490 U.S. 360 (1989), 87-1704, Marsh v. Oregon Natural Resources Council

Docket Nº:No. 87-1704.
Citation:490 U.S. 360, 109 S.Ct. 1851, 104 L.Ed.2d 377, 57 U.S.L.W. 4504
Party Name:Marsh v. Oregon Natural Resources Council
Case Date:May 01, 1989
Court:United States Supreme Court

Page 360

490 U.S. 360 (1989)

109 S.Ct. 1851, 104 L.Ed.2d 377, 57 U.S.L.W. 4504



Oregon Natural Resources Council

No. 87-1704.

United States Supreme Court

May 1, 1989

Argued January 9, 1989




The Elk Creek Dam is part of a three-dam project designed to control the water supply in Oregon's Rogue River Basin. The Army Corps of Engineers (Corps) completed an Environmental Impact Statement (EIS) for the Elk Creek project in 1971, and, in 1980, released its final Environmental Impact Statement, Supplement No. 1 (FEISS). Since the Rogue River is a premier fishing ground, the FEISS paid special heed to water quality, fish production, and angling, and predicted that the Elk Creek Dam would have no major effect on fish production, but that the effect of the Lost Creek and Elk Creek Dams on turbidity might, on occasion, impair fishing. After reviewing the FEISS, the Corps' Division Engineer decided to proceed with the project and, in 1985, Congress appropriated funds for construction of the dam, now one-third completed. Respondents, four Oregon nonprofit corporations, filed an action in the District Court to enjoin construction of the Elk Creek Dam, claiming that the Corps had violated the National Environmental Policy Act of 1969 (NEPA) by failing, among other things, to describe adequately the environmental consequences of the project; to include a "worst case analysis"; and to prepare a second supplemental EIS to review information in two documents developed after 1980. The first -- the Cramer Memorandum -- is an internal memorandum, prepared by two Oregon Department of Fish and Wildlife (ODFW) biologists based on a draft ODFW study on the effects of the Lost Creek Dam, suggesting that the Elk Creek Dam will adversely affect downstream fishing; and the second is a United States Soil Conservation Service (SCS) soil survey containing information that might be taken to indicate greater downstream turbidity than did the FEISS. The District Court denied relief on all claims and held, inter alia, that the Corps' decision not to prepare a second supplemental EIS to address the new information was reasonable. The Court of Appeals reversed, holding, among other things, that the FEISS was defective because it did not include a complete mitigation plan and "worst case analysis," and, with regard to the failure to prepare a supplemental EIS, that the ODFW and SCS documents brought to light significant new information

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that was probably accurate, and that the Corps' experts failed to evaluate with sufficient care.


1. The Court of Appeals' conclusions that the FEISS was defective because it did not include a complete mitigation plan and a "worst case analysis" are erroneous for the reasons stated in Robertson v. Methow Valley Citizens Council, ante p. 332. Pp. 369-370.

2. The Corps' decision that the FEISS need not be supplemented is not arbitrary and capricious, and should not be set aside. Pp. 370-385.

(a) An agency must apply a "rule of reason" and prepare a supplemental EIS if there remains "major Federal actio[n]" to occur, and if the new information will affect the quality of the human environment in a significant manner or to a significant extent not already considered. Although not expressly addressed in NEPA, such a duty is supported by NEPA's approach to environmental protection and its manifest concern with preventing uninformed action, as well as by Council on Environmental Quality and Corps regulations, both of which make plain that, at times, supplementation is required. Pp. 370-374.

(b) Court review of the Corps' decision is controlled by the "arbitrary and capricious" standard of the Administrative Procedure Act, 5 U.S.C. § 706(2)(a). Respondents' supposition that the determination that new information is "significant" is either a question of law or of ultimate fact and, thus, "deserves no deference" on review is incorrect, since the resolution of this dispute involves primarily issues of fact concerning contentions that the new information is accurate and undermines the FEISS' conclusions, and that the Corps' review was incomplete, inconclusive, or inaccurate. Because analysis of the documents requires a high degree of technical expertise, this Court must defer to the informed discretion of the responsible agency. However, courts should not defer to an agency without carefully reviewing the record and satisfying themselves that the agency has made a reasoned decision based on its evaluation of the new information. Pp. 375-378.

