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Hydrograph River at a Glance Download
St. Marys River at Great Mills Stage (ft)Flow (cfs)Observed: 1.56 ft at 9:30AM Mar 15, 2023Observed: 1.56 ft at 9:45AM Mar 15, 2023Observed: 1.56 ft at 10:00AM Mar 15, 2023Observed: 1.56 ft at 10:15AM Mar 15, 2023Observed: 1.56 ft at 10:30AM Mar 15, 2023Observed: 1.55 ft at 10:45AM Mar 15, 2023Observed: 1.55 ft at 11:00AM Mar 15, 2023Observed: 1.56 ft at 11:15AM Mar 15, 2023Observed: 1.55 ft at 11:30AM Mar 15, 2023Observed: 1.55 ft at 11:45AM Mar 15, 2023Observed: 1.56 ft at 12:00PM Mar 15, 2023Observed: 1.55 ft at 12:15PM Mar 15, 2023Observed: 1.55 ft at 12:30PM Mar 15, 2023Observed: 1.56 ft at 12:45PM Mar 15, 2023Observed: 1.56 ft at 1:00PM Mar 15, 2023Observed: 1.56 ft at 1:15PM Mar 15, 2023Observed: 1.56 ft at 1:30PM Mar 15, 2023Observed: 1.56 ft at 1:45PM Mar 15, 2023Observed: 1.57 ft at 2:00PM Mar 15, 2023Observed: 1.57 ft at 2:15PM Mar 15, 2023Observed: 1.57 ft at 2:30PM Mar 15, 2023Observed: 1.57 ft at 2:45PM Mar 15, 2023Highest Observation: 1.58 ft at 3:00PM Mar 15, 2023Highest Observation: 1.58 ft at 3:15PM Mar 15, 2023Highest Observation: 1.58 ft at 3:30PM Mar 15, 2023Observed: 1.57 ft at 3:45PM Mar 15, 2023Highest Observation: 1.58 ft at 4:00PM Mar 15, 2023Observed: 1.57 ft at 4:15PM Mar 15, 2023Observed: 1.57 ft at 4:30PM Mar 15, 2023Observed: 1.57 ft at 4:45PM Mar 15, 2023Observed: 1.57 ft at 5:00PM Mar 15, 2023Observed: 1.57 ft at 5:15PM Mar 15, 2023Observed: 1.57 ft at 5:30PM Mar 15, 2023Observed: 1.57 ft at 5:45PM Mar 15, 2023Observed: 1.57 ft at 6:00PM Mar 15, 2023Observed: 1.57 ft at 6:15PM Mar 15, 2023Observed: 1.57 ft at 6:30PM Mar 15, 2023Observed: 1.57 ft at 6:45PM Mar 15, 2023Observed: 1.56 ft at 7:00PM Mar 15, 2023Observed: 1.56 ft at 7:15PM Mar 15, 2023Observed: 1.57 ft at 7:30PM Mar 15, 2023Observed: 1.57 ft at 7:45PM Mar 15, 2023Observed: 1.56 ft at 8:00PM Mar 15, 2023Observed: 1.56 ft at 8:15PM Mar 15, 2023Observed: 1.56 ft at 8:30PM Mar 15, 2023Observed: 1.56 ft at 8:45PM Mar 15, 2023Observed: 1.56 ft at 9:00PM Mar 15, 2023Observed: 1.56 ft at 9:15PM Mar 15, 2023Observed: 1.56 ft at 9:30PM Mar 15, 2023Observed: 1.57 ft at 9:45PM Mar 15, 2023Observed: 1.57 ft at 10:00PM Mar 15, 2023Observed: 1.56 ft at 10:15PM Mar 15, 2023Observed: 1.56 ft at 10:30PM Mar 15, 2023Observed: 1.56 ft at 10:45PM Mar 15, 2023Observed: 1.56 ft at 11:00PM Mar 15, 2023Observed: 1.56 ft at 11:15PM Mar 15, 2023Observed: 1.56 ft at 11:30PM Mar 15, 2023Observed: 1.56 ft at 11:45PM Mar 15, 2023Observed: 1.56 ft at 12:00AM Mar 16, 2023Observed: 1.56 ft at 12:15AM Mar 16, 2023Observed: 1.56 ft at 12:30AM Mar 16, 2023Observed: 1.56 ft at 12:45AM Mar 16, 2023Observed: 1.56 ft at 1:00AM Mar 16, 