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Dam it: Environmental Law Implications Flow from New Reservoirs

Mon, 07/24/2017 - 10:28 -- admin25

by Jay Przyborski

The 2017 State Water Plan for Texas projects the state population will grow 70 percent between 2020 and 2070, from 29.5 to 51 million. As the primary strategy to confront the rising need for water, the Plan recommends construction of large reservoirs.

When new reservoirs are proposed, the usual legal battles over water rights and eminent domain garner headlines, obscuring environmental impacts that remain unknown to most citizens and lawmakers. New reservoirs, typically constructed by damming a river or stream, can eliminate thousands of acres of wetlands, streams, and other aquatic resources. Impacts to the surrounding environment are less obvious, but can be ecologically catastrophic. Reservoirs fragment riverine ecosystems, halt sedimentation, and alter water temperature downstream. Amidst the panoply of state and federal legal hurdles confronting a new reservoir proposal, the National Environmental Policy Act, or “NEPA,” and the Clean Water Act create frameworks for federal review of environmental impacts.

NEPA’s requirements are essentially procedural, obliging federal agencies to take a “hard look” at the environmental consequences of proposals for major federal actions significantly affecting the quality of the human environment. This proverbial “hard look” comes in the form of an Environmental Impact Statement, or “EIS,” wherein an agency (likely the Army Corps of Engineers for reservoir projects) reviews the impacts of the proposal, analyzes “reasonable” alternatives to the proposal that achieve the project purpose, and identifies mitigation measures. The EIS process ensures an agency will have the environmental information needed to make its decision, while also informing the public via NEPA’s public notice requirements.

The EPA plays a unique role in the NEPA process. Section 309 of the Clean Air Act requires EPA to comment on and rate other agencies’ EISs and refer to the Council on Environmental Quality any actions it deems environmentally unsatisfactory. EPA’s comments and ratings are only advisory, but they are closely monitored by project proponents and potential third party litigants.

While NEPA dictates process, the Clean Water Act determines outcome. Section 404 of the Clean Water Act requires a permit for discharge of dredge or fill material into waters of the United States, including wetlands. The implementing regulations, known as the 404(b)(1) Guidelines, create a framework requiring the permit applicant to avoid and minimize environmental impacts and to mitigate those impacts that are unavoidable. The Clean Water Act assigns the Army Corps of Engineers sole authority to issue 404 permits, but also designates EPA with an oversight role and the authority to deny or restrict any permit that will have certain unacceptable adverse impacts.

Similar to NEPA, the 404(b)(1) Guidelines require the Corps of Engineers to evaluate all “practicable” alternatives. Unlike NEPA, which merely requires identification of an environmentally preferred option, the Clean Water Act allows only the “least environmentally damaging practicable alternative,” or “LEDPA,” to be permitted. Reservoirs may not be permitted if less environmentally damaging alternatives such as conservation measures, groundwater storage, or smaller reservoirs are both practicable and achieve the project purpose. Proposed reservoirs impacting “special aquatic sites” such as wetlands (a likely scenario in the eastern half of Texas) face two challenging regulatory assumptions: (1) if a proposal does not require access to or siting within a special aquatic site, sites that do not involve special aquatic sites are presumed available, and (2) all alternatives that do not involve discharges to special aquatic sites are presumed to be less environmentally damaging.

If LEDPA analysis is the steepest regulatory hurdle for 404 permit applicants, compensatory mitigation can be the costliest. Born out of the longstanding national policy that there should be “no net loss” of wetlands, compensatory mitigation is the restoration, creation, enhancement, and preservation of wetlands, streams, and other aquatic resources to offset unavoidable impacts. The type of mitigation chosen and the ecological value of the impacted aquatic resources, among other factors, influence the number of acres or mitigation credits required, but permittees should expect to mitigate at a 1:1 ratio or greater.

Environmental impacts do not heavily influence how reservoir planners select or prioritize sites. Nevertheless, the tide is turning against surface storage as a preferred water supply strategy. As sites that can accommodate deep reservoirs become less available, shallow reservoirs with massive surface area are the remaining alternatives. Losses from evaporation make these water storage solutions inefficient. Meanwhile, new technologies will continue to make groundwater storage, water reuse, and conservation measures more financially viable. Until then, water planners would be wise to further incorporate environmental implications into planning.

Jay Przyborski is an attorney with the U.S. Environmental Protection Agency and can be reached at This article is not a product of the United States Government or the U.S. Environmental Protection Agency. The views expressed are his own and do not necessarily represent those of the United States or U.S. EPA.

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