(c) The Corps conducted a reasoned evaluation of the relevant information in a formal Supplemental Information Report (SIR) and reached a decision that was not arbitrary and capricious. The Corps carefully scrutinized the Cramer Memorandum -- which did not reflect the neutral stand of ODFW's official position -- and, in disputing its accuracy and significance, hired two independent experts who found significant fault in the methodology and conclusions of the underlying draft ODFW study. Although the SIR did not expressly comment on the SCS survey, in light of in-depth studies conducted in 1974 and 1979, its

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conclusion that "turbidity effects are not expected to differ from those described in the 1980 EISS" provided a legitimate reason for not preparing a supplemental FEISS to discuss turbidity. Pp. 378-385.

832 F.2d 1489, reversed and remanded.

STEVENS, J., delivered the opinion for a unanimous Court.

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STEVENS, J., lead opinion

JUSTICE STEVENS delivered the opinion of the Court.

This case is a companion to Robertson v. Methow Valley Citizens Council, ante p. 332. It arises out of a controversial decision to construct a dam at Elk Creek in the Rogue River Basin in southwest Oregon. In addition to the question whether an Environmental Impact Statement (EIS) prepared pursuant to the National Environmental Policy Act of 1969 (NEPA), 83 Stat. 852, 42 U.S.C. § 4321 et seq., must contain a complete mitigation plan and a "worst case [109 S.Ct. 1854] analysis," which we answered in Robertson, it presents the question whether information developed after the completion of the EIS requires that a supplemental EIS be prepared before construction of the dam may continue.


In the 1930's, in response to recurring floods in the Rogue River Basin, federal and state agencies began planning a major project to control the water supply in the Basin.1 See, e.g., ch. 346, 49 Stat. 439. In 1961, a multiagency study recommended the construction of three large dams: the Lost Creek Dam on the Rogue River, the Applegate Dam on the Applegate River, and the Elk Creek Dam on the Elk Creek near its confluence with the Rogue River. See H.R. Doc. No. 566, 87th Cong., 2d Sess., 7-89 (1962). The following year, Congress authorized the Army Corps of Engineers (Corps) to construct the project in accordance with the recommendations

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of the 1961 study. See Flood Control Act of 1962, Pub.L. 87-874, § 203, 76 Stat. 1192-1193. The Lost Creek Dam was completed in 1977, and the Applegate Dam was completed in 1981.

Plans for the Elk Creek Dam describe a 238-foot-high concrete structure that will control the runoff from 132 square miles of the 135-square-mile Elk Creek watershed. When full, the artificial lake behind the dam will cover 1,290 acres of land, will have an 18-mile shoreline, and will hold 101,000 acre-feet of water. The dam will cost approximately $100 million to construct, and will produce annual benefits of almost $5 million. It will be operated in coordination with the nearby Lost Creek Dam, where the control center for both dams will be located. Its "multiport" structure, which will permit discharge of water from any of five levels, makes it possible to regulate, within limits, the temperature, turbidity,2 and volume of the downstream flow. Although primarily designed to control flooding along the Rogue River, additional project goals include enhanced fishing, irrigation, and recreation.

In 1971, the Corps completed its EIS for the Elk Creek portion of the three-dam project and began development by acquiring 26,000 acres of land and relocating residents, a county road, and utilities. Acknowledging incomplete information, the EIS recommended that further studies concerning the project's likely effect on turbidity be developed. The results of these studies were discussed in a draft supplemental EIS completed in 1975. However, at the request of the Governor of Oregon, further work on the project was suspended,

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and the supplemental EIS was not filed to make it possible to analyze the actual consequences of the construction of the Lost Creek Dam, which was nearing completion, before continuing with the Elk Creek project. Following that analysis and the receipt of a statement from the Governor that he was "extremely interested in pursuing construction of the Elk Creek [109 S.Ct. 1855] Dam,"3 the Corps completed and released its final Environmental Impact Statement, Supplement No. 1, in December, 1980.

Because the Rogue River is one of the Nation's premier fishing grounds, the FEISS paid special heed to the effects the dam might have on water quality, fish production, and angling. In its chapter on the environmental effects of the proposed project, the FEISS explained that water quality studies were prepared in 1974 and in 1979, and that "[w]ater temperature and turbidity have received the most attention." FEISS 33. Using computer simulation models, the 1974 study predicted that the Elk Creek Dam might, at times, increase the temperature of the Rogue River by one to two degrees Fahrenheit and its turbidity by one to three JTU's.4 Ibid. The 1979 study took a second look at...

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