Allegheny River at Natrona Lock and Dam
Critical Stages
17.2' - Action
21' - Flood
24' - Moderate
26' - Major
Latest Observation
Updated: 10:15 AM EST 12/6/25
Status: No Flooding
Stage: 11.28 ft
Flow: 10.3 kcfs
Forecast
| Time | Stage (ft) | Flow (kcfs) |
|---|---|---|
| 1 PM 12/6 | 11.3 | 10.5 |
| 7 PM 12/6 | 11.2 | 9.74 |
| 1 AM 12/7 | 11.2 | 9.74 |
| 7 AM 12/7 | 11.2 | 9.74 |
| 1 PM 12/7 | 11.3 | 10.5 |
| 7 PM 12/7 | 11.3 | 10.5 |
| 1 AM 12/8 | 11.2 | 9.74 |
| 7 AM 12/8 | 11.2 | 9.74 |
| 1 PM 12/8 | 11.2 | 9.74 |
| 7 PM 12/8 | 11.2 | 9.74 |
| 1 AM 12/9 | 11.2 | 9.74 |
| 7 AM 12/9 | 11.2 | 9.74 |
| 1 PM 12/9 | 11.2 | 9.74 |
| 7 PM 12/9 | 11.1 | 8.98 |
| 1 AM 12/10 | 11.1 | 8.98 |
| 7 AM 12/10 | 11 | 8.26 |
| 1 PM 12/10 | 11 | 8.26 |
| 7 PM 12/10 | 11 | 8.26 |
| 1 AM 12/11 | 10.9 | 7.5 |
| 7 AM 12/11 | 10.9 | 7.5 |
| Time | Stage (ft) | Flow (kcfs) |
|---|---|---|
| 11:15 AM 12/6 | 11.3 | 10.5 |
| 11:00 AM 12/6 | 11.29 | 10.4 |
| 10:45 AM 12/6 | 11.29 | 10.4 |
| 10:30 AM 12/6 | 11.28 | 10.3 |
| 10:15 AM 12/6 | 11.28 | 10.3 |
| 10:00 AM 12/6 | 11.28 | 10.3 |
| 9:45 AM 12/6 | 11.27 | 10.2 |
| 9:30 AM 12/6 | 11.27 | 10.2 |
| 9:15 AM 12/6 | 11.27 | 10.2 |
| 9:00 AM 12/6 | 11.27 | 10.2 |
| 8:45 AM 12/6 | 11.28 | 10.3 |
| 8:30 AM 12/6 | 11.29 | 10.4 |
| 8:15 AM 12/6 | 11.29 | 10.4 |
| 8:00 AM 12/6 | 11.3 | 10.5 |
| 7:45 AM 12/6 | 11.3 | 10.5 |
| 7:30 AM 12/6 | 11.31 | 10.5 |
| 7:15 AM 12/6 | 11.31 | 10.5 |
| 7:00 AM 12/6 | 11.32 | 10.6 |
| 6:45 AM 12/6 | 11.32 | 10.6 |
| 6:30 AM 12/6 | 11.32 | 10.6 |
| 6:15 AM 12/6 | 11.33 | 10.7 |
| 6:00 AM 12/6 | 11.34 | 10.8 |
| 5:45 AM 12/6 | 11.34 | 10.8 |
| 5:30 AM 12/6 | 11.35 | 10.8 |
| 5:15 AM 12/6 | 11.36 | 10.9 |
| 5:00 AM 12/6 | 11.37 | 11 |
| 4:45 AM 12/6 | 11.38 | 11.1 |
| 4:30 AM 12/6 | 11.38 | 11.1 |
| 4:15 AM 12/6 | 11.39 | 11.2 |
| 4:00 AM 12/6 | 11.39 | 11.2 |
29.4' -
Pennsylvania Railroad main line and sidings affected at Tarentum PA, 3 miles downstream floods.
21.5' -
The Natrona Water Company is affected.
21.3' -
Water begins to back up into the sewers at Braeburn Steel Co.
21' -
Lock walls overtopped.
18' -
Navigation suspended, lock out of service.
| Date | Stage (ft) |
|---|---|
| Mar 18, 1936 | 32.1 |
| Dec 30, 1942 | 28.4 |
| Jan 22, 1959 | 27.6 |
| Jun 23, 1972 | 27.5 |
| Mar 10, 1964 | 26.4 |
| Sep 18, 2004 | 24.2 |
| Jan 20, 1996 | 23.1 |
| Feb 14, 1966 | 22.1 |
| Feb 17, 1976 | 21.8 |
| Mar 16, 2007 | 21.4 |
| Dec 31, 1990 | 20.7 |
| Jan 7, 2005 | 20 |
| Feb 9, 2019 | 18.63 |
| Feb 19, 2022 | 18.52 |
| Mar 24, 2007 | 17.84 |
Data provided by the National Weather Service.
