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Hydrograph River at a Glance Download
St. Marys River at Great Mills Stage (ft)Flow (cfs)Observed: 1.6 ft at 2:30PM Aug 02, 2022Observed: 1.59 ft at 2:45PM Aug 02, 2022Observed: 1.59 ft at 3:00PM Aug 02, 2022Observed: 1.6 ft at 3:15PM Aug 02, 2022Observed: 1.61 ft at 3:30PM Aug 02, 2022Observed: 1.6 ft at 3:45PM Aug 02, 2022Observed: 1.61 ft at 4:00PM Aug 02, 2022Observed: 1.6 ft at 4:15PM Aug 02, 2022Observed: 1.6 ft at 4:30PM Aug 02, 2022Observed: 1.6 ft at 4:45PM Aug 02, 2022Observed: 1.6 ft at 5:00PM Aug 02, 2022Observed: 1.6 ft at 5:15PM Aug 02, 2022Observed: 1.6 ft at 5:30PM Aug 02, 2022Observed: 1.6 ft at 5:45PM Aug 02, 2022Observed: 1.6 ft at 6:00PM Aug 02, 2022Observed: 1.6 ft at 6:15PM Aug 02, 2022Observed: 1.6 ft at 6:30PM Aug 02, 2022Observed: 1.6 ft at 6:45PM Aug 02, 2022Observed: 1.6 ft at 7:00PM Aug 02, 2022Observed: 1.59 ft at 7:15PM Aug 02, 2022Observed: 1.6 ft at 7:30PM Aug 02, 2022Observed: 1.6 ft at 7:45PM Aug 02, 2022Observed: 1.6 ft at 8:00PM Aug 02, 2022Observed: 1.59 ft at 8:15PM Aug 02, 2022Observed: 1.59 ft at 8:30PM Aug 02, 2022Observed: 1.59 ft at 8:45PM Aug 02, 2022Observed: 1.59 ft at 9:00PM Aug 02, 2022Observed: 1.59 ft at 9:15PM Aug 02, 2022Observed: 1.59 ft at 9:30PM Aug 02, 2022Observed: 1.59 ft at 9:45PM Aug 02, 2022Observed: 1.59 ft at 10:00PM Aug 02, 2022Observed: 1.59 ft at 10:15PM Aug 02, 2022Observed: 1.59 ft at 10:30PM Aug 02, 2022Observed: 1.59 ft at 10:45PM Aug 02, 2022Observed: 1.59 ft at 11:00PM Aug 02, 2022Observed: 1.59 ft at 11:15PM Aug 02, 2022Observed: 1.59 ft at 11:30PM Aug 02, 2022Observed: 1.59 ft at 11:45PM Aug 02, 2022Observed: 1.59 ft at 12:00AM Aug 03, 2022Observed: 1.59 ft at 12:15AM Aug 03, 2022Observed: 1.59 ft at 12:30AM Aug 03, 2022Observed: 1.59 ft at 12:45AM Aug 03, 2022Observed: 1.59 ft at 1:00AM Aug 03, 2022Observed: 1.59 ft at 1:15AM Aug 03, 2022Observed: 1.59 ft at 1:30AM Aug 03, 2022Observed: 1.59 ft at 1:45AM Aug 03, 2022Observed: 1.59 ft at 2:00AM Aug 03, 2022Observed: 1.59 ft at 2:15AM Aug 03, 2022Observed: 1.59 ft at 2:30AM Aug 03, 2022Observed: 1.59 ft at 2:45AM Aug 03, 2022Observed: 1.59 ft at 3:00AM Aug 03, 2022Observed: 1.59 ft at 3:15AM Aug 03, 2022Observed: 1.59 ft at 3:30AM Aug 03, 2022Observed: 1.59 ft at 3:45AM Aug 03, 2022Observed: 1.59 ft at 4:00AM Aug 03, 2022Observed: 1.58 ft at 4:15AM Aug 03, 2022Observed: 1.58 ft at 4:30AM Aug 03, 2022Observed: 1.58 ft at 4:45AM Aug 03, 2022Observed: 1.58 ft at 5:00AM Aug 03, 2022Observed: 