2023Observed: 1.56 ft at 1:15AM Mar 16, 2023Observed: 1.56 ft at 1:30AM Mar 16, 2023Observed: 1.56 ft at 1:45AM Mar 16, 2023Observed: 1.56 ft at 2:00AM Mar 16, 2023Observed: 1.56 ft at 2:15AM Mar 16, 2023Observed: 1.56 ft at 2:30AM Mar 16, 2023Observed: 1.56 ft at 2:45AM Mar 16, 2023Observed: 1.56 ft at 3:00AM Mar 16, 2023Observed: 1.56 ft at 3:15AM Mar 16, 2023Observed: 1.56 ft at 3:30AM Mar 16, 2023Observed: 1.56 ft at 3:45AM Mar 16, 2023Observed: 1.56 ft at 4:00AM Mar 16, 2023Observed: 1.55 ft at 4:15AM Mar 16, 2023Observed: 1.56 ft at 4:30AM Mar 16, 2023Observed: 1.55 ft at 4:45AM Mar 16, 2023Observed: 1.55 ft at 5:00AM Mar 16, 2023Observed: 1.55 ft at 5:15AM Mar 16, 2023Observed: 1.55 ft at 5:30AM Mar 16, 2023Observed: 1.55 ft at 5:45AM Mar 16, 2023Observed: 1.56 ft at 6:00AM Mar 16, 2023Observed: 1.55 ft at 6:15AM Mar 16, 2023Observed: 1.55 ft at 6:30AM Mar 16, 2023Observed: 1.56 ft at 6:45AM Mar 16, 2023Observed: 1.56 ft at 7:00AM Mar 16, 2023Observed: 1.56 ft at 7:15AM Mar 16, 2023Observed: 1.55 ft at 7:30AM Mar 16, 2023Observed: 1.55 ft at 7:45AM Mar 16, 2023Observed: 1.55 ft at 8:00AM Mar 16, 2023Observed: 1.55 ft at 8:15AM Mar 16, 2023Observed: 1.55 ft at 8:30AM Mar 16, 2023Observed: 1.54 ft at 8:45AM Mar 16, 2023Observed: 1.55 ft at 9:00AM Mar 16, 2023Observed: 1.55 ft at 9:15AM Mar 16, 2023Observed: 1.54 ft at 9:30AM Mar 16, 2023Observed: 1.54 ft at 9:45AM Mar 16, 2023Observed: 1.55 ft at 10:00AM Mar 16, 2023Observed: 1.54 ft at 10:15AM Mar 16, 2023Observed: 1.54 ft at 10:30AM Mar 16, 2023Observed: 1.54 ft at 10:45AM Mar 16, 2023Observed: 1.54 ft at 11:00AM Mar 16, 2023Observed: 1.55 ft at 11:15AM Mar 16, 2023Observed: 1.54 ft at 11:30AM Mar 16, 2023Observed: 1.53 ft at 11:45AM Mar 16, 2023Observed: 1.53 ft at 12:00PM Mar 16, 2023Observed: 1.54 ft at 12:15PM Mar 16, 2023Observed: 1.54 ft at 12:30PM Mar 16, 2023Observed: 1.54 ft at 12:45PM Mar 16, 2023Observed: 1.55 ft at 1:00PM Mar 16, 2023Observed: 1.55 ft at 1:15PM Mar 16, 2023Observed: 1.54 ft at 1:30PM Mar 16, 2023Observed: 1.54 ft at 1:45PM Mar 16, 2023Observed: 1.54 ft at 2:00PM Mar 16, 2023Observed: 1.54 ft at 2:15PM Mar 16, 2023Observed: 1.54 ft at 2:30PM Mar 16, 2023Observed: 1.55 ft at 2:45PM Mar 16, 2023Observed: 1.56 ft at 3:00PM Mar 16, 2023Observed: 1.55 ft at 3:15PM Mar 16, 2023Observed: 1.55 ft at 3:30PM Mar 16, 2023Observed: 1.55 ft at 3:45PM Mar 16, 2023Observed: 1.55 ft at 4:00PM Mar 16, 2023Observed: 1.55 ft at 4:15PM Mar 16, 2023Observed: 1.55 ft at 4:30PM Mar 16, 2023Observed: 1.55 ft at 4:45PM Mar 16, 2023Observed: 1.55 ft at 5:00PM Mar 16, 2023Observed: 1.55 ft at 5:15PM Mar 16, 2023Observed: 1.55 ft at 5:30PM Mar 16, 2023Observed: 1.55 ft at 5:45PM Mar 16, 2023Observed: 1.55 ft at 6:00PM