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Hydrograph River at a Glance Download
Allegheny River at Olean Stage (ft)Flow (kcfs)Highest Observation: 11.11 ft at 3:15AM Apr 15, 2024Observed: 11.1 ft at 3:30AM Apr 15, 2024Observed: 11.1 ft at 3:31AM Apr 15, 2024Observed: 11.06 ft at 3:45AM Apr 15, 2024Observed: 11.06 ft at 3:46AM Apr 15, 2024Observed: 11.07 ft at 4:00AM Apr 15, 2024Observed: 11.04 ft at 4:15AM Apr 15, 2024Observed: 11.03 ft at 4:30AM Apr 15, 2024Observed: 11.03 ft at 4:31AM Apr 15, 2024Observed: 11 ft at 4:45AM Apr 15, 2024Observed: 11 ft at 4:46AM Apr 15, 2024Observed: 11 ft at 5:00AM Apr 15, 2024Observed: 10.97 ft at 5:15AM Apr 15, 2024Observed: 10.95 ft at 5:30AM Apr 15, 2024Observed: 10.95 ft at 5:31AM Apr 15, 2024Observed: 10.95 ft at 5:45AM Apr 15, 2024Observed: 10.95 ft at 5:46AM Apr 15, 2024Observed: 10.92 ft at 6:00AM Apr 15, 2024Observed: 10.92 ft at 6:01AM Apr 15, 2024Observed: 10.92 ft at 6:15AM Apr 15, 2024Observed: 10.92 ft at 6:16AM Apr 15, 2024Observed: 10.88 ft at 6:30AM Apr 15, 2024Observed: 10.86 ft at 6:45AM Apr 15, 2024Observed: 10.84 ft at 7:00AM Apr 15, 2024Observed: 10.84 ft at 7:01AM Apr 15, 2024Observed: 10.83 ft at 7:15AM Apr 15, 2024Observed: 10.83 ft at 7:16AM Apr 15, 2024Observed: 10.8 ft at 7:30AM Apr 15, 2024Observed: 10.8 ft at 7:31AM Apr 15, 2024Observed: 10.79 ft at 7:45AM Apr 15, 2024Observed: 10.79 ft at 7:46AM Apr 15, 2024Observed: 10.78 ft at 8:00AM Apr 15, 2024Observed: 10.74 ft at 8:15AM Apr 15, 2024Observed: 10.74 ft at 8:16AM Apr 15, 2024Observed: 10.73 ft at 8:30AM Apr 15, 2024Observed: 10.73 ft at 8:31AM Apr 15, 2024Observed: 10.7 ft at 8:45AM Apr 15, 2024Observed: 10.7 ft at 8:46AM Apr 15, 2024Observed: 10.69 ft at 9:00AM Apr 15, 2024Observed: 10.66 ft at 9:15AM Apr 15, 2024Observed: 10.66 ft at 9:16AM Apr 15, 2024Observed: 10.66 ft at 9:30AM Apr 15, 2024Observed: 10.66 ft at 9:31AM Apr 15, 2024Observed: 10.63 ft at 9:45AM Apr 15, 2024Observed: 10.63 ft at 9:46AM Apr 15, 2024Observed: 10.61 ft at 10:00AM Apr 15, 2024Observed: 10.6 ft at 10:15AM Apr 15, 2024Observed: 10.6 ft at 10:16AM Apr 15, 2024Observed: 10.58 ft at 10:30AM Apr 15, 2024Observed: 10.58 ft at 10:31AM Apr 15, 2024Observed: 10.54 ft at 10:45AM Apr 15, 2024Observed: 10.54 ft at 10:46AM Apr 15, 2024Observed: 10.54 ft at 11:00AM Apr 15, 2024Observed: 10.52 ft at 11:15AM Apr 15, 2024Observed: 10.5 ft at 11:30AM Apr 15, 2024Observed: 10.5 ft at 11:31AM Apr 15, 2024Observed: 10.48 ft at 11:45AM Apr 15, 2024Observed: 10.45 ft at 12:00PM Apr 15, 2024Observed: 10.45 ft at 12:01PM Apr 15, 2024Observed: 10.44 ft at 12:15PM Apr 15, 2024Observed: 10.44 ft at 12:16PM Apr 15, 2024Observed: 10.43 ft at 12:30PM Apr 15, 2024Observed: 10.4 ft at 12:45PM Apr 15, 2024Observed: 10.4 ft at 12:46PM Apr 15, 2024Observed: 10.4 ft at 1:00PM Apr 15, 2024Observed: 10.4 ft at 1:01PM Apr 15, 2024Observed: 10.37 ft at 1:15PM Apr 15, 2024Observed: 