1.58 ft at 5:15AM Aug 03, 2022Observed: 1.58 ft at 5:30AM Aug 03, 2022Observed: 1.58 ft at 5:45AM Aug 03, 2022Observed: 1.58 ft at 6:00AM Aug 03, 2022Observed: 1.58 ft at 6:15AM Aug 03, 2022Observed: 1.58 ft at 6:30AM Aug 03, 2022Observed: 1.58 ft at 6:45AM Aug 03, 2022Observed: 1.58 ft at 7:00AM Aug 03, 2022Observed: 1.58 ft at 7:15AM Aug 03, 2022Observed: 1.58 ft at 7:30AM Aug 03, 2022Observed: 1.58 ft at 7:45AM Aug 03, 2022Observed: 1.58 ft at 8:00AM Aug 03, 2022Observed: 1.58 ft at 8:15AM Aug 03, 2022Observed: 1.58 ft at 8:30AM Aug 03, 2022Observed: 1.57 ft at 8:45AM Aug 03, 2022Observed: 1.57 ft at 9:00AM Aug 03, 2022Observed: 1.57 ft at 9:15AM Aug 03, 2022Observed: 1.56 ft at 9:30AM Aug 03, 2022Observed: 1.56 ft at 9:45AM Aug 03, 2022Observed: 1.57 ft at 10:00AM Aug 03, 2022Observed: 1.56 ft at 10:15AM Aug 03, 2022Observed: 1.57 ft at 10:30AM Aug 03, 2022Observed: 1.56 ft at 10:45AM Aug 03, 2022Observed: 1.56 ft at 11:00AM Aug 03, 2022Observed: 1.56 ft at 11:15AM Aug 03, 2022Observed: 1.56 ft at 11:30AM Aug 03, 2022Observed: 1.56 ft at 11:45AM Aug 03, 2022Observed: 1.56 ft at 12:00PM Aug 03, 2022Observed: 1.56 ft at 12:15PM Aug 03, 2022Observed: 1.56 ft at 12:30PM Aug 03, 2022Observed: 1.56 ft at 12:45PM Aug 03, 2022Observed: 1.56 ft at 1:00PM Aug 03, 2022Observed: 1.56 ft at 1:15PM Aug 03, 2022Observed: 1.55 ft at 1:30PM Aug 03, 2022Observed: 1.55 ft at 1:45PM Aug 03, 2022Observed: 1.55 ft at 2:00PM Aug 03, 2022Observed: 1.55 ft at 2:15PM Aug 03, 2022Observed: 1.54 ft at 2:30PM Aug 03, 2022Observed: 1.55 ft at 2:45PM Aug 03, 2022Observed: 1.55 ft at 3:00PM Aug 03, 2022Observed: 1.55 ft at 3:15PM Aug 03, 2022Observed: 1.55 ft at 3:30PM Aug 03, 2022Observed: 1.55 ft at 3:45PM Aug 03, 2022Observed: 1.55 ft at 4:00PM Aug 03, 2022Observed: 1.55 ft at 4:15PM Aug 03, 2022Observed: 1.55 ft at 4:30PM Aug 03, 2022Observed: 1.55 ft at 4:45PM Aug 03, 2022Observed: 1.55 ft at 5:00PM Aug 03, 2022Observed: 1.54 ft at 5:15PM Aug 03, 2022Observed: 1.54 ft at 5:30PM Aug 03, 2022Observed: 1.55 ft at 5:45PM Aug 03, 2022Observed: 1.55 ft at 6:00PM Aug 03, 2022Observed: 1.55 ft at 6:15PM Aug 03, 2022Observed: 1.54 ft at 6:30PM Aug 03, 2022Observed: 1.54 ft at 6:45PM Aug 03, 2022Observed: 1.54 ft at 7:00PM Aug 03, 2022Observed: 1.54 ft at 7:15PM Aug 03, 2022Observed: 1.54 ft at 7:30PM Aug 03, 2022Observed: 1.54 ft at 7:45PM Aug 03, 2022Observed: 1.54 ft at 8:00PM Aug 03, 2022Observed: 1.54 ft at 8:15PM Aug 03, 2022Observed: 1.54 ft at 8:30PM Aug 03, 2022Observed: 1.54 