Mar 16, 2023Observed: 1.55 ft at 6:15PM Mar 16, 2023Observed: 1.55 ft at 6:30PM Mar 16, 2023Observed: 1.56 ft at 6:45PM Mar 16, 2023Observed: 1.56 ft at 7:00PM Mar 16, 2023Observed: 1.56 ft at 7:15PM Mar 16, 2023Observed: 1.56 ft at 7:30PM Mar 16, 2023Observed: 1.56 ft at 7:45PM Mar 16, 2023Observed: 1.56 ft at 8:00PM Mar 16, 2023Observed: 1.55 ft at 8:15PM Mar 16, 2023Observed: 1.55 ft at 8:30PM Mar 16, 2023Observed: 1.55 ft at 8:45PM Mar 16, 2023Observed: 1.55 ft at 9:00PM Mar 16, 2023Observed: 1.55 ft at 9:15PM Mar 16, 2023Observed: 1.55 ft at 9:30PM Mar 16, 2023Observed: 1.55 ft at 9:45PM Mar 16, 2023Observed: 1.55 ft at 10:00PM Mar 16, 2023Observed: 1.55 ft at 10:15PM Mar 16, 2023Observed: 1.55 ft at 10:30PM Mar 16, 2023Observed: 1.55 ft at 10:45PM Mar 16, 2023Observed: 1.55 ft at 11:00PM Mar 16, 2023Observed: 1.55 ft at 11:15PM Mar 16, 2023Observed: 1.55 ft at 11:30PM Mar 16, 2023Observed: 1.55 ft at 11:45PM Mar 16, 2023Observed: 1.55 ft at 12:00AM Mar 17, 2023Observed: 1.55 ft at 12:15AM Mar 17, 2023Observed: 1.55 ft at 12:30AM Mar 17, 2023Observed: 1.54 ft at 12:45AM Mar 17, 2023Observed: 1.54 ft at 1:00AM Mar 17, 2023Observed: 1.54 ft at 1:15AM Mar 17, 2023Observed: 1.55 ft at 1:30AM Mar 17, 2023Observed: 1.55 ft at 1:45AM Mar 17, 2023Observed: 1.55 ft at 2:00AM Mar 17, 2023Observed: 1.55 ft at 2:15AM Mar 17, 2023Observed: 1.55 ft at 2:30AM Mar 17, 2023Observed: 1.55 ft at 2:45AM Mar 17, 2023Observed: 1.55 ft at 3:00AM Mar 17, 2023Observed: 1.55 ft at 3:15AM Mar 17, 2023Observed: 1.55 ft at 3:30AM Mar 17, 2023Observed: 1.55 ft at 3:45AM Mar 17, 2023Observed: 1.55 ft at 4:00AM Mar 17, 2023Observed: 1.55 ft at 4:15AM Mar 17, 2023Observed: 1.55 ft at 4:30AM Mar 17, 2023Observed: 1.55 ft at 4:45AM Mar 17, 2023Observed: 1.55 ft at 5:00AM Mar 17, 2023Observed: 1.55 ft at 5:15AM Mar 17, 2023Observed: 1.55 ft at 5:30AM Mar 17, 2023Observed: 1.55 ft at 5:45AM Mar 17, 2023Observed: 1.55 ft at 6:00AM Mar 17, 2023Observed: 1.55 ft at 6:15AM Mar 17, 2023Observed: 1.55 ft at 6:30AM Mar 17, 2023Observed: 1.55 ft at 6:45AM Mar 17, 2023Observed: 1.55 ft at 7:00AM Mar 17, 2023Observed: 1.55 ft at 7:15AM Mar 17, 2023Observed: 1.55 ft at 7:30AM Mar 17, 2023Observed: 1.55 ft at 7:45AM Mar 17, 2023Observed: 1.55 ft at 8:00AM Mar 17, 2023Observed: 1.55 ft at 8:15AM Mar 17, 2023Observed: 1.55 ft at 8:30AM Mar 17, 2023Observed: 1.55 ft at 8:45AM Mar 17, 2023Observed: 1.55 ft at 9:00AM Mar 17, 2023Observed: 1.55 ft at 9:15AM Mar 17, 2023Observed: 1.55 ft at 9:30AM Mar 17, 2023Observed: 1.55 ft at 9:45AM Mar 17, 2023Observed: 1.55 ft at 10:00AM Mar 17, 2023Observed: 1.55 ft at 10:15AM Mar 17, 2023Observed: 1.56 ft at 10:30AM Mar 17, 2023Observed: 1.56 ft at 10:45AM Mar 17, 2023Observed: 1.56 