Disaster-history hazard lens

Flood history by county

River, flash, coastal, and other flooding. Compare official county histories below while keeping FEMA administrative declarations separate from NOAA observed-event reports.

Data updated Aug 21, 2026 · Current conditions: Live Dashboard →

Administrative records

FEMA declaration history

Federal administrative declarations that include a county designation and map to this hazard category. A declaration is a government action, not a physical-event census.

47 counties have a positive flood count in this source.

Coverage: Jan 1, 1964 – Aug 21, 2026

Rankings compare only this source and exact coverage window. Equal counts share a rank.

Flood fema declaration history by county
Rank	County	Unique declarations
1	Cass County, North Dakota	22
2	King County, Washington	17
3	Harris County, Texas	12
4	Los Angeles County, California	10
4	Ventura County, California	10
4	East Baton Rouge Parish, Louisiana	10
4	St. Louis County, Missouri	10
4	Chittenden County, Vermont	10
4	Kanawha County, West Virginia	10
10	Maricopa County, Arizona	9
11	Pulaski County, Arkansas	8
11	Cook County, Illinois	8
11	Polk County, Iowa	8
11	Cumberland County, Maine	8
11	Milwaukee County, Wisconsin	8
16	El Paso County, Colorado	7
16	Hennepin County, Minnesota	7
16	Douglas County, Nebraska	7
19	Fresno County, California	6
19	Honolulu County, Hawaii	6
21	Middlesex County, Massachusetts	5
21	Wayne County, Michigan	5
21	Hillsborough County, New Hampshire	5
21	Bergen County, New Jersey	5
21	Philadelphia County, Pennsylvania	5
21	Minnehaha County, South Dakota	5
27	Jefferson County, Alabama	4
27	Jefferson County, Kentucky	4
27	Oklahoma County, Oklahoma	4
30	Marion County, Indiana	3
30	Montgomery County, Maryland	3
30	Kent County, Michigan	3
30	Kings County, New York	3
30	Multnomah County, Oregon	3
30	Salt Lake County, Utah	3
36	Hartford County, Connecticut	2
36	Ada County, Idaho	2
36	Johnson County, Kansas	2
36	Yellowstone County, Montana	2
36	Clark County, Nevada	2
36	Shelby County, Tennessee	2
42	Anchorage Municipality, Alaska	1
42	Harrison County, Mississippi	1
42	Franklin County, Ohio	1
42	Greenville County, South Carolina	1
42	Fairfax County, Virginia	1
42	Laramie County, Wyoming	1

Observed-event reports

NOAA observed-event history

Distinct NOAA Storm Events records explicitly coded to a county and mapped to this hazard category. Forecast-zone and marine-zone records are excluded from county totals.

53 counties have a positive flood count in this source.

Coverage: Jan 1, 1996 – May 31, 2026

Rankings compare only this source and exact coverage window. Equal counts share a rank.

Flood noaa observed-event history by county
Rank	County	County-event records
1	Maricopa County, Arizona	661
2	Fairfax County, Virginia	517
3	Montgomery County, Maryland	428
4	Cook County, Illinois	400
5	Clark County, Nevada	398
6	Bergen County, New Jersey	376
7	Fresno County, California	344
8	Wake County, North Carolina	289
9	Pulaski County, Arkansas	271
10	Polk County, Iowa	268
11	Los Angeles County, California	244
12	Honolulu County, Hawaii	229
13	New Castle County, Delaware	227
14	Harris County, Texas	226
15	Middlesex County, Massachusetts	225
15	Minnehaha County, South Dakota	225
17	Jefferson County, Kentucky	222
18	Philadelphia County, Pennsylvania	220
19	Shelby County, Tennessee	214
20	Oklahoma County, Oklahoma	209
21	El Paso County, Colorado	201
22	Kanawha County, West Virginia	193
23	Miami-Dade County, Florida	169
24	Jefferson County, Alabama	153
25	Franklin County, Ohio	147
26	Providence County, Rhode Island	146
27	Hartford County, Connecticut	145
28	Fulton County, Georgia	116
29	East Baton Rouge Parish, Louisiana	115
30	Greenville County, South Carolina	104
31	Marion County, Indiana	103
32	Johnson County, Kansas	99
33	Ventura County, California	97
33	Bernalillo County, New Mexico	97
35	Laramie County, Wyoming	92
36	Douglas County, Nebraska	87
37	Kings County, New York	83
38	Hillsborough County, New Hampshire	82
39	St. Louis County, Missouri	81
40	Harrison County, Mississippi	79
41	Cass County, North Dakota	74
42	Cumberland County, Maine	70
42	Milwaukee County, Wisconsin	70
44	Chittenden County, Vermont	60
45	Wayne County, Michigan	59
46	Hennepin County, Minnesota	54
47	Salt Lake County, Utah	43
48	Yellowstone County, Montana	37
49	Ada County, Idaho	23
50	Kent County, Michigan	22
51	Multnomah County, Oregon	13
52	King County, Washington	8
53	Anchorage Municipality, Alaska	1

How to interpret this hazard lens

Hazard categories normalize source labels into a shared taxonomy; source definitions and reporting practices still differ.
FEMA declarations reflect federal administrative actions and do not inventory every damaging local event.
NOAA totals include only distinct county-coded Storm Events records; forecast-zone and marine-zone records are excluded.
Only counties with a positive count for this category appear in each source table. Open a county profile for its complete source disclosures and preparedness context.