ft at 8:45PM Aug 03, 2022Observed: 1.54 ft at 9:00PM Aug 03, 2022Observed: 1.54 ft at 9:15PM Aug 03, 2022Observed: 1.54 ft at 9:30PM Aug 03, 2022Observed: 1.54 ft at 9:45PM Aug 03, 2022Observed: 1.54 ft at 10:00PM Aug 03, 2022Observed: 1.54 ft at 10:15PM Aug 03, 2022Observed: 1.54 ft at 10:30PM Aug 03, 2022Observed: 1.54 ft at 10:45PM Aug 03, 2022Observed: 1.54 ft at 11:00PM Aug 03, 2022Observed: 1.54 ft at 11:15PM Aug 03, 2022Observed: 1.54 ft at 11:30PM Aug 03, 2022Observed: 1.54 ft at 11:45PM Aug 03, 2022Observed: 1.54 ft at 12:00AM Aug 04, 2022Observed: 1.54 ft at 12:15AM Aug 04, 2022Observed: 1.54 ft at 12:30AM Aug 04, 2022Observed: 1.54 ft at 12:45AM Aug 04, 2022Observed: 1.54 ft at 1:00AM Aug 04, 2022Observed: 1.54 ft at 1:15AM Aug 04, 2022Observed: 1.54 ft at 1:30AM Aug 04, 2022Observed: 1.54 ft at 1:45AM Aug 04, 2022Observed: 1.54 ft at 2:00AM Aug 04, 2022Observed: 1.54 ft at 2:15AM Aug 04, 2022Observed: 1.54 ft at 2:30AM Aug 04, 2022Observed: 1.54 ft at 2:45AM Aug 04, 2022Observed: 1.54 ft at 3:00AM Aug 04, 2022Observed: 1.54 ft at 3:15AM Aug 04, 2022Observed: 1.54 ft at 3:30AM Aug 04, 2022Observed: 1.54 ft at 3:45AM Aug 04, 2022Observed: 1.54 ft at 4:00AM Aug 04, 2022Observed: 1.54 ft at 4:15AM Aug 04, 2022Observed: 1.54 ft at 4:30AM Aug 04, 2022Observed: 1.54 ft at 4:45AM Aug 04, 2022Observed: 1.54 ft at 5:00AM Aug 04, 2022Observed: 1.54 ft at 5:15AM Aug 04, 2022Observed: 1.54 ft at 5:30AM Aug 04, 2022Observed: 1.54 ft at 5:45AM Aug 04, 2022Observed: 1.54 ft at 6:00AM Aug 04, 2022Observed: 1.54 ft at 6:15AM Aug 04, 2022Observed: 1.54 ft at 6:30AM Aug 04, 2022Observed: 1.54 ft at 6:45AM Aug 04, 2022Observed: 1.54 ft at 7:00AM Aug 04, 2022Observed: 1.54 ft at 7:15AM Aug 04, 2022Observed: 1.54 ft at 7:30AM Aug 04, 2022Observed: 1.54 ft at 7:45AM Aug 04, 2022Observed: 1.54 ft at 8:00AM Aug 04, 2022Observed: 1.53 ft at 9:15AM Aug 04, 2022Observed: 1.53 ft at 9:30AM Aug 04, 2022Observed: 1.53 ft at 9:45AM Aug 04, 2022Observed: 1.53 ft at 10:00AM Aug 04, 2022Observed: 1.53 ft at 10:15AM Aug 04, 2022Observed: 1.53 ft at 10:30AM Aug 04, 2022Observed: 1.53 ft at 10:45AM Aug 04, 2022Observed: 1.53 ft at 11:00AM Aug 04, 2022Observed: 1.53 ft at 11:15AM Aug 04, 2022Observed: 1.53 ft at 11:30AM Aug 04, 2022Observed: 1.53 ft at 11:45AM Aug 04, 2022Observed: 1.53 ft at 12:00PM Aug 04, 2022Observed: 1.53 ft at 12:15PM Aug 04, 2022Observed: 1.52 ft at 12:30PM Aug 04, 2022Observed: 1.53 ft at 12:45PM Aug 04, 2022Observed: 1.52 ft at 1:00PM Aug 04, 2022Observed: 