10.37 ft at 1:16PM Apr 15, 2024Observed: 10.34 ft at 1:30PM Apr 15, 2024Observed: 10.3 ft at 1:45PM Apr 15, 2024Observed: 10.31 ft at 2:00PM Apr 15, 2024Observed: 10.32 ft at 2:15PM Apr 15, 2024Observed: 10.32 ft at 2:16PM Apr 15, 2024Observed: 10.27 ft at 2:30PM Apr 15, 2024Observed: 10.25 ft at 2:45PM Apr 15, 2024Observed: 10.25 ft at 2:46PM Apr 15, 2024Observed: 10.24 ft at 3:00PM Apr 15, 2024Observed: 10.24 ft at 3:01PM Apr 15, 2024Observed: 10.2 ft at 3:15PM Apr 15, 2024Observed: 10.19 ft at 3:30PM Apr 15, 2024Observed: 10.19 ft at 3:31PM Apr 15, 2024Observed: 10.16 ft at 3:45PM Apr 15, 2024Observed: 10.16 ft at 3:46PM Apr 15, 2024Observed: 10.16 ft at 4:00PM Apr 15, 2024Observed: 10.16 ft at 4:01PM Apr 15, 2024Observed: 10.14 ft at 4:15PM Apr 15, 2024Observed: 10.14 ft at 4:16PM Apr 15, 2024Observed: 10.13 ft at 4:30PM Apr 15, 2024Observed: 10.13 ft at 4:31PM Apr 15, 2024Observed: 10.09 ft at 4:45PM Apr 15, 2024Observed: 10.1 ft at 5:00PM Apr 15, 2024Observed: 10.07 ft at 5:15PM Apr 15, 2024Observed: 10.07 ft at 5:16PM Apr 15, 2024Observed: 10.05 ft at 5:30PM Apr 15, 2024Observed: 10.05 ft at 5:31PM Apr 15, 2024Observed: 10.02 ft at 5:45PM Apr 15, 2024Observed: 10 ft at 6:00PM Apr 15, 2024Observed: 10 ft at 6:01PM Apr 15, 2024Observed: 9.99 ft at 6:15PM Apr 15, 2024Observed: 9.99 ft at 6:16PM Apr 15, 2024Observed: 9.97 ft at 6:30PM Apr 15, 2024Observed: 9.97 ft at 6:45PM Apr 15, 2024Observed: 9.97 ft at 6:46PM Apr 15, 2024Observed: 9.94 ft at 7:00PM Apr 15, 2024Observed: 9.91 ft at 7:15PM Apr 15, 2024Observed: 9.89 ft at 7:30PM Apr 15, 2024Observed: 9.87 ft at 7:45PM Apr 15, 2024Observed: 9.86 ft at 8:00PM Apr 15, 2024Observed: 9.83 ft at 8:15PM Apr 15, 2024Observed: 9.81 ft at 8:30PM Apr 15, 2024Observed: 9.8 ft at 8:45PM Apr 15, 2024Observed: 9.78 ft at 9:00PM Apr 15, 2024Observed: 9.76 ft at 9:15PM Apr 15, 2024Observed: 9.74 ft at 9:30PM Apr 15, 2024Observed: 9.72 ft at 9:45PM Apr 15, 2024Observed: 9.71 ft at 10:00PM Apr 15, 2024Observed: 9.68 ft at 10:15PM Apr 15, 2024Observed: 9.66 ft at 10:30PM Apr 15, 2024Observed: 9.63 ft at 10:45PM Apr 15, 2024Observed: 9.62 ft at 11:00PM Apr 15, 2024Observed: 9.61 ft at 11:15PM Apr 15, 2024Observed: 9.58 ft at 11:30PM Apr 15, 2024Observed: 9.56 ft at 11:45PM Apr 15, 2024Observed: 9.54 ft at 12:00AM Apr 16, 2024Observed: 9.52 ft at 12:15AM Apr 16, 2024Observed: 9.5 ft at 12:30AM Apr 16, 2024Observed: 9.49 ft at 12:45AM Apr 16, 2024Observed: 9.46 ft at 1:00AM Apr 16, 2024Observed: 9.45 ft at 1:15AM Apr 16, 2024Observed: 9.42 ft at 1:30AM Apr 16, 2024Observed: 9.4 ft at 1:45AM Apr 16, 2024Observed: 9.4 ft at 2:00AM Apr 16, 2024Observed: 9.36 ft at 2:15AM Apr 16, 2024Observed: 9.36 ft at 2:30AM Apr 16, 2024Observed: 9.34 ft at 2:45AM Apr 16, 2024Observed: 9.33 ft at 3:00AM Apr 16, 2024Observed: 9.3 ft at 3:15AM Apr 16, 2024Observed: 9.28 ft at 3:30AM Apr 16, 2024Observed: 9.26 ft at 3:45AM Apr 16, 