ft at 11:00AM Mar 17, 2023Observed: 1.56 ft at 11:15AM Mar 17, 2023Observed: 1.56 ft at 11:30AM Mar 17, 2023Observed: 1.56 ft at 11:45AM Mar 17, 2023Observed: 1.56 ft at 12:00PM Mar 17, 2023Observed: 1.56 ft at 12:15PM Mar 17, 2023Observed: 1.56 ft at 12:30PM Mar 17, 2023Observed: 1.56 ft at 12:45PM Mar 17, 2023Observed: 1.56 ft at 1:00PM Mar 17, 2023Observed: 1.55 ft at 1:15PM Mar 17, 2023Observed: 1.55 ft at 1:30PM Mar 17, 2023Observed: 1.55 ft at 1:45PM Mar 17, 2023Observed: 1.55 ft at 2:00PM Mar 17, 2023Observed: 1.55 ft at 2:15PM Mar 17, 2023Observed: 1.55 ft at 2:30PM Mar 17, 2023Observed: 1.55 ft at 2:45PM Mar 17, 2023Observed: 1.56 ft at 3:00PM Mar 17, 2023Observed: 1.56 ft at 3:15PM Mar 17, 2023Observed: 1.56 ft at 3:30PM Mar 17, 2023Observed: 1.55 ft at 3:45PM Mar 17, 2023Observed: 1.55 ft at 4:00PM Mar 17, 2023Observed: 1.55 ft at 4:15PM Mar 17, 2023Observed: 1.55 ft at 4:30PM Mar 17, 2023Observed: 1.55 ft at 4:45PM Mar 17, 2023Observed: 1.56 ft at 5:00PM Mar 17, 2023Observed: 1.56 ft at 5:15PM Mar 17, 2023Observed: 1.56 ft at 5:30PM Mar 17, 2023Observed: 1.56 ft at 5:45PM Mar 17, 2023Observed: 1.56 ft at 6:00PM Mar 17, 2023Observed: 1.56 ft at 6:15PM Mar 17, 2023Observed: 1.56 ft at 6:30PM Mar 17, 2023Observed: 1.55 ft at 6:45PM Mar 17, 2023Observed: 1.56 ft at 7:00PM Mar 17, 2023Observed: 1.55 ft at 7:15PM Mar 17, 2023Observed: 1.55 ft at 7:30PM Mar 17, 2023Observed: 1.55 ft at 7:45PM Mar 17, 2023Observed: 1.55 ft at 8:00PM Mar 17, 2023Observed: 1.55 ft at 8:15PM Mar 17, 2023Observed: 1.56 ft at 8:30PM Mar 17, 2023Observed: 1.56 ft at 8:45PM Mar 17, 2023Observed: 1.56 ft at 9:00PM Mar 17, 2023Observed: 1.56 ft at 9:15PM Mar 17, 2023Observed: 1.56 ft at 9:30PM Mar 17, 2023Observed: 1.55 ft at 9:45PM Mar 17, 2023Observed: 1.56 ft at 10:00PM Mar 17, 2023Observed: 1.55 ft at 10:15PM Mar 17, 2023Observed: 1.55 ft at 10:30PM Mar 17, 2023Observed: 1.55 ft at 10:45PM Mar 17, 2023Observed: 1.55 ft at 11:00PM Mar 17, 2023Observed: 1.55 ft at 11:15PM Mar 17, 2023Observed: 1.55 ft at 11:30PM Mar 17, 2023Observed: 1.55 ft at 11:45PM Mar 17, 2023Observed: 1.55 ft at 12:00AM Mar 18, 2023Observed: 1.55 ft at 12:15AM Mar 18, 2023Observed: 1.55 ft at 12:30AM Mar 18, 2023Observed: 1.55 ft at 12:45AM Mar 18, 2023Observed: 1.55 ft at 1:00AM Mar 18, 2023Observed: 1.55 ft at 1:15AM Mar 18, 2023Observed: 1.56 ft at 1:30AM Mar 18, 2023Observed: 1.56 ft at 1:45AM Mar 18, 2023Observed: 1.56 ft at 2:00AM Mar 18, 2023Observed: 1.56 ft at 2:15AM Mar 18, 2023Observed: 1.55 ft at 2:30AM Mar 18, 2023Observed: 1.55 ft at 2:45AM Mar 18, 2023Observed: 1.56 ft at 3:00AM Mar 18, 2023Observed: 1.56 ft at 3:15AM Mar 18, 2023Observed: 1.56 ft at 3:30AM Mar 18, 2023Observed: 1.56 ft at 3:45AM Mar 18, 