1.52 ft at 1:15PM Aug 04, 2022Observed: 1.52 ft at 1:30PM Aug 04, 2022Observed: 1.5 ft at 1:45PM Aug 04, 2022Observed: 1.51 ft at 2:00PM Aug 04, 2022Observed: 1.51 ft at 2:15PM Aug 04, 2022Observed: 1.5 ft at 2:30PM Aug 04, 2022Observed: 1.51 ft at 2:45PM Aug 04, 2022Observed: 1.51 ft at 3:00PM Aug 04, 2022Observed: 1.52 ft at 3:15PM Aug 04, 2022Observed: 1.52 ft at 3:30PM Aug 04, 2022Observed: 1.52 ft at 3:45PM Aug 04, 2022Observed: 1.52 ft at 4:00PM Aug 04, 2022Observed: 1.52 ft at 4:15PM Aug 04, 2022Observed: 1.52 ft at 4:30PM Aug 04, 2022Observed: 1.51 ft at 4:45PM Aug 04, 2022Observed: 1.51 ft at 5:00PM Aug 04, 2022Observed: 1.51 ft at 5:15PM Aug 04, 2022Observed: 1.51 ft at 5:30PM Aug 04, 2022Observed: 1.51 ft at 5:45PM Aug 04, 2022Observed: 1.51 ft at 6:00PM Aug 04, 2022Observed: 1.51 ft at 6:15PM Aug 04, 2022Observed: 1.51 ft at 6:30PM Aug 04, 2022Observed: 1.51 ft at 6:45PM Aug 04, 2022Observed: 1.5 ft at 7:00PM Aug 04, 2022Observed: 1.51 ft at 7:15PM Aug 04, 2022Observed: 1.5 ft at 7:30PM Aug 04, 2022Observed: 1.5 ft at 7:45PM Aug 04, 2022Observed: 1.51 ft at 8:00PM Aug 04, 2022Observed: 1.5 ft at 8:15PM Aug 04, 2022Observed: 1.5 ft at 8:30PM Aug 04, 2022Observed: 1.5 ft at 8:45PM Aug 04, 2022Observed: 1.5 ft at 9:00PM Aug 04, 2022Observed: 1.5 ft at 9:15PM Aug 04, 2022Observed: 1.5 ft at 9:30PM Aug 04, 2022Observed: 1.5 ft at 9:45PM Aug 04, 2022Observed: 1.5 ft at 10:00PM Aug 04, 2022Observed: 1.5 ft at 10:15PM Aug 04, 2022Observed: 1.5 ft at 10:30PM Aug 04, 2022Observed: 1.5 ft at 10:45PM Aug 04, 2022Observed: 1.5 ft at 11:00PM Aug 04, 2022Observed: 1.5 ft at 11:15PM Aug 04, 2022Observed: 1.5 ft at 11:30PM Aug 04, 2022Observed: 1.5 ft at 11:45PM Aug 04, 2022Observed: 1.5 ft at 12:00AM Aug 05, 2022Observed: 1.5 ft at 12:15AM Aug 05, 2022Observed: 1.5 ft at 12:30AM Aug 05, 2022Observed: 1.5 ft at 12:45AM Aug 05, 2022Observed: 1.5 ft at 1:00AM Aug 05, 2022Observed: 1.5 ft at 1:15AM Aug 05, 2022Observed: 1.51 ft at 1:30AM Aug 05, 2022Observed: 1.51 ft at 1:45AM Aug 05, 2022Observed: 1.51 ft at 2:00AM Aug 05, 2022Observed: 1.51 ft at 2:15AM Aug 05, 2022Observed: 1.51 ft at 2:30AM Aug 05, 2022Observed: 1.52 ft at 2:45AM Aug 05, 2022Observed: 1.52 ft at 3:00AM Aug 05, 2022Observed: 1.52 ft at 3:15AM Aug 05, 2022Observed: 1.51 ft at 3:30AM Aug 05, 2022Observed: 1.52 ft at 3:45AM Aug 05, 2022Observed: 1.51 ft at 4:00AM Aug 05, 2022Observed: 1.52 ft at 4:15AM Aug 05, 2022Observed: 1.51 ft at 4:30AM Aug 05, 2022Observed: 1.51 ft at 4:45AM Aug 05, 2022Observed: 