2024Observed: 9.25 ft at 4:00AM Apr 16, 2024Observed: 9.23 ft at 4:15AM Apr 16, 2024Observed: 9.2 ft at 4:30AM Apr 16, 2024Observed: 9.18 ft at 4:45AM Apr 16, 2024Observed: 9.18 ft at 5:00AM Apr 16, 2024Observed: 9.15 ft at 5:15AM Apr 16, 2024Observed: 9.14 ft at 5:30AM Apr 16, 2024Observed: 9.13 ft at 5:45AM Apr 16, 2024Observed: 9.1 ft at 6:00AM Apr 16, 2024Observed: 9.09 ft at 6:15AM Apr 16, 2024Observed: 9.08 ft at 6:30AM Apr 16, 2024Observed: 8.99 ft at 7:45AM Apr 16, 2024Observed: 8.97 ft at 8:00AM Apr 16, 2024Observed: 8.95 ft at 8:15AM Apr 16, 2024Observed: 8.94 ft at 8:30AM Apr 16, 2024Observed: 8.93 ft at 8:45AM Apr 16, 2024Observed: 8.9 ft at 9:00AM Apr 16, 2024Observed: 8.89 ft at 9:15AM Apr 16, 2024Observed: 8.87 ft at 9:30AM Apr 16, 2024Observed: 8.86 ft at 9:45AM Apr 16, 2024Observed: 8.85 ft at 10:00AM Apr 16, 2024Observed: 8.82 ft at 10:15AM Apr 16, 2024Observed: 8.82 ft at 10:30AM Apr 16, 2024Observed: 8.79 ft at 10:45AM Apr 16, 2024Observed: 8.78 ft at 11:00AM Apr 16, 2024Observed: 8.75 ft at 11:15AM Apr 16, 2024Observed: 8.75 ft at 11:30AM Apr 16, 2024Observed: 8.74 ft at 11:45AM Apr 16, 2024Observed: 8.72 ft at 12:00PM Apr 16, 2024Observed: 8.7 ft at 12:15PM Apr 16, 2024Observed: 8.68 ft at 12:30PM Apr 16, 2024Observed: 8.66 ft at 12:45PM Apr 16, 2024Observed: 8.64 ft at 1:00PM Apr 16, 2024Observed: 8.63 ft at 1:15PM Apr 16, 2024Observed: 8.62 ft at 1:30PM Apr 16, 2024Observed: 8.59 ft at 1:45PM Apr 16, 2024Observed: 8.57 ft at 2:00PM Apr 16, 2024Observed: 8.56 ft at 2:15PM Apr 16, 2024Observed: 8.55 ft at 2:30PM Apr 16, 2024Observed: 8.54 ft at 2:45PM Apr 16, 2024Observed: 8.5 ft at 3:00PM Apr 16, 2024Observed: 8.48 ft at 3:15PM Apr 16, 2024Observed: 8.47 ft at 3:30PM Apr 16, 2024Observed: 8.46 ft at 3:45PM Apr 16, 2024Observed: 8.44 ft at 4:00PM Apr 16, 2024Observed: 8.42 ft at 4:15PM Apr 16, 2024Observed: 8.39 ft at 4:30PM Apr 16, 2024Observed: 8.38 ft at 4:45PM Apr 16, 2024Observed: 8.36 ft at 5:00PM Apr 16, 2024Observed: 8.34 ft at 5:15PM Apr 16, 2024Observed: 8.31 ft at 5:30PM Apr 16, 2024Observed: 8.29 ft at 5:45PM Apr 16, 2024Observed: 8.27 ft at 6:00PM Apr 16, 2024Observed: 8.24 ft at 6:15PM Apr 16, 2024Observed: 8.22 ft at 6:30PM Apr 16, 2024Observed: 8.21 ft at 6:45PM Apr 16, 2024Observed: 8.19 ft at 7:00PM Apr 16, 2024Observed: 8.18 ft at 7:15PM Apr 16, 2024Observed: 8.15 ft at 7:30PM Apr 16, 2024Observed: 8.12 ft at 7:45PM Apr 16, 2024Observed: 8.09 ft at 8:00PM Apr 16, 2024Observed: 8.08 ft at 8:15PM Apr 16, 2024Observed: 8.06 ft at 8:30PM Apr 16, 2024Observed: 8.04 ft at 8:45PM Apr 16, 2024Observed: 8.01 ft at 9:00PM Apr 16, 2024Observed: 7.99 ft at 9:15PM Apr 16, 2024Observed: 7.98 ft at 9:30PM Apr 16, 2024Observed: 7.95 ft at 9:45PM Apr 16, 2024Observed: 7.94 ft at 10:00PM Apr 16, 2024Observed: 7.92 ft at 10:15PM Apr 16, 2024Observed: 7.9 ft at 10:30PM Apr 16, 2024Observed: 7.88 ft at 10:45PM Apr 16, 2024Observed: 