2023Observed: 1.56 ft at 4:00AM Mar 18, 2023Observed: 1.56 ft at 4:15AM Mar 18, 2023Observed: 1.56 ft at 4:30AM Mar 18, 2023Observed: 1.56 ft at 4:45AM Mar 18, 2023Observed: 1.56 ft at 5:00AM Mar 18, 2023Observed: 1.56 ft at 5:15AM Mar 18, 2023Observed: 1.56 ft at 5:30AM Mar 18, 2023Observed: 1.57 ft at 5:45AM Mar 18, 2023Observed: 1.57 ft at 6:00AM Mar 18, 2023Observed: 1.57 ft at 6:15AM Mar 18, 2023Observed: 1.57 ft at 6:30AM Mar 18, 2023Observed: 1.57 ft at 6:45AM Mar 18, 2023Observed: 1.57 ft at 7:00AM Mar 18, 2023Observed: 1.57 ft at 7:15AM Mar 18, 2023Observed: 1.57 ft at 7:30AM Mar 18, 2023Observed: 1.57 ft at 7:45AM Mar 18, 2023Observed: 1.57 ft at 8:00AM Mar 18, 2023Observed: 1.57 ft at 8:15AM Mar 18, 2023Observed: 1.57 ft at 8:30AM Mar 18, 2023Observed: 1.57 ft at 8:45AM Mar 18, 2023Observed: 1.57 ft at 9:00AM Mar 18, 2023Observed: 1.57 ft at 9:15AM Mar 18, 2023Highest Observation: 1.58 ft at 9:30AM Mar 18, 2023Highest Observation: 1.58 ft at 9:45AM Mar 18, 2023Highest Observation: 1.58 ft at 10:00AM Mar 18, 2023Observed: 1.57 ft at 10:15AM Mar 18, 2023Highest Observation: 1.58 ft at 10:30AM Mar 18, 2023Observed: 1.57 ft at 10:45AM Mar 18, 2023Observed: 1.57 ft at 11:00AM Mar 18, 2023Observed: 1.57 ft at 11:15AM Mar 18, 2023Observed: 1.57 ft at 11:30AM Mar 18, 2023Observed: 1.57 ft at 11:45AM Mar 18, 2023Observed: 1.56 ft at 12:00PM Mar 18, 2023Observed: 1.57 ft at 12:15PM Mar 18, 2023Observed: 1.57 ft at 12:30PM Mar 18, 2023Highest Observation: 1.58 ft at 12:45PM Mar 18, 2023Highest Observation: 1.58 ft at 1:00PM Mar 18, 2023Highest Observation: 1.58 ft at 1:15PM Mar 18, 2023Highest Observation: 1.58 ft at 1:30PM Mar 18, 2023Highest Observation: 1.58 ft at 1:45PM Mar 18, 2023Highest Observation: 1.58 ft at 2:00PM Mar 18, 2023Observed: 1.57 ft at 2:15PM Mar 18, 2023Observed: 1.57 ft at 2:30PM Mar 18, 2023Highest Observation: 1.58 ft at 2:45PM Mar 18, 2023Highest Observation: 1.58 ft at 3:00PM Mar 18, 2023Observed: 1.57 ft at 3:15PM Mar 18, 2023Highest Observation: 1.58 ft at 3:30PM Mar 18, 2023Highest Observation: 1.58 ft at 3:45PM Mar 18, 2023Highest Observation: 1.58 ft at 4:00PM Mar 18, 2023Highest Observation: 1.58 ft at 4:15PM Mar 18, 2023Highest Observation: 1.58 ft at 4:30PM Mar 18, 2023Highest Observation: 1.58 ft at 4:45PM Mar 18, 2023Highest Observation: 1.58 ft at 5:00PM Mar 18, 2023Highest Observation: 1.58 ft at 5:15PM Mar 18, 2023Observed: 1.57 ft at 5:30PM Mar 18, 2023Observed: 1.57 ft at 5:45PM Mar 18, 2023Observed: 1.57 ft at 6:00PM Mar 18, 2023Observed: 1.57 ft at 6:15PM Mar 18, 2023Observed: 1.57 ft at 6:30PM Mar 18, 2023Observed: 1.57 ft at 6:45PM Mar 18, 2023Observed: 1.57 ft at 7:00PM Mar 18, 2023Observed: 1.57 ft at 7:15PM Mar 18, 2023Observed: 