General Spellmon, Chief of Engineers, USACE signed the Chief’s Report on 20 August 2021.
Northwestern Division Commander signed a memo approving the report on 25 June 2021.

The Draft Integrated Feasibility Report and Environmental Assessment is posted in the Related Documents and Resources section. *This document is large and may take a moment to fully load.*

USACE has initiated a Feasibility Study focusing on Flood Risk Management of the Portland Metro Levee System in partnership with the Columbia Corridor Drainage Districts (CCDD) Joint Contracting Authority. CCDD consists of four drainage districts: Peninsula Drainage District #1, Peninsula Drainage District #2, Multnomah County Drainage District and the Sandy Drainage Improvement Company. The study area includes 27 miles of levees along the lower Columbia River within the Portland Metropolitan Area, running from Sauvie Island to the Sandy River.

The levee system is experiencing significant signs of structural vulnerabilities during high water, including sloughing, boils, and seepage. The three-year federal feasibility study process will lead to a recommendation to Congress for federal investment in addressing the problem areas in the Portland metropolitan area levee and drainage system.

The study will focus on developing an integrated plan to address potential system failures, meeting current levee safety standards, and identifying potential impacts from future changes including system consolidation, changing water flow conditions and potential operational changes to the Columbia River System.

The Non-Federal Sponsor on the project is the UFSWQD, which has been granted decision authority to act on behalf of the four drainage districts. The feasibility study is authorized in Section 216 of the Flood Control Act of 1970.

USACE, in partnership with UFSWQD, has been hosting ongoing informational meetings on the Portland Metro Levee System feasibility study. The events are open to the public and provide updates on the feasibility study including refinement of alternatives, technical information and analysis conducted to date, and the next steps in the feasibility study process. Past public meetings occurred in August, October and December of 2019. The presentations shown at those meetings are posted in the Related Documents and Resources section.

Past public engagement: USACE and UFSWQD held two scoping meetings in December 2018 to engage community members in discussing the study process, study milestones, and the development of preliminary alternative strategies for the reduction of flood risk in the Portland metropolitan area. Discussion also focused on modernization of the levees, flows and flood risk, geotechnical studies of the levees, and the economic risk and consequences posed by various flooding scenarios, as well as the effects on natural and cultural resources of alternatives considered.

In addition, USACE and UFSWQD held informational public meetings in January 2020 in the Oregon cities of Fairview and Portland.

The primary goal of the feasibility study is to reduce the risk of flood damages to the Portland metropolitan area, thereby reducing threats to life and safety.

Flood risk is made up of a variety of factors, beyond exclusively the condition of the levees themselves. These factors include: the hazard, system performance, exposure, vulnerability, and consequences.

The essential questions in determining flood risk are:

• What possible loading events could occur?
• How well will the levee system perform when the event occurs?
• What are the consequences if the levee does not perform as expected? What loss of life could occur?

In even simpler terms, flood risk is the probability of a flood multiplied by the consequences of that flood.