Notice of Availability: Record of Decision for the Lower Columbia River (LCR) Channel Maintenance Plan (CMP) Final Dredged Material Management Plan (DMMP) - Environmental Impact Statement (EIS)
The U.S. Army Corps of Engineers, Portland District, announces the final Record of Decision (ROD) for the LCR CMP Final DMMP-EIS. The ROD formally approves the continued operations and maintenance (O&M) of the Lower Columbia River Federal Navigation Channel (FNC) for a minimum of 20 years by selecting Alternative 1 Refined - Maximize Placement as the Recommended Plan.
Decision and Recommended Plan
The U.S. Army Corps of Engineers (Corps), Portland District prepared an Environmental Impact Statement (EIS) dated May 1, 2026, for the Dredged Material Management Plan (DMMP) to support the continued operations and maintenance (O&M) of the Lower Columbia River (LCR) Federal Navigation Channel (FNC) for a minimum of 20 years. The NEPA process for this EIS began in 2017, prior to the 2025 recissions of the Council on Environmental Quality’s (CEQ) NEPA regulations previously found at 40 Code of Federal Regulations (CFR) Part 1500 (90 Federal Register [FR] 10610; February 25, 2025) or the recission of most subsections of the Corps’ agency-specific NEPA-implementing regulations previously found at 33 CFR Part 320. New Departmental NEPA-implementing procedures were contemporaneously issued in July of 2025, “Department of Defense National Environmental Policy Act Implementing Procedures (DoD NEPA Procedures),” with specification that the Corps will follow NEPA implementation guidance issued by the Department of Defense and any applicable guidance issued by the U.S. Army in implementing NEPA (90 FR 27857). However, these Departmental procedures specified that actions ongoing as of the effective date of the rule (July 3, 2025) will continue to use the rule in place at the time the action was started (90 FR 29463). Therefore, in order to be consistent with this guidance and avoid delay, the Corps applied CEQ’s prior NEPA regulations, the Corps’ prior agency-specific NEPA regulations (which can be found at 53 FR 3120–3137 (February 3, 1988), and the relevant guidance accompanying those regulations in completing this EIS.
Seven cooperating agencies, sponsor ports, tribes, and other interested parties provided information and review throughout the EIS process. The Corps and cooperators’ expertise, developed over decades of experience operating the projects, allowed for careful, comprehensive consideration of current, high-quality technical and scientific information, as well as expert analysis for a thorough evaluation of the actions. Based on these reports, the reviews by other Federal, State, and local agencies, Tribes, input of the public, and the review by my staff, I find the Recommended Plan to be technically feasible, environmentally justified, cost effective, in accordance with environmental statutes, and the public interest.
The Final EIS, incorporated herein by reference, evaluated various alternatives that would continue O&M in the study area. For this project, the least-cost, most-feasible plan was identified as the Recommended Plan, Maximize Placement. A software model called the Dredged Material Management Decisions Model (D2M2), developed by the Corps Engineer Research and Development Center (ERDC), was used to refine the Recommended Plan.
The Recommended Plan (Alternative 1 Refined) is to continue maintaining the Columbia River navigation channel to its authorized dimensions, 43 feet deep and 600 feet wide, for a minimum of 20 years. The fully funded cost estimate for the Recommended Plan is $562,981,000. The Recommended Plan includes the following new features: 17 in-water shallow placement sites; 7 confined aquatic placement sites with structures; 15 upland placement sites; 15 in-water transfer sites; and 52 shoreline sites (2 of which also include repair of existing pile dikes for stabilization). All these placement sites provide ecological and/or economic benefits.
Additionally, the Recommended Plan includes the following existing sites with remaining capacity and forecasted repairs, described in the No Action Alternative (NAA)/Base Condition:
• 19 upland placement sites
• 8 in-water transfer sites
• 5 shoreline sites with 1 site requiring repair of existing pile dikes
• Repair of 96 pile dike structures, and 16 major maintenance repairs of pile dike structures
• 20 sites (upland and shoreline placement sites) providing ecological and/or economic benefits
• In-water deep placement in the Columbia River
• Continued use of the Deep Water Site Ocean Dredged Material Disposal Site (DWS ODMDS)
Implementation of environmental compensatory mitigation and associated monitoring will ensure unavoidable adverse impacts are offset. Monitoring will continue until the mitigation is determined to be successful based on the identified criteria within the Implementation Plan included in Appendix J.7. Monitoring is expected to last for the duration of the period of implementation, or until necessary to achieve ecological success.
Initial management measures were identified for further analysis; those measures included several strategies which the Corps narrowed down further to reduce redundancy. From there, 30 management measures were identified which were screened into a final array of 12 management measures which were then evaluated against the objectives. These 12 management measures were grouped into two action alternatives.
In addition to a “no action” plan, two action alternatives were evaluated. The alternatives included Alternative 1 - Maximize Placement and Alternative 2 - Minimize Dredging. See chapters 2, 3 and 5 of the DMMP-EIS main report for alternative formulation and selection discussions. Alternative 1 - Refined Maximize Placement was identified as the environmentally preferable alternative and is the Recommended Plan.
The No Action Alternative relies on the use of in-water placement sites to manage dredged material, which will overload the system over time. In contrast, in-water deep placement attempts to emulate the process of sediment transport and morphology evolution that naturally occurs within and adjacent to the river’s thalweg zone (natural river deep-water flow area). In-water deep placement enables sediments to be redistributed back into the river’s morphology, where it sustains the river’s sediment budget, maintains habitats that rely on sediment, and stabilizes the river. Many of the in-water sites will reach capacity by Year 8 or sooner as additional dredged material is placed within these areas, and a higher proportion of the placed sediment will be transported directly back into the LCR FNC. As the LCR FNC receives additional shoaling sediment from overloaded in-water deep placement sites, the FNC will require increased annual O&M dredging and additional dredged material placement sites. Placement options are limited for the Base Condition. The Base Condition’s overloaded in-water placement site scenario will significantly increase the Corps’ efforts to maintain the LCR FNC, compromise the FNC’s reliability, and reduce habitat resilience within the LCR. The Base 3 Condition does not provide a reliable deep-draft FNC within the LCR, nor does it satisfy long-term needs of a sustainable river system.
A water quality certification pursuant to section 401 of the Clean Water Act was obtained from the Oregon Department of Environmental Quality (ODEQ) and Washington Department of Ecology (WDOE), dated November 24, 2025, and June 5, 2025, respectively. All applicable and feasible conditions of the water quality certification will be implemented to minimize adverse impacts to water quality.
FINDING
Technical, environmental, economic, and cost effectiveness criteria used in the formulation of alternative plans were those specified in the Water Resources Council’s 1983 Economic and Environmental Principles and Guidelines for Water and Related Land Resources Implementation Studies. All applicable laws, executive orders, regulations, and local government plans were considered in evaluation of alternatives. Based on the review of these evaluations, I find that benefits of the recommended plan outweigh the costs and any adverse effects. This Record of Decision completes the National Environmental Policy Act process.
The full Record of Decision is available here