1.56 ft at 7:30PM Mar 18, 2023Observed: 1.56 ft at 7:45PM Mar 18, 2023Observed: 1.56 ft at 8:00PM Mar 18, 2023Observed: 1.56 ft at 8:15PM Mar 18, 2023Observed: 1.56 ft at 8:30PM Mar 18, 2023Observed: 1.56 ft at 8:45PM Mar 18, 2023Observed: 1.56 ft at 9:00PM Mar 18, 2023Observed: 1.56 ft at 9:15PM Mar 18, 2023Observed: 1.56 ft at 9:30PM Mar 18, 2023Observed: 1.56 ft at 9:45PM Mar 18, 2023Observed: 1.56 ft at 10:00PM Mar 18, 2023Observed: 1.56 ft at 10:15PM Mar 18, 2023Observed: 1.56 ft at 10:30PM Mar 18, 2023Observed: 1.56 ft at 10:45PM Mar 18, 2023Observed: 1.56 ft at 11:00PM Mar 18, 2023Observed: 1.56 ft at 11:15PM Mar 18, 2023Observed: 1.56 ft at 11:30PM Mar 18, 2023Observed: 1.56 ft at 11:45PM Mar 18, 2023Observed: 1.56 ft at 12:00AM Mar 19, 2023Observed: 1.56 ft at 12:15AM Mar 19, 2023Observed: 1.56 ft at 12:30AM Mar 19, 2023Observed: 1.56 ft at 12:45AM Mar 19, 2023Observed: 1.56 ft at 1:00AM Mar 19, 2023Observed: 1.56 ft at 1:15AM Mar 19, 2023Observed: 1.57 ft at 1:30AM Mar 19, 2023Observed: 1.57 ft at 1:45AM Mar 19, 2023Observed: 1.57 ft at 2:00AM Mar 19, 2023Observed: 1.57 ft at 2:15AM Mar 19, 2023Observed: 1.57 ft at 2:30AM Mar 19, 2023Observed: 1.57 ft at 2:45AM Mar 19, 2023Observed: 1.57 ft at 3:00AM Mar 19, 2023Observed: 1.57 ft at 3:15AM Mar 19, 2023Observed: 1.57 ft at 3:30AM Mar 19, 2023Observed: 1.57 ft at 3:45AM Mar 19, 2023Observed: 1.57 ft at 4:00AM Mar 19, 2023Observed: 1.56 ft at 4:15AM Mar 19, 2023Observed: 1.56 ft at 4:30AM Mar 19, 2023Observed: 1.57 ft at 4:45AM Mar 19, 2023Observed: 1.57 ft at 5:00AM Mar 19, 2023Observed: 1.56 ft at 5:15AM Mar 19, 2023Observed: 1.56 ft at 5:30AM Mar 19, 2023Observed: 1.56 ft at 5:45AM Mar 19, 2023Observed: 1.56 ft at 6:00AM Mar 19, 2023Observed: 1.56 ft at 6:15AM Mar 19, 2023Observed: 1.56 ft at 6:30AM Mar 19, 2023Observed: 1.56 ft at 6:45AM Mar 19, 2023Observed: 1.56 ft at 7:00AM Mar 19, 2023Observed: 1.56 ft at 7:15AM Mar 19, 2023Observed: 1.56 ft at 7:30AM Mar 19, 2023Observed: 1.56 ft at 7:45AM Mar 19, 2023Observed: 1.56 ft at 8:00AM Mar 19, 2023Observed: 1.55 ft at 8:15AM Mar 19, 2023Observed: 1.55 ft at 8:30AM Mar 19, 2023Observed: 1.55 ft at 8:45AM Mar 19, 2023Observed: 1.55 ft at 9:00AM Mar 19, 2023Observed: 1.55 ft at 9:15AM Mar 19, 2023Observed: 1.55 ft at 9:30AM Mar 19, 2023Observed: 1.55 ft at 9:45AM Mar 19, 2023Observed: 1.56 ft at 10:00AM Mar 19, 2023Observed: 1.55 ft at 10:15AM Mar 19, 2023Observed: 1.55 ft at 10:30AM Mar 19, 2023Observed: 1.55 ft at 10:45AM Mar 19, 2023Observed: 1.55 ft at 11:00AM Mar 19, 2023Observed: 1.56 ft at 11:15AM Mar 19, 2023Observed: 1.55 ft at 11:30AM Mar 19, 2023Observed: 1.54 ft at 11:45AM Mar 19, 2023Observed: 1.54 ft at 12:00PM Mar 19, 2023Observed: 1.55 ft at 12:15PM Mar 