Updated March 1, 2023
DRAFT NATURAL HAZARDS MITIGATION PLAN UPDATE COMMENT PERIOD HAS ENDED
The Multnomah County Multi-Jurisdictional Natural Hazards Mitigation Plan (NHMP) is being updated. A draft of the plan is now available to review, and your comments are important. Feedback that is provided will be used to improve the final plan, and be maintained to continue to guide future updates. The period of comment for edits that can be made to this update have passed, but your comments are still appreciated and will be maintained for future updates. The draft update is now in the process of being finalized and submitted to Oregon Emergency Management for review. The updated draft will be posted here for continuing public review and comment. Thank you for your comments and support of this update!
Please provide any continuing comments on this survey form.
DRAFT PLAN UPDATE SECTIONS
- Draft NHMP - Section 1 - Introduction (584.21 KB)
- Draft NHMP - Section 2 - Community Profile (2.39 MB)
- Section 3 – Hazard Identification and Risk Assessment
- Draft NHMP - Section 3a - Earthquake (1.44 MB)
- Draft NHMP - Section 3b - Flood (1.68 MB)
- Draft NHMP - Section 3c - Landslide (1.87 MB)
- Draft NHMP - Section 3d - Severe Weather (845.58 KB)
- Draft NHMP - Section 3e - Volcano (1.12 MB)
- Draft NHMP - Section 3f - Wildfire and Wildfire Smoke (1.52 MB)
- Draft NHMP - Section 4 - Public Comment and Planning Process (571.19 KB)
- Section 5 – Jurisdictional Chapters
- Draft NHMP - Section 5a - City of Fairview (1.08 MB)
- Draft NHMP - Section 5b - City of Gresham (1.2 MB)
- Draft NHMP - Section 5c - City of Troutdale (1.1 MB)
- Draft NHMP - Section 5d - City of Wood Village (1.27 MB)
- Draft NHMP - Section 5e - Multnomah County (1.96 MB)
- Draft NHMP - Section 5f - Columbia Corridor Drainage Districts (1.39 MB)
- Draft NHMP - Section 5g - Port of Portland (1.63 MB)
The plan update draft and comment form are only available in English. Information about this update and natural hazards is available in: 中文(Chinese)| Русский (Russian)| Soomaali (Somali)| Español (Spanish)| Tiếng Việt (Vietnamese)
What is the Natural Hazards Mitigation Plan and why is it being updated?
Every five years, Multnomah County is required by the Federal Emergency Management Agency (FEMA) to update its Natural Hazards Mitigation Plan (NHMP). This plan uses the best available information about natural hazards to come up with actions to protect life, property and the environment in future natural disasters. The current plan was completed in 2017, and will be updated in 2023 by local adoption, after approval from FEMA and the Oregon Department of Emergency Management (OEM).
What is Hazard Mitigation?
Hazard mitigation is the work that is done before a disaster occurs, to lessen the severity of future natural disasters and make the community more resilient.
Successful hazard mitigation projects protect lives and property and also save the community money in the long run. It is estimated by FEMA that for every dollar spent on hazard mitigation, up to six dollars are saved when disasters strike.
What Hazards Are Covered in This Plan?
This plan only covers natural hazards; human-caused disasters such as terrorism and hazardous materials are covered in other plans. The State of Oregon lists natural hazards that have impacts across Oregon. Multnomah County communities plan for all of those except for coastal erosion and tsunami, which generally only damage coastal communities.
Multnomah County's hazard mitigation plan addresses the hazards listed below. The majority of these hazards are being impacted by climate change, and so it is more important than ever to prepare, because current information may underestimate the amount of risk we face.

- Increasing public awareness of risk and how to respond in an earthquake.
- Assisting residents gathering supplies in their homes to use after a severe earthquake.
- Supporting strengthening of bridges, levees, stone buildings, and other structures.

- Strengthening levees, dams, and floodwalls.
- Preserving floodplains as open space.
- Encouraging flood insurance to increase resilience of homes and businesses.

- Stabilizing slopes with trees and other vegetation.
- Limiting new construction in the highest hazard areas.
SEVERE WEATHER includes extreme heat, winter storms, wind storms, and drought. Unfortunately, all of these hazards are becoming more extreme and unpredictable due to climate change.

- Reducing urban heat effects by planting more trees.
- Advertising summer and winter shelter planning for those without climate-controlled living spaces.
- Promoting the use of anchors and tie-downs to protect manufactured homes in high winds.

- Publicizing community evacuation routes.
- Developing improved early warning systems.

- Assisting homeowners to create defensible space around homes and other structures.
- Removing invasive species to make forests more fire resistant.
- Upgrading air filtration in spaces that can be used as clean-air shelters.
To learn more about these hazards, go to Community Resources for Hazard Mitigation (English only). You can see maps of hazards at the following websites:
- HazVu - Oregon Department of Geology and Mineral Industries (DOGAMI) site shows earthquake, landslide, and volcano risk by address throughout Oregon. (In English)
- Oregon Wildfire Explorer - Oregon Department of Forestry (ODF) site shows wildfire risk by address throughout Oregon. (In English)
- National Flood Hazard Layer (NFHL) - Federal Emergency Management Agency (FEMA) website shows mapped flood risk by address across the United States. (In English)
- Metro Regional Barometer - Climate and Environment - Series of Metro Regional Government maps including Urban Heat Islands - locations where heat risk is the most severe. (In English)
Questions?
Contact David Lentzner, Planning Division - david.lentzner@multco.us or by phone at 503.679.3275.