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Hydrograph River at a Glance Download
Fortymile River at West Fork Stage (ft)Observed: 6.15 ft at 2:26PM Mar 25, 2023Observed: 6.31 ft at 6:02PM Mar 25, 2023Observed: 6.23 ft at 12:02AM Mar 26, 2023Observed: 6.31 ft at 8:26AM Mar 26, 2023Observed: 6.3 ft at 12:02PM Mar 26, 2023Observed: 6.21 ft at 6:02PM Mar 26, 2023Observed: 6.39 ft at 6:02PM Mar 27, 2023Observed: 6.21 ft at 12:02AM Mar 28, 2023Highest Observation: 6.62 ft at 6:03AM Mar 28, 2023Observed: 6.35 ft at 12:02PM Mar 28, 2023Observed: 6.37 ft at 6:38PM Mar 28, 2023Observed: 6.27 ft at 12:02AM Mar 29, 2023Observed: 6.29 ft at 6:03AM Mar 29, 2023Observed: 6.14 ft at 12:39PM Mar 29, 2023Observed: 6.2 ft at 6:02PM Mar 29, 2023Observed: 6.26 ft at 12:02AM Mar 30, 2023Observed: 6.46 ft at 6:38AM Mar 30, 2023Observed: 6.21 ft at 6:02PM Mar 30, 2023Observed: 6.29 ft at 12:02AM Mar 31, 2023Observed: 6.22 ft at 12:03AM Apr 01, 2023FMWA2(plotting HGIRZ) Graph Created (1:02PM Apr 1, 2023)ObservedLatest observed value: 6.22 ft at 12:03 AM AKDT 1-Apr-2023. Flood Stage is 21 ft
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About this graph
Tabular Data (UTC)
Tabular Data (AKDT)
XML Data
RSS Files
Datum: Not Available
NOTE: NWS gage operated on a seasonal basis. No data available during winter months.

NOTE: Gage data do not meet the quality standards of USGS gages.

NOTE: Forecasts are not available for the Fortymile River at West Fork. Only observed stages are available for this point.

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Upstream Gauge - at Mosquito Fork Upstream Gauge Downstream Gauge Downstream Gauge - at South Fork
Flood Categories (in feet)
Major Flood Stage: 0
Moderate Flood Stage: 0
Flood Stage: 21
Action Stage: 12
Low Stage (in feet): -9999

Historic Crests

(P): Preliminary values subject to further review.

Recent Crests

(P): Preliminary values subject to further review.

Low Water Records
Currently none available.
Zoom Level:6
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Gauge LocationGauge Map Marker
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.
Flood Impacts & Photos Collapse
If you notice any errors in the below information, please contact our Webmaster
21 low spot in approach from the south to the bridge near the campground becomes flooded.
12 bankfull stage.
(1) Bridge
(2) Downstream
(3) Upstream
(4) Fortymile River at West Fork looking downstream, Stage = 7.15 ft
About This Location Collapse

Latitude: 63.889444° N, Longitude: 142.232222° W, Horizontal Datum: NAD83/WGS84

River Stage
Reference Frame
Gauge Height Flood Stage Uses
NWS stage 0 ft 21 ft Interpreting hydrographs and NWS watch, warnings, and forecasts, and inundation maps
Vertical Datum Elevation
(gauge height = 0)
(gauge height = flood stage)
Elevation information source
NAVD88 1828.59 ft 1849.59 ft Survey grade GPS equipment, FEMA flood plain maps, newer USGS topographic maps
NGVD 29 Not Available Not Available Older USGS topographic maps, NGVD29 benchmarks
MSL Not Available Not Available Older USGS topographic maps, MSL benchmarks
Other Not Available Not Available  
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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.
NWS Information
National Weather Service
Fairbanks Weather Forecast Office
UAF-IARC Bldg. P.O. Box 757345
Fairbanks, AK 99775-7345
(907) 458-3700
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Page last modified: 2-Nov-2020 7:26 PM
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