19, 2023Observed: 1.54 ft at 12:30PM Mar 19, 2023Observed: 1.55 ft at 12:45PM Mar 19, 2023Observed: 1.55 ft at 1:00PM Mar 19, 2023Observed: 1.56 ft at 1:15PM Mar 19, 2023Observed: 1.55 ft at 1:30PM Mar 19, 2023Observed: 1.55 ft at 1:45PM Mar 19, 2023Observed: 1.55 ft at 2:00PM Mar 19, 2023Observed: 1.55 ft at 2:15PM Mar 19, 2023Observed: 1.55 ft at 2:30PM Mar 19, 2023Observed: 1.55 ft at 2:45PM Mar 19, 2023Observed: 1.55 ft at 3:00PM Mar 19, 2023Observed: 1.55 ft at 3:15PM Mar 19, 2023Observed: 1.56 ft at 3:30PM Mar 19, 2023Observed: 1.56 ft at 3:45PM Mar 19, 2023Observed: 1.56 ft at 4:00PM Mar 19, 2023Observed: 1.55 ft at 4:15PM Mar 19, 2023Observed: 1.56 ft at 4:30PM Mar 19, 2023Observed: 1.56 ft at 4:45PM Mar 19, 2023Observed: 1.55 ft at 5:00PM Mar 19, 2023Observed: 1.55 ft at 5:15PM Mar 19, 2023Observed: 1.55 ft at 5:30PM Mar 19, 2023Observed: 1.55 ft at 5:45PM Mar 19, 2023Observed: 1.55 ft at 6:00PM Mar 19, 2023Observed: 1.55 ft at 6:15PM Mar 19, 2023Observed: 1.55 ft at 6:30PM Mar 19, 2023Observed: 1.55 ft at 6:45PM Mar 19, 2023Observed: 1.55 ft at 7:00PM Mar 19, 2023Observed: 1.55 ft at 7:15PM Mar 19, 2023Observed: 1.55 ft at 7:30PM Mar 19, 2023Observed: 1.55 ft at 7:45PM Mar 19, 2023Observed: 1.55 ft at 8:00PM Mar 19, 2023Observed: 1.55 ft at 8:15PM Mar 19, 2023Observed: 1.55 ft at 8:30PM Mar 19, 2023Observed: 1.55 ft at 8:45PM Mar 19, 2023Observed: 1.55 ft at 9:00PM Mar 19, 2023Observed: 1.55 ft at 9:15PM Mar 19, 2023Observed: 1.55 ft at 9:30PM Mar 19, 2023Observed: 1.55 ft at 9:45PM Mar 19, 2023Observed: 1.55 ft at 10:00PM Mar 19, 2023Observed: 1.55 ft at 10:15PM Mar 19, 2023Observed: 1.55 ft at 10:30PM Mar 19, 2023Observed: 1.55 ft at 10:45PM Mar 19, 2023Observed: 1.55 ft at 11:00PM Mar 19, 2023Observed: 1.55 ft at 11:15PM Mar 19, 2023Observed: 1.55 ft at 11:30PM Mar 19, 2023Observed: 1.55 ft at 11:45PM Mar 19, 2023Observed: 1.55 ft at 12:00AM Mar 20, 2023Observed: 1.55 ft at 12:15AM Mar 20, 2023Observed: 1.55 ft at 12:30AM Mar 20, 2023Observed: 1.54 ft at 12:45AM Mar 20, 2023Observed: 1.55 ft at 1:00AM Mar 20, 2023Observed: 1.55 ft at 1:15AM Mar 20, 2023Observed: 1.55 ft at 1:30AM Mar 20, 2023Observed: 1.55 ft at 1:45AM Mar 20, 2023Observed: 1.55 ft at 2:00AM Mar 20, 2023Observed: 1.55 ft at 2:15AM Mar 20, 2023Observed: 1.55 ft at 2:30AM Mar 20, 2023Observed: 1.55 ft at 2:45AM Mar 20, 2023Observed: 1.55 ft at 3:00AM Mar 20, 2023Observed: 1.55 ft at 3:15AM Mar 20, 2023Observed: 1.55 ft at 3:30AM Mar 20, 2023Observed: 1.54 ft at 3:45AM Mar 20, 2023Observed: 1.55 ft at 4:00AM Mar 20, 2023Observed: 1.54 ft at 4:15AM Mar 20, 2023Observed: 1.54 ft at 4:30AM Mar 20, 2023Observed: 1.54 ft at 4:45AM Mar 20, 2023Observed: 1.54 ft at 5:00AM Mar 20, 2023Observed: 1.54 ft at 