Skip Navigation Link  
NOAA logo - Click to go to the NOAA homepage National Weather Service NWS logo - Click to go to the NWS homepage
Advanced Hydrologic Prediction Service
Image background of Navigation bar Left
Navigation Bar End Cap


This probabilistic forecast is issued by the Northwest River Forecast Center.
tab left off Hydrograph tab right off tab left off River at a Glance tab right off tab left off Download tab right off tab left on tab right on
About this graph
Forecasts for the Alsea River near Tidewater are issued routinely year-round.
Return to Area Map

Zoom Level:16
Flood Categories (in feet)
Major Flood Stage: 23
Moderate Flood Stage: 21
Flood Stage: 18
Action Stage: 16
Low Stage (in feet): -9999

Historic Crests
(1) 29.50 ft on 02/03/1890 (P)
(2) 27.44 ft on 12/22/1964
(3) 25.71 ft on 01/21/1972
(4) 24.55 ft on 01/16/1974
(5) 24.04 ft on 12/28/1998
Show More Historic Crests

(P): Preliminary values subject to further review.

Recent Crests
(1) 19.40 ft on 12/18/2015
(2) 18.89 ft on 12/21/2014
(3) 18.88 ft on 11/19/2012
(4) 23.61 ft on 01/19/2012
(5) 21.85 ft on 12/03/2007
Show More Recent Crests

(P): Preliminary values subject to further review.

Low Water Records
Currently none available.
KML Image
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
28.5 the flow is about 45,000 cfs and has a 1 percent chance of being exceeded in a given year (aka the 100-year flood).
27.2 the flow is about 41,000 cfs and has a 2 percent chance of being exceeded in any given year (aka the 50-year flood).
25.5 the flow is about 37,000 cfs and has a 4 percent chance of being exceeded in any give year (aka the 25-year flood).
24 expect flooding of numerous homes in the Little Albany area along with widespread flooding of numerous roads and structures along the river.
23 flooding begins at 'Alsea Riviera' and 'Little Albany' between Milepost 8 and 10 near Tidewater along State Hwy 34. Widespread lowland and pasture flooding will also continue. At this level, the flow is about 31,000 cfs and has a 10 percent chance of being exceeded in any given year (aka the 10-year flood).
21.5 the flow is about 27,000 cfs and has a 20 percent chance of being exceeded in a given year (aka 5-year flood).
21 expect widespread flooding along the Alsea. Flood waters will likely inundate property around homes and structures in communities along the Alsea, such as Tidewater, Alsea Riviera, Little Switzerland, and Little Albany. Erosion along the Alsea and tributary creeks may also cause localized damage.
20 water begins to surround houses at the 'Little Albany' community on Highway 34 near Milepost 8. Widespread pasture and dairy land flooding can be expected. Flooding of numerous roads along and near the river occurs at this level.
18 expect minor flooding of low-lying pasture land, roads, and a few structures close to the river. The flow
(1) USGS gage house
(2) Upstream view from USGS gage
(3) Downstream view from Thissell Rd Bridge just upstream of gage

Other Real-time and/or Archive Data Sources:

Additional Information Collapse
10-day Forecast/Trend, Northwest River Forecast Center
Collaborative Agencies Collapse
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
Portland Weather Forecast Office
5241 NE 122nd Avenue
Portland, OR 97230-1089
(503) 261-9246
Ask Questions/Webmaster
Page last modified: 2-Nov-2020 7:27 PM
Privacy Policy
About Us
Career Opportunities