1.52 ft at 5:00AM Aug 05, 2022Observed: 1.52 ft at 5:15AM Aug 05, 2022Observed: 1.51 ft at 5:30AM Aug 05, 2022Observed: 1.51 ft at 5:45AM Aug 05, 2022Observed: 1.52 ft at 6:00AM Aug 05, 2022Observed: 1.51 ft at 6:15AM Aug 05, 2022Observed: 1.51 ft at 6:30AM Aug 05, 2022Observed: 1.52 ft at 6:45AM Aug 05, 2022Observed: 1.51 ft at 7:00AM Aug 05, 2022Observed: 1.51 ft at 7:15AM Aug 05, 2022Observed: 1.51 ft at 7:30AM Aug 05, 2022Observed: 1.51 ft at 7:45AM Aug 05, 2022Observed: 1.51 ft at 8:00AM Aug 05, 2022Observed: 1.51 ft at 8:15AM Aug 05, 2022Observed: 1.5 ft at 8:30AM Aug 05, 2022Observed: 1.5 ft at 8:45AM Aug 05, 2022Observed: 1.51 ft at 9:00AM Aug 05, 2022Observed: 1.51 ft at 9:15AM Aug 05, 2022Observed: 1.51 ft at 9:30AM Aug 05, 2022Observed: 1.5 ft at 9:45AM Aug 05, 2022Observed: 1.5 ft at 10:00AM Aug 05, 2022Observed: 1.5 ft at 10:15AM Aug 05, 2022Observed: 1.5 ft at 10:30AM Aug 05, 2022Observed: 1.5 ft at 10:45AM Aug 05, 2022Observed: 1.5 ft at 11:00AM Aug 05, 2022Observed: 1.5 ft at 11:15AM Aug 05, 2022Observed: 1.5 ft at 11:30AM Aug 05, 2022Observed: 1.5 ft at 11:45AM Aug 05, 2022Observed: 1.5 ft at 12:00PM Aug 05, 2022Observed: 1.5 ft at 12:15PM Aug 05, 2022Observed: 1.5 ft at 12:30PM Aug 05, 2022Observed: 1.5 ft at 12:45PM Aug 05, 2022Observed: 1.5 ft at 1:00PM Aug 05, 2022Observed: 1.49 ft at 1:15PM Aug 05, 2022Observed: 1.5 ft at 1:30PM Aug 05, 2022Observed: 1.49 ft at 1:45PM Aug 05, 2022Observed: 1.5 ft at 2:00PM Aug 05, 2022Observed: 1.5 ft at 2:15PM Aug 05, 2022Observed: 1.49 ft at 2:30PM Aug 05, 2022Observed: 1.49 ft at 2:45PM Aug 05, 2022Observed: 1.49 ft at 3:00PM Aug 05, 2022Observed: 1.5 ft at 3:15PM Aug 05, 2022Observed: 1.5 ft at 3:30PM Aug 05, 2022Observed: 1.5 ft at 3:45PM Aug 05, 2022Observed: 1.5 ft at 4:00PM Aug 05, 2022Observed: 1.5 ft at 4:15PM Aug 05, 2022Observed: 1.5 ft at 4:30PM Aug 05, 2022Observed: 1.5 ft at 4:45PM Aug 05, 2022Observed: 1.5 ft at 5:00PM Aug 05, 2022Observed: 1.49 ft at 5:15PM Aug 05, 2022Observed: 1.49 ft at 5:30PM Aug 05, 2022Observed: 1.5 ft at 5:45PM Aug 05, 2022Observed: 1.49 ft at 6:00PM Aug 05, 2022Observed: 1.49 ft at 6:15PM Aug 05, 2022Observed: 1.49 ft at 6:30PM Aug 05, 2022Observed: 1.5 ft at 6:45PM Aug 05, 2022Observed: 1.49 ft at 7:00PM Aug 05, 2022Observed: 1.5 ft at 7:15PM Aug 05, 2022Observed: 1.49 ft at 7:30PM Aug 05, 2022Observed: 1.54 ft at 7:45PM Aug 05, 2022Observed: 1.53 ft at 8:00PM Aug 05, 2022Observed: 1.54 ft at 8:15PM Aug 05, 2022Observed: 1.54 ft at 8:30PM Aug 05, 2022Observed: 