5:15AM Mar 20, 2023Observed: 1.54 ft at 5:30AM Mar 20, 2023Observed: 1.54 ft at 5:45AM Mar 20, 2023Observed: 1.54 ft at 6:00AM Mar 20, 2023Observed: 1.54 ft at 6:15AM Mar 20, 2023Observed: 1.54 ft at 6:30AM Mar 20, 2023Observed: 1.54 ft at 6:45AM Mar 20, 2023Observed: 1.54 ft at 7:00AM Mar 20, 2023Observed: 1.54 ft at 7:15AM Mar 20, 2023Observed: 1.54 ft at 7:30AM Mar 20, 2023Observed: 1.54 ft at 7:45AM Mar 20, 2023Observed: 1.54 ft at 8:00AM Mar 20, 2023USGS--Water Resources of the United StatesGMRM2(plotting HGIRG) Graph Created (9:26AM Mar 20, 2023)ObservedLatest observed value: 1.54 ft at 8:00 AM EDT 20-Mar-2023. Flood Stage is 6 ft
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Tabular Data (UTC)
Tabular Data (EDT)
XML Data
RSS Files
Datum: Not Available
Metadata
NOTE: Forecasts are not available for the St. Marys River at Great Mills. Only observed stages are available for this point.
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Flood Categories (in feet)
Major Flood Stage: 10
Moderate Flood Stage: 8
Flood Stage: 6
Action Stage: 5
Low Stage (in feet): -9999

Historic Crests
(1) 13.34 ft on 08/20/1969
(2) 12.98 ft on 08/28/2011
(3) 12.82 ft on 09/16/1999
(4) 12.08 ft on 07/30/1960
(5) 11.77 ft on 08/13/1955
Show More Historic Crests

(P): Preliminary values subject to further review.

Recent Crests
(1) 6.04 ft on 12/16/2022 (P)
(2) 7.03 ft on 07/26/2022 (P)
(3) 6.06 ft on 05/24/2022 (P)
(4) 6.01 ft on 07/09/2021
(5) 6.75 ft on 06/10/2021
Show More Recent Crests

(P): Preliminary values subject to further review.

Low Water Records
Currently none available.

For more information on your flood risk go to www.floodsmart.gov.
Zoom Level:14
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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.
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10 Widespread flooding is occurring in Great Mills with water approaching homes and businesses.
8 Indian Bridge Road begins to flood as flooding becomes more widespread in Great Mills.
6 Flat Iron Road begins to flood with water in some yards in Great Mills.
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Latitude: 38.241667° N, Longitude: 76.503611° W, Horizontal Datum: NAD83/WGS84

River Stage
Reference Frame		 Gauge Height Flood Stage Uses
NWS stage 0 ft 6 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 Not Available Not Available 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:
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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
(Baltimore/Washington) Sterling Weather Forecast Office
43858 Weather Service Rd.
Sterling, VA 20166
(571) 888-3500
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