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Home    |   Currents   |   Clean Water Act Liability for Stormwater Discharge Regardless of Who Muddied the Waters

Clean Water Act Liability for Stormwater Discharge Regardless of Who Muddied the Waters

Jul 19, 2011

CaliforniaWaste & PollutionWater

Yana Welinder[*]


Regulating pollution from stormwater that flows over structures and paved surfaces, collecting waste and sediments and ultimately spilling into rivers and oceans, can be a true “administrative nightmare.”[1] However, on March 10, 2011, the Ninth Circuit clarified that, when stormwater pollution cannot be attributed to any particular polluter, liability under the Clean Water Act (CWA)[2] can nevertheless be imposed upon the entity that controls the discharge of stormwater into watercourses.[3] As such, the court in Natural Resources Defense Council v. County of Los Angeles held the Los Angeles County Flood Control District (District) liable for excess stormwater pollution detected by monitoring stations located in storm-sewer systems channeling stormwater to the Los Angeles River and the San Gabriel River. San Gabriel
San Gabriel River. Photo credit to Eazylanish.

National Pollution Discharge Elimination System Permits Under the Clean Water Act

The CWA prohibits “the discharge of any pollutant by any person”[4] into “navigable waters from any point source” unless done in compliance with the provisions of the CWA.[5] Such pollutants include “dredged spoil, solid waste, incinerator residue, sewage, garbage, sewage sludge, munitions, chemical wastes, biological materials, radioactive materials, heat, wrecked or discarded equipment, rock, sand, cellar dirt and industrial, municipal, and agricultural waste.”[6] A point source is “any discernible, confined and discrete conveyance, including but not limited to any pipe, ditch, channel, tunnel, conduit, well, discrete fissure, container, rolling stock, concentrated animal feeding operation, or vessel or other floating craft, from which pollutants are or may be discharged.”[7]

To discharge pollutants from a point source in compliance with the CWA, one must first obtain a National Pollutant Discharge Elimination System (NPDES) permit, which requires compliance with numerous requirements, including effluent limitations,[8] water-quality standards,[9] water monitoring and public reporting obligations, as well as specific discharge requirements.[10] In California, the State Water Resources Control Board and nine regional water quality control boards issue NPDES permits.[11] Discharges from the District, the County of Los Angeles (County), and eighty-four incorporated municipalities in the County fall under the jurisdiction of the Los Angeles Regional Water Quality Control Board.

Natural Resources Defense Council v. County of Los Angeles

The District operates an extensive flood-control and storm-sewer infrastructure (known as the “MS4”) that collects stormwater runoff from thousands of storm drains located in various municipalities in the County and channels it to several watercourses that eventually drain into the Pacific Ocean.[12] Before the stormwater enters the MS4, it flows over the sprawling development of the County and collects various pollutants such as suspended metals, sediments, algae-promoting nutrients, floatable trash, used motor oil, raw sewage, pesticides, and other toxic contaminants. The discharge of such pollutants into watercourses is governed by a NPDES permit held jointly by the District, the County, and the eighty-four municipalities within the County.[13] This permit includes a requirement that the District operate monitoring stations to measure the level of pollutants in the stormwater that it discharges into watercourses.

Two environmental organizations—the Natural Resources Defense Council and Santa Monica Baykeeper—brought a citizen suit against the District and the County under the CWA. The organizations alleged that the District and the County violated their NPDES permit by discharging overly polluted stormwater runoff into the Los Angeles River, the San Gabriel River, the Santa Clara River, and Malibu Creek, as measured by the monitoring stations for those four watercourses between 2002 and 2008.[14] The U.S. District Court for the Central District of California entered a partial summary judgment for the District and the County, while denying the environmental organizations’ motion for summary judgment. The court found that the organizations failed to present evidence to establish that the District and the County were responsible for the stormwater discharge.[15]

On appeal, the District argued that the MS4 merely channels pollutants created by other municipalities or industrial NPDES permit holders. The Ninth Circuit rejected this argument, stating that, for the purposes of the CWA, it is irrelevant whether the discharger of polluted stormwater adds or generates the pollution.[16] The court echoed the Fourth Circuit’s statement in West Virginia Highlands Conservancy, Inc. v. Huffman that “the statute takes the water’s point of view: water is indifferent about who initially polluted it so long as pollution continues to occur.”[17] Because the District controlled the “point source”—the MS4—it was liable for the discharge of pollutants from that point source into the watercourses.