1.55 ft at 8:45PM Aug 05, 2022Observed: 1.55 ft at 9:00PM Aug 05, 2022Observed: 1.56 ft at 9:15PM Aug 05, 2022Observed: 1.56 ft at 9:30PM Aug 05, 2022Observed: 1.57 ft at 9:45PM Aug 05, 2022Observed: 1.58 ft at 10:00PM Aug 05, 2022Observed: 1.59 ft at 10:15PM Aug 05, 2022Observed: 1.62 ft at 10:30PM Aug 05, 2022Observed: 1.66 ft at 10:45PM Aug 05, 2022Observed: 1.68 ft at 11:00PM Aug 05, 2022Observed: 1.69 ft at 11:15PM Aug 05, 2022Observed: 1.69 ft at 11:30PM Aug 05, 2022Observed: 1.71 ft at 11:45PM Aug 05, 2022Observed: 1.74 ft at 12:00AM Aug 06, 2022Observed: 1.8 ft at 12:15AM Aug 06, 2022Observed: 1.86 ft at 12:30AM Aug 06, 2022Observed: 1.91 ft at 12:45AM Aug 06, 2022Observed: 1.94 ft at 1:00AM Aug 06, 2022Highest Observation: 1.97 ft at 1:15AM Aug 06, 2022Highest Observation: 1.97 ft at 1:30AM Aug 06, 2022Observed: 1.96 ft at 1:45AM Aug 06, 2022Observed: 1.95 ft at 2:00AM Aug 06, 2022Observed: 1.93 ft at 2:15AM Aug 06, 2022Observed: 1.92 ft at 2:30AM Aug 06, 2022Observed: 1.9 ft at 2:45AM Aug 06, 2022Observed: 1.89 ft at 3:00AM Aug 06, 2022Observed: 1.87 ft at 3:15AM Aug 06, 2022Observed: 1.86 ft at 3:30AM Aug 06, 2022Observed: 1.85 ft at 3:45AM Aug 06, 2022Observed: 1.83 ft at 4:00AM Aug 06, 2022Observed: 1.82 ft at 4:15AM Aug 06, 2022Observed: 1.81 ft at 4:30AM Aug 06, 2022Observed: 1.8 ft at 4:45AM Aug 06, 2022Observed: 1.79 ft at 5:00AM Aug 06, 2022Observed: 1.78 ft at 5:15AM Aug 06, 2022Observed: 1.78 ft at 5:30AM Aug 06, 2022Observed: 1.77 ft at 5:45AM Aug 06, 2022Observed: 1.76 ft at 6:00AM Aug 06, 2022Observed: 1.76 ft at 6:15AM Aug 06, 2022Observed: 1.75 ft at 6:30AM Aug 06, 2022Observed: 1.75 ft at 6:45AM Aug 06, 2022Observed: 1.75 ft at 7:00AM Aug 06, 2022Observed: 1.75 ft at 7:15AM Aug 06, 2022Observed: 1.76 ft at 7:30AM Aug 06, 2022Observed: 1.76 ft at 7:45AM Aug 06, 2022Observed: 1.76 ft at 8:00AM Aug 06, 2022Observed: 1.77 ft at 8:15AM Aug 06, 2022Observed: 1.77 ft at 8:30AM Aug 06, 2022Observed: 1.78 ft at 8:45AM Aug 06, 2022Observed: 1.78 ft at 9:00AM Aug 06, 2022Observed: 1.78 ft at 9:15AM Aug 06, 2022Observed: 1.79 ft at 9:30AM Aug 06, 2022Observed: 1.79 ft at 9:45AM Aug 06, 2022Observed: 1.8 ft at 10:00AM Aug 06, 2022Observed: 1.8 ft at 10:15AM Aug 06, 2022Observed: 1.8 ft at 10:30AM Aug 06, 2022Observed: 1.8 ft at 10:45AM Aug 06, 2022Observed: 1.81 ft at 11:00AM Aug 06, 2022Observed: 1.81 ft at 11:15AM Aug 06, 2022Observed: 1.81 ft at 11:30AM Aug 06, 2022Observed: 1.82 ft at 11:45AM Aug 06, 2022Observed: 1.81 ft at 12:00PM