7.86 ft at 11:00PM Apr 16, 2024Observed: 7.84 ft at 11:15PM Apr 16, 2024Observed: 7.82 ft at 11:30PM Apr 16, 2024Observed: 7.81 ft at 11:45PM Apr 16, 2024Observed: 7.79 ft at 12:00AM Apr 17, 2024Observed: 7.77 ft at 12:15AM Apr 17, 2024Observed: 7.75 ft at 12:30AM Apr 17, 2024Observed: 7.73 ft at 12:45AM Apr 17, 2024Observed: 7.71 ft at 1:00AM Apr 17, 2024Observed: 7.69 ft at 1:15AM Apr 17, 2024Observed: 7.65 ft at 1:30AM Apr 17, 2024Observed: 7.64 ft at 1:45AM Apr 17, 2024Observed: 7.63 ft at 2:00AM Apr 17, 2024Observed: 7.61 ft at 2:15AM Apr 17, 2024Observed: 7.59 ft at 2:30AM Apr 17, 2024Observed: 7.57 ft at 2:45AM Apr 17, 2024Observed: 7.55 ft at 3:00AM Apr 17, 2024Observed: 7.53 ft at 3:15AM Apr 17, 2024Observed: 7.52 ft at 3:30AM Apr 17, 2024Observed: 7.49 ft at 3:45AM Apr 17, 2024Observed: 7.47 ft at 4:00AM Apr 17, 2024Observed: 7.46 ft at 4:15AM Apr 17, 2024Observed: 7.43 ft at 4:30AM Apr 17, 2024Observed: 7.41 ft at 4:45AM Apr 17, 2024Observed: 7.4 ft at 5:00AM Apr 17, 2024Observed: 7.38 ft at 5:15AM Apr 17, 2024Observed: 7.36 ft at 5:30AM Apr 17, 2024Observed: 7.34 ft at 5:45AM Apr 17, 2024Observed: 7.32 ft at 6:00AM Apr 17, 2024Observed: 7.3 ft at 6:15AM Apr 17, 2024Observed: 7.28 ft at 6:30AM Apr 17, 2024Observed: 7.27 ft at 6:45AM Apr 17, 2024Observed: 7.24 ft at 7:00AM Apr 17, 2024Observed: 7.24 ft at 7:15AM Apr 17, 2024Observed: 7.21 ft at 7:30AM Apr 17, 2024Observed: 7.2 ft at 7:45AM Apr 17, 2024Observed: 7.17 ft at 8:00AM Apr 17, 2024Observed: 7.16 ft at 8:15AM Apr 17, 2024Observed: 7.14 ft at 8:30AM Apr 17, 2024Observed: 7.12 ft at 8:45AM Apr 17, 2024Observed: 7.1 ft at 9:00AM Apr 17, 2024Observed: 7.09 ft at 9:15AM Apr 17, 2024Observed: 7.07 ft at 9:30AM Apr 17, 2024Observed: 7.04 ft at 9:45AM Apr 17, 2024Observed: 7.02 ft at 10:00AM Apr 17, 2024Observed: 7.01 ft at 10:15AM Apr 17, 2024Observed: 6.99 ft at 10:30AM Apr 17, 2024Observed: 6.98 ft at 10:45AM Apr 17, 2024Observed: 6.96 ft at 11:00AM Apr 17, 2024Observed: 6.94 ft at 11:15AM Apr 17, 2024Observed: 6.92 ft at 11:30AM Apr 17, 2024Observed: 6.91 ft at 11:45AM Apr 17, 2024Observed: 6.9 ft at 12:00PM Apr 17, 2024Observed: 6.88 ft at 12:15PM Apr 17, 2024Observed: 6.86 ft at 12:30PM Apr 17, 2024Observed: 6.83 ft at 12:45PM Apr 17, 2024Observed: 6.83 ft at 1:00PM Apr 17, 2024Observed: 6.81 ft at 1:15PM Apr 17, 2024Observed: 6.79 ft at 1:30PM Apr 17, 2024Observed: 6.78 ft at 1:45PM Apr 17, 2024Observed: 6.77 ft at 2:00PM Apr 17, 2024Observed: 6.74 ft at 2:15PM Apr 17, 2024Observed: 6.72 ft at 2:30PM Apr 17, 2024Observed: 6.71 ft at 2:45PM Apr 17, 2024Observed: 6.7 ft at 3:00PM Apr 17, 2024Observed: 6.68 ft at 3:15PM Apr 17, 2024Observed: 6.67 ft at 3:30PM Apr 17, 2024Observed: 6.66 ft at 3:45PM Apr 17, 2024Observed: 6.64 ft at 4:00PM Apr 17, 2024Observed: 6.62 ft at 4:15PM Apr 17, 2024Observed: 6.6 ft at 4:30PM Apr 17, 2024Observed: 6.59 ft at 4:45PM Apr 17, 2024Observed: 6.58 