The court further held that the environmental organizations were entitled to a summary judgment with respect to the MS4’s discharges into the Los Angeles River and the San Gabriel River because the monitoring stations for those watercourses were located inside the MS4 before the point of discharge.[18] By contrast, the monitoring stations for the Santa Clara River and the Malibu Creek were located within the actual watercourses.[19] For those watercourses, the court stated that the environmental organizations would need to present evidence other than the measurements from the monitoring stations to rule out other potential contributors of pollution in those watercourses.[20] The court also found that there was insufficient evidence that the excess pollution measured by the monitoring systems was discharged into any of the four watercourses from storm-sewer systems controlled by the County, which is a separate legal entity from the District.[21]

LA River
Los Angeles River. Photo credit to dsearls.


By applying this end-of-pipe analysis, the court clarified how liability can be imposed under the CWA in situations when it is impossible to pinpoint which particular entity or operation contributed to the stormwater pollution. The court indicated that the CWA does not demand “that Plaintiffs engage in the Sisyphean task of testing particular storm drains in the County for the source of each pollutant.”[22] As a result of this holding, to avoid future liability, entities that control a “point source” will need to treat polluted stormwater before it is discharged in watercourses, even if they have not contributed to the pollution.

This is the second Ninth Circuit holding in less than a year to expand the scope of liability under the CWA. In the earlier case, Northwest Environmental Defense Center v. Brown, the court held that stormwater runoff flowing from roads “designed and constructed with systems of ditches, culverts, and channels that collect and convey stormwater runoff” constituted a “point source” for which an NPDES permit was required.[23] Read together, these two cases identify many entities that can potentially be held liable for discharge of polluted stormwater under the CWA. However, a very recent District Court decision has limited the potentially expansive scope of Brown, holding that pollutants discharged when stormwater flows down wooden utility poles need not to be regulated by a NPDES permit because such poles do not constitute a “point source.”[24] While entities controlling utility poles or other non-point source structures may not be liable for the pollution they generate, liability can be imposed on entities controlling the streets upon which the polluted stormwater flows if such streets are designed to channel stormwater toward a point source. Consequently, at least in theory, no stormwater pollution goes unregulated.

Santa Clara

Santa Clara River draining into the Pacific Ocean, the ultimate destination of California stormwater runoff and pollution. Photo credit to …-Wink-….

[*] Yana Welinder is an associate at Colantuono & Levin in Los Angeles, where she serves as Assistant City Attorney for the cities of Calabasas and Los Alamitos, advises clients on public law, and represents public entities in litigation.

[1] See 131 Cong. Rec. 15,657 (1985) (statement of Sen. Malcolm Wallop) (discussing the possible consequences of a statute to regulate individual sources of stormwater runoff).

[2] See Clean Water Act, 33 U.S.C. §§ 1251–1387 (2006).

[3] See Natural Res. Def. Council v. Cnty. of Los Angeles, 636 F.3d 1235 (9th Cir. 2011).

[4] Clean Water Act, 33 U.S.C. § 1311(a) (2006).

[5] Id. § 1362(12).

[6] Id. § 1362(6).

[7] Id. § 1362(14).

[8] Effluent limitations are restrictions on “concentrations of chemical, physical, biological, and other constituents which are discharged from point sources into navigable waters.” Id. § 1362(11). The restrictions are based on facility categories and are developed without regard to the existing pollution levels in watercourses.

[9] Water quality standards are additional restrictions that take into account the existing pollution levels in the watercourse where the pollutants are to be discharged.

[10] See Clean Water Act, 33 U.S.C. § 1342(a) (2006); see also id. §§ 1311, 1312, 1316–1318, 1343.

[11] The U.S. Environmental Protection Agency authorizes the State of California to issue NPDES permits and develop water-quality standards. The State, in turn, designated the State Water Resources Control Board as the principle agency to develop and enforce such standards.

[12] See Natural Res. Def. Council v. Cnty. of Los Angeles, 636 F.3d 1235, 1237 (9th Cir. 2011).

[13] See id. at 1240.

[14] See id. at 1242.

[15] See id. at 125051.

[16] See id. at 125253.

[17] W. Va. Highlands Conservancy, Inc. v. Huffman, 625 F.3d 159, 167 (4th Cir. 2010).

[18] See Natural Res. Def. Council v. Cnty. of Los Angeles, 636 F.3d 1235, 1252 (9th Cir. 2011).

[19] See id. at 1253.

[20] See id. at 125354.

[21] See id. at 1254.

[22] See id. at 1252.

[23] Nw. Envtl. Def. Ctr. v. Brown, No. 07-35266, 2011 WL 1844060, at *1 (9th Cir. May 17, 2011).

[24] See Ecological Rights Found. v. Pac. Gas and Elec. Co., No. C 09‒03704 SBA, 2011 WL 1302229, at *5 (N.D. Cal. Mar. 31, 2011).

Copyright 2011 Yana Welinder. All rights reserved.

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