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St. Marys River at Decatur

Critical Stages
13' - Action
17' - Flood
20' - Moderate
24' - Major

Latest Observation

Updated: 11:40 PM EST 12/4/25

Status: No Flooding

Stage: 2.79 ft

Flow: 0.0244 kcfs

Forecast

Forecast not available for this location.

TimeStage (ft)Flow (kcfs)
11:40 PM 12/4 2.79 0.0244
11:35 PM 12/4 2.8 0.0252
11:30 PM 12/4 2.8 0.0252
11:25 PM 12/4 2.79 0.0244
11:20 PM 12/4 2.8 0.0252
11:15 PM 12/4 2.8 0.0252
11:10 PM 12/4 2.8 0.0252
11:05 PM 12/4 2.8 0.0252
11:00 PM 12/4 2.81 0.0259
10:55 PM 12/4 2.81 0.0259
10:50 PM 12/4 2.82 0.0267
10:45 PM 12/4 2.82 0.0267
10:40 PM 12/4 2.82 0.0267
10:35 PM 12/4 2.82 0.0267
10:30 PM 12/4 2.82 0.0267
10:25 PM 12/4 2.83 0.0275
10:20 PM 12/4 2.83 0.0275
10:15 PM 12/4 2.83 0.0275
10:10 PM 12/4 2.83 0.0275
10:05 PM 12/4 2.83 0.0275
10:00 PM 12/4 2.83 0.0275
9:55 PM 12/4 2.83 0.0275
9:50 PM 12/4 2.83 0.0275
9:45 PM 12/4 2.83 0.0275
9:40 PM 12/4 2.83 0.0275
9:35 PM 12/4 2.83 0.0275
9:30 PM 12/4 2.83 0.0275
9:25 PM 12/4 2.83 0.0275
9:20 PM 12/4 2.83 0.0275
9:15 PM 12/4 2.83 0.0275
Hydrograph for St. Marys River at Decatur
30.6' - Flood water begins to hit the bottom of the bridge at the gage site.
27.5' - Flood water reaches the 100 year flood level.
26.5' - Record flooding is in progress. Evacuations are necessary in Decatur, Indiana and Wilshire, Ohio. Serious flooding of the Central Soya Plant can be expected along with widespread flooding and disruption of land transportation.
24.5' - Major flooding is in progress with water at the top of the levee protecting the Central Soya Plant. US Highway 33 near Willshire, Ohio begins to flood. Extensive flooding of the east side of Decatur along with Bellmont High School occurs. Evacuations become necessary.
23.5' - Many east side city streets and county roads are flooded. Evacuation of east side residents near Bellmont High School becomes necessary.
23' - Portions of Ohio Routes 33, 49 and 81 are closed near Willshire.
22.5' - Piqua Road begins to flood at Decatur. Evacuations begin on Ogg Street. Ohio State Route 49 near Willshire becomes flooded.
21.5' - High water affects Piqua Rd...Ohio State Route 49 near the state line along with east side Decatur streets. Residential flooding begins on East Jackson and Ogg Streets. Bellmont High School grounds begin flooding.
20.5' - Indiana 101 north of Pleasant Mills is closed by flood water. Extensive agricultural flooding is in progress. Residents of the east and southeast side of Decatur become concerned.
19.5' - Flooding expands into more farm land in the Decatur area. Flood waters approach Piqua Road...Ohio State Route 49 and Indiana 101 just north of Pleasant Mills. Flood water begins to cross Ohio highway 49 north of Willshire, Ohio.
18.8' - Flood water begins to cross Ohio Highway 49 north of Willshire, Ohio.
18.5' - County Road 225 North...just north of Pleasant Mills Indiana is closed by flood water. Low land areas of Kekionga Park on the southeast side of Decatur begin flooding. Flooding is limited to farm land in Pleasant Mills Indiana and Willshire Ohio.
17.5' - County road 225 north of Pleasant Mills is flooded. Agricultural land flooding increases in northern...central and eastern Adams County.
17' - Agricultural flooding occurs along the river in northern...central and eastern Adams County.
DateStage (ft)
Jul 9, 2003 26.92
Jun 18, 2015 25.11
Mar 14, 1982 24.4
Feb 25, 1985 24.31
Feb 10, 1959 24.22
Jan 14, 2005 24.2
Jul 17, 1992 24.13
Dec 31, 1990 23.81
Feb 8, 2008 23.6
Feb 15, 1950 23.6
Mar 23, 1978 23.55
May 18, 1943 23.4
Jan 25, 1999 23.13
Jan 22, 1974 22.86
Jun 4, 1980 22.69
Mar 5, 1979 22.59
Mar 3, 2011 22.49
Apr 23, 1972 22.42
Dec 19, 1977 22.32
Feb 18, 1976 22.26

Data provided by the National Weather Service.