ft at 5:00PM Apr 17, 2024Observed: 6.57 ft at 5:15PM Apr 17, 2024Observed: 6.55 ft at 5:30PM Apr 17, 2024Observed: 6.53 ft at 5:45PM Apr 17, 2024Observed: 6.53 ft at 6:00PM Apr 17, 2024Observed: 6.51 ft at 6:15PM Apr 17, 2024Observed: 6.5 ft at 6:30PM Apr 17, 2024Observed: 6.48 ft at 6:45PM Apr 17, 2024Observed: 6.48 ft at 6:46PM Apr 17, 2024Observed: 6.46 ft at 7:00PM Apr 17, 2024Observed: 6.46 ft at 7:15PM Apr 17, 2024Observed: 6.44 ft at 7:30PM Apr 17, 2024Observed: 6.44 ft at 7:45PM Apr 17, 2024Observed: 6.42 ft at 8:00PM Apr 17, 2024Observed: 6.41 ft at 8:15PM Apr 17, 2024Observed: 6.41 ft at 8:30PM Apr 17, 2024Observed: 6.39 ft at 8:45PM Apr 17, 2024Observed: 6.38 ft at 9:00PM Apr 17, 2024Observed: 6.37 ft at 9:15PM Apr 17, 2024Observed: 6.36 ft at 9:30PM Apr 17, 2024Observed: 6.35 ft at 9:45PM Apr 17, 2024Observed: 6.34 ft at 10:00PM Apr 17, 2024Observed: 6.34 ft at 10:15PM Apr 17, 2024Observed: 6.35 ft at 10:30PM Apr 17, 2024Observed: 6.34 ft at 10:45PM Apr 17, 2024Observed: 6.34 ft at 11:00PM Apr 17, 2024Observed: 6.33 ft at 11:15PM Apr 17, 2024Observed: 6.33 ft at 11:30PM Apr 17, 2024Observed: 6.32 ft at 11:45PM Apr 17, 2024Observed: 6.31 ft at 12:00AM Apr 18, 2024Observed: 6.31 ft at 12:15AM Apr 18, 2024Observed: 6.3 ft at 12:30AM Apr 18, 2024Observed: 6.31 ft at 12:45AM Apr 18, 2024Observed: 6.31 ft at 1:00AM Apr 18, 2024Observed: 6.31 ft at 1:15AM Apr 18, 2024Observed: 6.32 ft at 1:30AM Apr 18, 2024Observed: 6.32 ft at 1:45AM Apr 18, 2024Observed: 6.33 ft at 2:00AM Apr 18, 2024Observed: 6.34 ft at 2:15AM Apr 18, 2024Observed: 6.35 ft at 2:30AM Apr 18, 2024Forecast: 6.4 ft 8:00AM Apr 18, 2024Forecast: 6.4 ft 2:00PM Apr 18, 2024Highest Forecast: 6.5 ft 8:00PM Apr 18, 2024Highest Forecast: 6.5 ft 2:00AM Apr 19, 2024Forecast: 6.4 ft 8:00AM Apr 19, 2024Forecast: 6.3 ft 2:00PM Apr 19, 2024Forecast: 6.1 ft 8:00PM Apr 19, 2024Forecast: 5.9 ft 2:00AM Apr 20, 2024Forecast: 5.7 ft 8:00AM Apr 20, 2024Forecast: 5.5 ft 2:00PM Apr 20, 2024Forecast: 5.3 ft 8:00PM Apr 20, 2024Forecast: 5.1 ft 2:00AM Apr 21, 2024Forecast: 5 ft 8:00AM Apr 21, 2024Forecast: 4.8 ft 2:00PM Apr 21, 2024Forecast: 4.7 ft 8:00PM Apr 21, 2024Forecast: 4.5 ft 2:00AM Apr 22, 2024Forecast: 4.4 ft 8:00AM Apr 22, 2024OLNN6(plotting HGIRG) Graph Created (3:01AM Apr 18, 2024)ObservedForecast (issued 8:58AM Apr 17)Latest observed value: 6.35 ft at 2:30 AM EDT 18-Apr-2024. Flood Stage is 12 ft
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About this graph
Tabular Data (UTC)
Tabular Data (EDT)
XML Data
RSS Files
Datum: NAVD88
Metadata
NOTE: Forecasts for the Allegheny River at Olean are issued routinely year-round.
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Upstream Locations Upstream Gauge Downstream Gauge Downstream Gauge - at Salamanca
Flood Categories (in feet)
Major Flood Stage: 23
Moderate Flood Stage: 17
Flood Stage: 12
Action Stage: 10
Low Stage (in feet): -9999

