials, and, from the eNGOs’ perspective, establish a better record to challenge any EPA denial of the petitions. It is not clear that EPA has a mandatory duty to take action, but any precedent established via the complaints or new petitions—whether through litigation, a settlement, and/or future administrative action(s)—could significantly impact the scope of regulated stormwater.
The use of green infrastructure will continue to grow as a multipurpose tool. However, there are still barriers to universal use, including financing, problematic municipal ordinances, long-term maintenance, and uncertainty as a tool for regulatory compliance. See EPA, Green Infrastructure Opportunities and Barriers in the Greater Los Angeles Region, EPA-833-R-13-001 (August 2013), available at http://water.epa.gov/infrastructure/greeninfrastructure/gi_support.cfm.
In addition, CWA regulatory matters may create disincentives. In June 2015, EPA published its final “waters of the United States” regulation, which defines the scope of the CWA. 80 Fed. Reg. 37,058 (June 29, 2015). There are concerns green infrastructure may in the future be identified as a “waters of the United States,” either as part of a “tributary” system, “adjacent” water, or as a result of a case-specific “significant nexus” analysis. See 33 C.F.R. § 328.3(a)(5)-(7).
EPA sought to avoid such disincentives by adding an exclusion in the rule for “[s]tormwater control features constructed to convey, treat, or store stormwater that are created in dry land.” 33 C.F.R. § 328.3(b)(6). However, there are questions how the rule will be implemented, what is “dry land,” the use of natural features that were not “constructed,” and how to determine in the future if the location of the green infrastructure BMP was dry land at the time of construction. Maintenance is already a significant issue for green infrastructure. The possibility of needing a CWA § 404, permit to perform maintenance will disincentivize the utilization of green infrastructure as a tool.
There are also concerns that stormwater infiltration practices may require an NPDES permit. Infiltration or injection of captured stormwater into aquifers for groundwater recharge is an important green infrastructure BMP with co-benefits, especially an increase in water supply in the arid west. eNGOs are increasingly arguing that an NPDES permit is required for any discharge from a point source into groundwater that has a direct hydrologic connection to surface water.
For example, in Hawai’i Wildlife Fund v. County of Maui, 24 F. Supp. 3d 980 (D. Haw. 2014), the district court found the County of Maui’s injection of treated effluent into the ground via underground injection control (UIC) wells permitted by the Safe Drinking Water Act requires an NPDES permit. Under the court’s logic any green infrastructure BMP that could arguably be identified as a “point source” and infiltrates stormwater into the ground may require an NPDES permit, creating further disincentives.
While EPA made a policy decision not to revise the stormwater program, the next phase of stormwater regulation is here. Requirements imposed on and by MS4s will travel upstream through municipal ordinances, impacting a wide range of public and private facilities. Ongoing litigation, the issuance of more stringent NPDES permits, and other administrative actions have the potential to transform the stormwater program and are developments to follow closely.