Oregon Judge Considers USACE Detroit Lake Drawdown Injunction

• Oregon local governments are seeking a preliminary injunction to halt a U.S. Army Corps of Engineers plan to lower water levels in Detroit Lake.
• The proposed drawdown, part of a federal plan for 13 Willamette River Basin dams, aims to aid the downstream migration of juvenile Chinook salmon and steelhead.
• Plaintiffs, including the City of Salem, argue the action threatens their drinking water supply and infrastructure due to increased sediment and turbidity.
• Defendants, including environmental groups, contend the drawdown is essential for the recovery and survival of endangered fish species under the Endangered Species Act.
• A federal judge is currently weighing the likelihood of harm to both human water supply and protected fish populations.

The central legal question for U.S. District Judge Mustafa Kasubhai revolves around the potential for harm, as he noted the "biggest question for me is about likelihood of harm."

A federal judge in Oregon is currently considering a request from local governments to halt a U.S. Army Corps of Engineers (USACE) plan to significantly lower water levels in Detroit Lake. The proposed action, part of a broader strategy for 13 federally operated dams and reservoirs within the Willamette River Basin, aims to facilitate the downstream migration of juvenile fish. However, a city and county have urged the court to intervene, arguing the plan poses a substantial threat to both protected fish species and the region's drinking water supply.

The central legal question for U.S. District Judge Mustafa Kasubhai revolves around the potential for harm, as he noted the "biggest question for me is about likelihood of harm." The USACE had finalized a supplemental environmental impact statement (SEIS) earlier this year, outlining the proposal to reduce the Detroit Reservoir to an elevation of 1,395 feet during late fall and early winter, a level significantly below the minimum conservation pool of 1,450 feet. This Detroit Lake drawdown injunction request highlights the tension between federal environmental mandates and local resource management.

Marion County initiated legal action against the USACE in May, followed by the City of Salem in July. The Santiam Water Control District and the City of Stayton subsequently intervened as plaintiffs in the US Army Corps Detroit Lake lawsuit. These local entities contend that the planned drawdown carries substantial risks to the region's drinking water infrastructure, asserting that the USACE failed to adequately analyze and mitigate these potential impacts before making its decision.

The City of Salem, which relies solely on the North Santiam River for its drinking water, has voiced significant concerns regarding the proposed Detroit Lake drawdown. Detroit Lake, a nine-mile-long reservoir situated approximately 45 miles east of Salem on the North Santiam, is critical to the city's water infrastructure. The USACE plan involves slowly lowering the reservoir over two weeks, beginning in mid-November, and maintaining the reduced level for an additional two weeks.

Salem argues that this action would lead to increased sediment and turbidity, which would severely impact its slow sand filtration system. Such an impact would necessitate the city either to depend on emergency water reserves for extended periods or to undertake costly and time-consuming repairs to its filtration infrastructure. Daniel Quinley, an attorney representing Salem, emphasized this point, stating, "There’s only going to be no harm if there’s no sediment localization."

To mitigate these risks, Salem is seeking a preliminary injunction to prevent the USACE from proceeding with the drawdown. Alternatively, the city requests that the injunction mandate the USACE to halt the drawdown if turbidity levels reach or exceed 10 nephelometric turbidity units (NTU) and to refrain from resuming until levels fall below that threshold. Furthermore, plaintiffs are concerned about the forecast of an El Niño year, which could result in dry conditions and hinder water recovery in the region. Samantha Sondag, representing the Santiam Water Control District, warned of potential irreparable harm to water supply obligations if the Detroit Reservoir does not refill its minimum conservation pool by February 1, citing the current forecast as a risk factor in this Salem water supply challenge.

In contrast to the local governments' concerns, the defendants, including intervening nonprofits Northwest Environmental Defense Center and Native Fish Society, assert that the Detroit Lake drawdown is crucial for the protection of endangered fish species. Lauren Rule, an attorney representing these intervening defendants, highlighted the severity of the situation, arguing, "I think it’s important here that we’re not just talking about jeopardy; we’re talking about take."

The proposed drawdown is an integral component of the National Marine Fisheries Service’s (NMFS) long-term strategy to ensure the recovery and survival of Upper Willamette River Chinook salmon and steelhead. Both of these species are afforded protection under the Endangered Species Act. The specific objective of the drawdown is to aid the fall migration of juvenile fish by enabling them to navigate through the dam via regulating outlets, which are tunnels located lower on the dam face.

Juvenile fish typically remain within 25 to 50 feet of the water surface, making it unlikely for them to locate an outlet situated at a greater depth. Therefore, lowering the water level is presented as a necessary measure to facilitate their safe passage and contribute to the overall goals of the Endangered Species Act fish migration plan.

The legal challenge brought by Marion County and the City of Salem centers on the adequacy of the USACE's environmental impact statement and its assessment of risks. The plaintiffs argue that the federal agency's decision-making process for the Willamette River Basin dams did not sufficiently analyze and mitigate the potential harm to critical drinking water infrastructure. This raises significant questions about the thoroughness of the environmental impact statement adequacy, a common ground for challenging federal agency actions.

The conflict underscores the complex interplay between federal environmental protection mandates, such as those under the Endangered Species Act, and the vital interests of local communities in securing essential resources like drinking water. The court's decision on the preliminary injunction Oregon will have significant implications for how federal agencies balance these competing demands, particularly in regions where infrastructure and natural habitats are closely intertwined.

Ultimately, the judge's ruling will weigh the immediate and potential long-term harms to Salem's water supply against the imperative to protect endangered fish species, as mandated by federal law. The outcome will set a precedent for future environmental and infrastructure projects in the state and beyond, emphasizing the need for comprehensive risk assessment and mitigation strategies in federal planning.

This case illustrates the complex legal challenges arising when federal environmental mandates (Endangered Species Act) conflict with local government interests in water supply and infrastructure. Lawyers advising municipalities or water utilities should note the grounds for challenging federal agency actions, particularly regarding the adequacy of environmental impact statements and potential impacts on critical resources.

Source: Reporting based on CN coverage.