Historic Crests
(1) 26.20 ft on 06/23/1972
(2) 23.30 ft on 07/19/1942
(3) 19.50 ft on 03/08/1956
(4) 19.30 ft on 05/29/1946
(5) 18.60 ft on 01/20/1996
Show More Historic Crests

(P): Preliminary values subject to further review.

Recent Crests
(1) 13.33 ft on 02/19/2022
(2) 13.91 ft on 01/14/2018
(3) 14.17 ft on 01/13/2017
(4) 17.74 ft on 12/03/2010
(5) 12.34 ft on 03/11/2009
Show More Recent Crests

(P): Preliminary values subject to further review.

Low Water Records
(1) 0.50 ft on 08/03/1999
(2) 1.00 ft on 09/01/1998
(3) 1.15 ft on 08/10/2016
Zoom Level:16
KML Image
Gauge LocationGauge Map Marker
 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 Collapse
If you notice any errors in the below information, please contact our Webmaster
25 Extreme flood, extensive residential flooding begins, especially upstream from Union Street bridge. Some evacuations necessary. Serious flooding upstream through Portville. Dikes overwhelmed.
23 Major flood, protective dikes begin to be topped. Some roadway flooding in residential areas of city begins, especially upstream. Serious flooding in areas unprotected by dikes including portions of Portville.
17 Moderate flood, water affects Riverview School of Aviation, 1.5 miles upstream of Union Street bridge. Local flooding occurs in areas unprotected by dikes including portions of Portville upstream.
12 Flood stage, flooding possible on Union Street in Allegany and East Riverside Drive 1 to 3 miles upstream of Olean. Some farm lands along the river are also impacted.
10 Action stage, high flows. No flooding.
About This Location Collapse

Latitude: 42.072222° N, Longitude: 78.451944° W, Horizontal Datum: NAD83/WGS84

River Stage
Reference Frame		 Gauge Height Flood Stage Uses
NWS stage 0 ft 12 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 1399.50 ft 1411.50 ft Survey grade GPS equipment, FEMA flood plain maps, newer USGS topographic maps
NGVD 29 1399.98 ft 1411.98 ft 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:
Additional Information Collapse
Potential River Levels - Used to
Potential River Levels
Used to Estimate the Chance of Flooding and the Range of Possible River Levels
10 Day (HEFS) 7 Day (NAEFS) 7 Day (GEFS)
HEFS Ensemble NAEFS Ensemble GEFS Ensemble

Note: Use the official hydrograph at the top of this web page for river levels within the next 48 hours.

See the Product Description Document link for more details on the interpretation of the 3,7 day graphics.

Click individual graphics to enlarge.

Observations courtesy of the town of Olean.
Resources Collapse
Hydrologic Resources Additional Resources
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
Buffalo Weather Forecast Office
587 Aero Drive
Buffalo, NY 14225-1405
(716) 565-0204
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