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Weather Forecast Office Reno, NV

California Nevada River Forecast Center

Hydrograph

River at a Glance

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About this graph

Tabular Data (UTC)

Tabular Data (PDT)

Datum: NAVD88

Metadata

NOTE: Stage may be affected by ice during winter months.

NOTE: As of 10/1/2019 the vertical reference for observations and forecasts for this gage will be changed from a local reference to mean sea level. Additional details on this change can be found here or watch a 1 minute video here ***Note, all historic crests have been adjusted to the new datum and estimated based on CADWR rating #37 as of 11/23.

Reliability of the Forecast: Based on current and forecast river, weather and reservoir conditions

NOTE: Forecasts for the Middle Fork Feather River near Portola are issued routinely year-round.

Return to Area Map

Flood Categories (in feet)

Major Flood Stage:	4855.5
Moderate Flood Stage:	4853.5
Flood Stage:	4852.5
Action Stage:	4851
Low Stage (in feet):	-9999

Historic Crests
(1) 4,856.27 ft on 02/11/2017 (P)
(2) 4,854.42 ft on 03/16/2023 (P)
(3) 4,854.11 ft on 01/21/1969 (P)
(4) 4,853.58 ft on 03/27/1971 (P)
(5) 4,853.55 ft on 01/10/2017 (P)
Show More Historic Crests

(P): Preliminary values subject to further review.

Recent Crests
(1) 4,854.42 ft on 03/16/2023 (P)
(2) 4,853.06 ft on 03/01/2019 (P)
(3) 4,853.06 ft on 02/28/2019 (P)
(4) 4,853.32 ft on 03/24/2018 (P)
(5) 4,856.27 ft on 02/11/2017 (P)
Show More Recent Crests

(P): Preliminary values subject to further review.

Low Water Records
(1) 4,845.02 ft on 09/24/1976
(2) 4,845.02 ft on 10/01/1977
(3) 4,845.02 ft on 09/11/1969
(4) 4,845.03 ft on 09/15/1978
(5) 4,845.08 ft on 08/08/1973
Show More Low Water Records

For more information on your flood risk go to www.floodsmart.gov.

Show FEMA's National Flood Hazard Layers

Zoom Level:14

	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
4856.5	Major to near record flooding. Major damages to transportation, homes and businesses. Similar to January 1997, and in excess of February 9, 2017. Potential for rapid rises and major impacts from tributary streams. Tributary impacts may significantly proceed main-stem peak flows.
4855.5	Major Flood Stage. Major disruptions to transportation with significant impacts to homes and businesses between Beckworth and Clio. Approaching levels of February 9, 2017. Potential for rapid rises and major impacts from tributary streams. Impacts below Portola influenced by magnitude of tributary flows, especially Sulphur Creek. Tributary impacts may significantly proceed main-stem peak flows.
4854.5	Moderate flooding of businesses, homes, structures, and roads, including Highway 89 near Clio, portions of Highway 70, and low lying homes from Beckwourth to Clio. Impacts below Portola influenced by magnitude of tributary flows, especially Sulphur Creek.
4854	Moderate flooding of lowlands, roads, homes, businesses and structures along river from Beckwourth to Clio. Lowest homes on West Street begin to flood. Impacts below Portola influenced by magnitude of tributary flows, especially Sulphur Creek. Similar level to February 22nd, 2017, and slightly exceeding flooding of January 9, 2017.
4853.5	Moderate Flood Stage. Flooding of lowlands, structures, and roads from Beckwourth to Clio. Several low lying structures along river in Portola flood. Evacuation of homes on south end of West Street may be necessary. Highway 89 near Clio likely flooded. Impacts below Portola influenced by magnitude of tributary flows, especially Sulphur Creek. Similar level to 1/9/2017.
4853	Minor flooding of lowlands, roads, and low-lying structures between Beckwourth to Clio. In Portola the lowest lying buildings and businesses on highway 70 may begin to experience some minor flooding. Water along West Street nearing lowest homes along river. Highway 89 near Clio likely flooded. Potential for greater impacts in the lower portion of the reach with large contribution from tributary creeks. Similar level to 3/23/2018.
4852.5	Flood stage. Minor flooding of lowlands, rural roads, agricultural areas, and some low structures between Beckwourth and Clio. In Portola, water nearing lowest lying businesses along Highway 70 on west edge of Portola. The south end of West Street in Portola floods. Portions of Highway 89 near Clio may begin to flood. Potential for greater impacts in the lower portion of the reach with large contribution from tributary creeks. Similar level to March 17, 2011.
4852	Limited minor lowland flooding between Beckwourth and Clio. Potential for road impacts near Clio with large contribution from tributary creeks.
4851	Monitor Stage. Some areas of very minor out of bank flow between Beckwourth and Clio.
Photos (1) Upstream View From Gage Location above Portola on 17 March 2011. (2) Downstream View from Gage Location Above Portola on 17 March 2011 with a Stage of 9.0 Feet. (3) Upstream View from West Street on the Left Bank in Portola on 17 March 2011 at 9.0 Feet. (4) Upstream View From CA Hwy 89 below Clio Bridge on 17 March 2011.

About This Location

Latitude: 39.818889° N, Longitude: 120.445000° W, Horizontal Datum: NAD83/WGS84

River Stage Reference Frame	Gauge Height	Flood Stage	Uses
NWS stage	0 ft	4852.5 ft	Interpreting hydrographs and NWS watch, warnings, and forecasts, and inundation maps
Vertical Datum	Elevation (gauge height = 0)	Elevation (gauge height = flood stage)	Elevation information source
NAVD88	0.0	4852.5	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

Current/Historical Observations:

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

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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.

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

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