FloodZoneMap.org

Multnomah County, Oregon Flood Zones

Check an Address in Multnomah County

Enter any address in Multnomah County, Oregon to see its FEMA flood zone

The Flooding Character of Multnomah County

River flooding is the dominant flood character in Multnomah County. Recent events include widespread river flooding in November 2021 due to an atmospheric river, and coastal, river, and urban flooding in January 2021, which also caused landslides and debris flows.

The National Flood Insurance Program data shows a significant number of claims in Zone A, with an average water depth of 7.0 feet and an average payout of $14,947. Zone X_SHADED also shows a high average payout of $30,097 with an average water depth of 5.4 feet, and Zone UNKNOWN has an average water depth of 6.9 feet.

Residents in low-lying areas, particularly those near rivers and creeks, should pay close attention to flood risk. Properties in Zone A, and those with unknown flood zone designations, may be particularly vulnerable to significant water depths and associated damages.

Summary generated from NOAA storm narratives and NFIP claim data for this county. Not predictive.

Read First-Hand Flood Stories from Multnomah County

1 NOAA storm reports from this county describe what happened, in the words of the meteorologists who were there.

Read Oregon flood stories →

Flood Risk Data for Multnomah County

Multnomah County, Oregon has recorded 15 flood-related events since 1996 according to NOAA's Storm Events Database, including 2 flash floods and 13 river or area floods. The county has received 12 federal disaster declarations, 4 of which involved flooding or coastal storms. Enter any address above to check its FEMA flood zone designation.

Multnomah County Disaster History

FEMA Disaster Declarations (1964–2024)

Disaster Declarations
12
Flood/Coastal Disasters
4
Latest Disaster
Severe Winter Storms, Straight-line Winds, Landslides, And Mudslides (2024-01-10)

Source: OpenFEMA Disaster Declarations Summaries.

Recent Disaster Declarations in Multnomah County

DeclarationTypeDate
Severe Winter Storms, Straight-line Winds, Landslides, And MudslidesSevere StormJan 10, 2024
Wildfires And Straight-line WindsFireSep 7, 2020
Covid-19BiologicalJan 20, 2020
Covid-19 PandemicBiologicalJan 20, 2020
Eagle Creek FireFireSep 2, 2017
Severe Winter Storms, Straight-line Winds, Flooding, Landslides, And MudslidesSevere StormDec 6, 2015
Severe Winter Storm, Record And Near Record SnowSevere StormDec 13, 2008
Hurricane Katrina EvacuationCoastal StormAug 29, 2005
Severe Winter StormsSevere StormDec 26, 2003
High Winds, Severe Storms And FloodingFloodFeb 4, 1996

Recorded Flood Events in Multnomah County

NOAA Storm Events Database (1996–2025)

Total Flood Events
15
River/Area Floods
13
Flash Floods
2
Total Property Damage
$13.0M

Source: NOAA National Weather Service Storm Events Database.

Recent Flood Events in Multnomah County

TypeDateDamage
FloodJun 11, 20220.00K
FloodJan 13, 20210.00K
FloodNov 12, 20210.00K
Flash FloodMay 4, 20170.00K
FloodDec 7, 20151087.00K
FloodSep 28, 201330.00K
FloodJan 19, 20120.00K
FloodNov 7, 20090.00K
FloodJan 2, 20090.00K
FloodDec 3, 20070.00K

Multnomah County Flood History

Flood — Jun 11, 2022

Heavy rains from an atmospheric river caused minor flooding and debris flow.

Flood — Jan 13, 2021

A series of slow moving fronts brought periods of heavy rain along with strong winds. This resulted in high surf; coastal, river and urban flooding; landslides; and debris flows. As the front moved inland early on the 13th, a debris flow resulted in a fatality in the Columbia River Gorge. The front brought a burst of 35-50 mph winds to the Willamette Valley and southwest Washington interior r...

Flood — Nov 12, 2021

Heavy rains produced by an atmospheric river brought river flooding to portions of northwest Oregon and southwest Washington. In addition, high tide backed up rivers and creeks in low lying areas along the coast, enhancing flooding.

Flash Flood — May 4, 2017

A strong upper-level trough generated enough instability for a few severe thunderstorms to develop across NW Oregon.

Flood — Dec 7, 2015

A moist pacific front produced heavy rainfall across Northwest Oregon which resulted in river flooding, urban flooding, small stream flooding, land slides, and a few sink holes.

Source: NOAA National Weather Service Storm Events Database.

Multnomah County NFIP Flood Insurance Claims

Total Claims Filed
290
Total Paid Out
$3.9M
Avg Claim
$19,818
Avg Water Depth
12.5 ft

Claims by Flood Zone

A Zones (High Risk)
121
X Shaded (500-yr)
30
X Unshaded (Low)
37

Source: OpenFEMA NFIP Individual Claims (2.25M records analyzed).

Flood Zone Types in Multnomah County

FEMA assigns flood zone designations to areas in Multnomah County, Oregon:

AE High Risk — 1% annual chance of flooding. Insurance required.

VE Very High Risk — Coastal flooding with wave action.

X (Shaded) Moderate Risk — 500-year floodplain.

X Low Risk — Outside major floodplains.

View all flood zone types →

Flood Insurance in Multnomah County

Properties in Multnomah County, Oregon that are in FEMA-designated Special Flood Hazard Areas (zones A and V) with federally backed mortgages are required to carry flood insurance.

Even outside high-risk zones, flood insurance is recommended. From 2014 to 2024, nearly one-third of NFIP claims came from outside the high-risk Special Flood Hazard Area.

Visit FloodSmart.gov to find an agent and get a quote.