The Floodplain Resilience Plan will reduce the impacts of future flooding on those who live and work in, or close to, Portland’s floodplains. The plan also aims to protect floodplain habitat for endangered and threatened fish species. This effort responds to Federal Emergency Management Association (FEMA) guidance by updating the rules that apply to new development along the edges of Portland’s rivers and streams. The plan and related projects will ensure that homes and businesses located in flood-prone areas continue to qualify for federal flood insurance and disaster relief funds.
In the fall of 2022, the Floodplain Resilience Plan Discussion Draft was presented to the (former) Planning and Sustainability Commission (PSC), an advisory body responsible for reviewing and recommending land use proposals to City Council. In September of 2022, the PSC held a public hearing where public testimony was received and considered. After subsequent work sessions, the PSC voted on November 22, 2022, to make a small number of amendments to the zoning code (Title 33) and maps and to forward their recommendations to City Council as the Floodplain Resilience Plan Recommended Draft.
The Floodplain Resilience Plan Recommended Draft is now available for public review and testimony.
Read the Recommended Draft Report
Read the Recommended Draft Amendments Memo
The plan amends the zoning code (Title 33) and associated maps in the following ways:
- Expand environmental zones to apply habitat protections to floodplains that are not already subject to these requirements.
- Update requirements in areas with a high risk of flooding to better manage tree and vegetation removal and require plantings that will preserve floodplain habitat.
- Add a requirement that development in floodplains within 170 ft of the Willamette River in the Central City improve floodplain habitat as a part of the proposal.
- Update floodplain mapping to incorporate the results of a recently completed model of flood risk along the Willamette River produced in collaboration with the U.S. Army Corps of Engineers.
Proposed amendments to the plan
The following amendments to the Recommended Draft will be considered by City Council at the August 30, 2023, hearing:
- Provide additional flexibility for projects that include more than one building and approved River Reviews. These amendments extend the expiration date for land use decisions for projects with multiple buildings and phased developments from 3 years to 7 years. The amendments also propose language to provide flexibility for minor changes to an approved River Review, allowing minor modifications as long as any additional development impacts are addressed.
- Allow for replacement of pump stations and other important utility infrastructure in the floodplain by (1) continuing to allow utilities located in the floodplain and in an Environmental overlay zone to be replaced without requiring City approval as long as the replacement does not expand the building footprint, and (2) allow existing pump stations located near the Willamette River to be replaced or expanded to meet existing and future demand, as long as the expansion does not move the pump station closer to the river.
- Clarify requirements for the modification of River Environmental overlay zone boundaries code section. These amendments ensure that the River Environmental overlay zone always includes (1) the riparian buffer area; (2) the area within 100 feet of top of bank in the Willamette River South Reach (as directed in the River Plan/South Reach); and (3) all undeveloped floodplains.
- Minor amendments to Chapter V and Chapter VI of the plan to update these sections to include more up-to-date information.
Effective date of proposed changes
Implementation of the zoning code (Title 33) changes is proposed to be phased, with a package of changes to go into effect in March of 2024 and a second package going into effect in October of 2025. Development projects that submit an application before the rules go into effect would be subject to the current floodplain regulations. Development projects submitted after the rules go into effect in fall 2025 would be subject to the updated protections.
The proposed implementation schedule for the zoning code changes is as follows:
October 2025 Effective Date
- Addition of the riparian buffer area map to the River Overlay Zones chapter (33.475) and resulting application of riparian buffer area requirements to floodplains within 170 feet of the Willamette River.
- Application of the expanded River Environmental overlay zone to encompass the riparian buffer area.
March 2024 Effective Date
- All other proposed changes, including amendments to the Environmental Zones (33.430) and Greenway Overlay Zone in the South Waterfront Subdistrict (33.510.253) chapters. The tree replacement standards added for the South Waterfront Subdistrict are consistent with requirements in the Willamette River Central Reach and South Reach.
- Addition of “combined flood hazard area” to 33.910.030, Definitions, and incorporation of the term into other zoning chapters where flood hazard areas are referenced.
This October 2025 implementation date for some of the proposed code changes is intended to align the City’s updated floodplain protections with the timeline for related updates to federal (FEMA) rules for floodplain protections (anticipated in early 2025). Adopting the regulations now and postponing their effective date provides stakeholders clarity and predictability on the City’s approach in floodplains and allows time to advance potential mitigation bank options.
Bureau of Development Services Chapter 24.50 Flood Hazard Areas Code Update Project
The Bureau of Development Services (BDS) is also bringing amendments to the City’s Building Regulations (Title 24) to City Council on August 30, 2023. Proposed updates to Chapter 24.50, Flood Hazard Areas, ensure flood storage is maintained when development occurs in the floodplain, reducing the risk of flooding on nearby properties. Find more information about the Title 24 project.
Upcoming engagement opportunities and schedule
Week of August 14 – Recommended Draft and amendments published
August 30, 2023 – City Council hearing
September/October 2023 – City Council deliberations, amendments and adoption
Testifying in person or virtually
The August 30 City Council hearing will be a hybrid meeting, and community members may testify in person, by phone, or video conference. Visit the City Council hearing event page to learn more about how to sign up to testify.
Testify in writing
Written testimony can be submitted using the Map App or vis U.S. Mail.
Map App
Go to the Floodplain Resilience Plan Map App, then click the "Testify" button.
U.S. Mail
Written testimony must be received by the time of the hearing and must include your name and address.
City Council Clerk
Floodplain Resilience Plan
1221 SW Fourth Avenue, Room 130
Portland, OR 97204