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This probabilistic forecast is issued by the Northwest River Forecast Center.

	Hydrograph			River at a Glance			Download			Probability Information Weekly Chance of Exceeding Levels Chance of Exceeding Levels During Entire Period Short-term Probabilistic Guidance (Experimental)

About this graph

Forecasts for the Siuslaw River near Mapleton are issued routinely year-round.

Return to Area Map

Zoom Level:16

Flood Categories (in feet)

Major Flood Stage:	28
Moderate Flood Stage:	22
Flood Stage:	18
Action Stage:	15
Low Stage (in feet):	-9999

Historic Crests
(1) 30.21 ft on 02/07/1996
(2) 28.45 ft on 01/21/1972
(3) 28.28 ft on 01/16/1974
(4) 28.07 ft on 01/19/2012
(5) 28.00 ft on 12/16/1964
Show More Historic Crests

(P): Preliminary values subject to further review.

Recent Crests
(1) 19.73 ft on 04/08/2019
(2) 22.36 ft on 12/18/2015
(3) 18.36 ft on 12/07/2015
(4) 22.80 ft on 12/21/2014
(5) 18.02 ft on 02/12/2014
Show More Recent Crests

(P): Preliminary values subject to further review.

Low Water Records
(1) 2.65 ft on 08/27/2015

	Gauge Location	Disclaimer
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

If you notice any errors in the below information, please contact our Webmaster
32.5	the flow at this level is about 62,000 cfs and has a 1 percent chance of happening in a given year (aka 100-year flood).
30.6	the flow at this level is about 56,000 cfs and has a 2 percent chance of happening in a given year (aka 50-year flood).
28	expect major flooding along Riverview Avenue area and numerous homes and businesses in Mapleton. Flooding of roads adjacent to the Siuslaw River in the vicinity of Mapleton is likely. Flooding of Highways 126 and 36 will be significant.
26	the flow at this level is 42,000 cfs and has a 10 percent chance of happening in a given year (aka 10-year flood).
25	expect widespread flooding, including several homes and structures in low areas of Mapleton. Many sections of Highway 126 from Tiernan to Mapleton, along with Hwy 36 north of Mapleton begin to flood. Flooding may be exacerbated during high tide.
23.2	the flow at this level is about 35,000 cfs and has a 20 percent chance of happening in a given year (aka 5-year flood).
22	expect widespread flooding of low-lying land. Several homes and structures in low areas of Mapleton start to flood. Numerous rural roads along and near the Siuslaw River will likely be flooded, and water begins to cover the lower sections of Hwy 126 at this stage. Flooding may be exacerbated during high tide.
20	expect water over East Mapleton Road. Flooding of some low-lying homes and structures begins. Flooding may be exacerbated by high tide.
19.1	The flow at this level is about 24,600 cfs and has an annual chance of 50 percent (aka 2-year flood).
18	expect minor flooding of low lying dairy land along with some structures right along the banks of the Siuslaw River in and near Mapleton.

Other Real-time and/or Archive Data Sources:

U.S. Geological Survey (USGS) Data and Site Info for Mapleton

Additional Information

10-day Forecast/Trend, Northwest River Forecast Center

Collaborative Agencies

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

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Page last modified: 2-Nov-2020 7:27 PM

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