Latitude/Longitude Disclaimer: The gauge location shown in the above map is the approximate location based on the latitude/longitude coordinates provided to the NWS by the gauge owner.
Gauge Information
Map Overlays
FEMA's National Flood Hazard Layers not showing?
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There are no FEMA National Flood Hazard Layers for the location which you are viewing on ESRI Maps.
The FEMA Web Mapping Service (WMS) is down.
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Note: Your zoom level may have changed. ESRI's zoom levels must be between 14 and 16 to show National Flood Hazard layers.
Flood Categories (in KCFS)
Major Flood Flow:
15
Moderate Flood Flow:
11
Flood Flow:
7
Action Flow:
6.5
Low Stage (in feet):
-9999
Historic Crests
(1) 9,840 cfs on 06/13/1983
(2) 9,590 cfs on 06/06/2017
(3) 8,350 cfs on 05/31/1998
(4) 8,310 cfs on 05/05/2012
(5) 8,030 cfs on 06/07/1986
(6) 7,630 cfs on 06/29/1982
(7) 7,564 cfs on 06/06/1983
(8) 7,440 cfs on 04/30/2006 Show More Historic Crests
(P): Preliminary values subject to further review.
Recent Crests
(1) 7,340 cfs on 05/06/2019
(2) 6,520 cfs on 05/28/2018
(3) 9,590 cfs on 06/06/2017
(4) 6,420 cfs on 04/11/2016
(5) 1,770 cfs on 05/19/2015
(6) 2,040 cfs on 04/09/2014
(7) 1,520 cfs on 05/21/2013
(8) 8,310 cfs on 05/05/2012 Show More Recent Crests
(P): Preliminary values subject to further review.
Low Water Records (1) 42 cfs on 10/26/1983 (2) 109 cfs on 10/22/1985 (3) 110 cfs on 12/29/1988 Show More Low Water Records
Graphical representation of flood inundation for NWS flood categories are based on steady state hydraulic modeling of water surface elevations for incremented discharges. Map shows approximate inundation areas for given water surface elevations and should not be used for navigation or permitting or other legal purposes, but strictly as a planning reference tool.
Site-specific information: This interactive map depicts fifteen different flow rates of the Boise River from the head of Eagle Island to the Ada-Canyon County Line. The flow model used provides the best analysis of flooding and flood depths that it can. However, high water events are dynamic and flood waters could end up in areas not depicted on the map.
This map is for planning and awareness purposes only and is not the regulatory Flood Insurance Rate Map (FIRM). To check a property's flood designation, place the address in the search query box of the FEMA Flood map located online at: FEMA National Flood Hazard Map.
These inundation maps for the Boise River were developed by the U.S. Army Corps of Engineers in partnership with Ada County Emergency Management. The National Weather Service and U.S. Geological Survey provided technical expertise in the review and production of these maps.
Flood Impacts
If you notice any errors in the below information, please contact our Webmaster
16000
Major flooding will occur near the river in Boise, Garden City, Eagle, Star, and Caldwell. Some residential areas in low lying areas near the river will be flooded with water entering some houses. A flood of this magnitude has not occurred on the Boise River since 1943. Most of the area within the 100 year flood plain, including many city parks near the river, will be underwater. Debris piling up on bridge crossings will cause additional flood damage.
12000
Flooding will occur in low areas and parkland adjacent to the river in Boise, Garden City, Eagle, Star, and Caldwell. Flooding of low lying residential streets in areas adjacent to the river is likely, especially on portions of Eagle Island. Debris damming on bridges crossing the river will occur and may cause water to spill over the road surfaces leading up to the bridge.
10500
Flooding near the river will occur in low areas of Boise, Garden City, Eagle, Star and Caldwell. Portions of Eagle Island will be submerged with flooding of residential property in low lying areas near the river likely. The water should remain below the level of most residential structures, but access in and out of some neighborhoods may be limited by high water.
9500
Flooding of low areas near the river in Boise, Garden City, Eagle, Star, and Caldwell will occur. Debris in the river will collect on bridges crossing the river. The water may affect some residential property near the river, but should stay below the level of most residential structures.
8900
Large sections of the green belt will be submerged and severe bank erosion will occur. Flooding will occur in low areas close to the river in Boise, Garden City, Eagle and Caldwell, but the water should remain below the level of most residential areas.
8200
Large sections of the green belt will be submerged and severe bank erosion will occur. Flooding will occur in low areas close to the river in Boise, Garden City, Eagle and Caldwell, but the water should remain below the level of most residential areas. Water will begin seeping into the Garden City warehouse district between 45th and 47th streets.
7000
Large sections of the greenbelt path adjacent to the river will be submerged. Erosion of river banks will also become a significant problem. Debris in the river including small trees and logs may begin piling up at bridge crossings. Minor flooding will be observed on sections of Eagle Island and in other low spots near the river. Minor flooding will spread downstream to low areas near the river in Star and Caldwell.
6500
Large sections of the greenbelt path adjacent to the river will be submerged. Minor flooding may affect portions of Eagle Island.
4000
Water will begin seeping onto low spots on the greenbelt path next to the river especially near bridge underpasses. Minor out or bank flow may begin to impact portions of Eagle Island along the south channel.
Additional Information
This is a pseudo gage being used as a place- holder for flood inundation maps on the Boise River for the river reach from the head of Eagle Island to the Ada-Canyon County line. Data from upstream gage BIGI1 is being used to populate observed and forecast data, flood flows and impacts, and historical crest information.
The National Weather Service prepares its forecasts and other services in collaboration with agencies like the US Geological Survey, US Bureau of Reclamation, US Army Corps of Engineers, Natural Resource Conservation Service, National Park Service, ALERT Users Group, Bureau of Indian Affairs, and many state and local emergency managers across the country. For details, please click here.
Graphical representation of flood inundation for NWS flood categories are based on steady state hydraulic modeling of water surface elevations for incremented discharges. Map shows approximate inundation areas for given water surface elevations and should not be used for navigation or permitting or other legal purposes, but strictly as a planning reference tool.