Aug 06, 2022Observed: 1.82 ft at 12:15PM Aug 06, 2022Observed: 1.82 ft at 12:30PM Aug 06, 2022Observed: 1.82 ft at 12:45PM Aug 06, 2022Observed: 1.82 ft at 1:00PM Aug 06, 2022Observed: 1.82 ft at 1:15PM Aug 06, 2022Observed: 1.82 ft at 1:30PM Aug 06, 2022Observed: 1.83 ft at 1:45PM Aug 06, 2022Observed: 1.82 ft at 2:00PM Aug 06, 2022Observed: 1.83 ft at 2:15PM Aug 06, 2022Observed: 1.82 ft at 2:30PM Aug 06, 2022Observed: 1.82 ft at 2:45PM Aug 06, 2022Observed: 1.82 ft at 3:00PM Aug 06, 2022Observed: 1.82 ft at 3:15PM Aug 06, 2022Observed: 1.82 ft at 3:30PM Aug 06, 2022Observed: 1.82 ft at 3:45PM Aug 06, 2022Observed: 1.82 ft at 4:00PM Aug 06, 2022Observed: 1.82 ft at 4:15PM Aug 06, 2022Observed: 1.82 ft at 4:30PM Aug 06, 2022Observed: 1.83 ft at 4:45PM Aug 06, 2022Observed: 1.82 ft at 5:00PM Aug 06, 2022Observed: 1.82 ft at 5:15PM Aug 06, 2022Observed: 1.83 ft at 5:30PM Aug 06, 2022Observed: 1.82 ft at 5:45PM Aug 06, 2022Observed: 1.83 ft at 6:00PM Aug 06, 2022Observed: 1.83 ft at 6:15PM Aug 06, 2022Observed: 1.83 ft at 6:30PM Aug 06, 2022Observed: 1.83 ft at 6:45PM Aug 06, 2022Observed: 1.83 ft at 7:00PM Aug 06, 2022Observed: 1.82 ft at 7:15PM Aug 06, 2022Observed: 1.82 ft at 7:30PM Aug 06, 2022Observed: 1.82 ft at 7:45PM Aug 06, 2022Observed: 1.82 ft at 8:00PM Aug 06, 2022Observed: 1.81 ft at 8:15PM Aug 06, 2022Observed: 1.81 ft at 8:30PM Aug 06, 2022Observed: 1.81 ft at 8:45PM Aug 06, 2022Observed: 1.81 ft at 9:00PM Aug 06, 2022Observed: 1.81 ft at 9:15PM Aug 06, 2022Observed: 1.81 ft at 9:30PM Aug 06, 2022Observed: 1.8 ft at 9:45PM Aug 06, 2022Observed: 1.81 ft at 10:00PM Aug 06, 2022Observed: 1.8 ft at 10:15PM Aug 06, 2022Observed: 1.81 ft at 10:30PM Aug 06, 2022Observed: 1.8 ft at 10:45PM Aug 06, 2022Observed: 1.8 ft at 11:00PM Aug 06, 2022Observed: 1.8 ft at 11:15PM Aug 06, 2022Observed: 1.79 ft at 11:30PM Aug 06, 2022Observed: 1.79 ft at 11:45PM Aug 06, 2022Observed: 1.79 ft at 12:00AM Aug 07, 2022Observed: 1.79 ft at 12:15AM Aug 07, 2022Observed: 1.78 ft at 12:30AM Aug 07, 2022Observed: 1.78 ft at 12:45AM Aug 07, 2022Observed: 1.78 ft at 1:00AM Aug 07, 2022Observed: 1.78 ft at 1:15AM Aug 07, 2022Observed: 1.77 ft at 1:30AM Aug 07, 2022Observed: 1.77 ft at 1:45AM Aug 07, 2022Observed: 1.77 ft at 2:00AM Aug 07, 2022Observed: 1.77 ft at 2:15AM Aug 07, 2022Observed: 1.77 ft at 2:30AM Aug 07, 2022Observed: 1.77 ft at 2:45AM Aug 07, 2022Observed: 1.77 ft at 3:00AM Aug 07, 2022Observed: 1.76 ft at 3:15AM Aug 07, 2022Observed: 1.76 ft at 3:30AM Aug 07, 2022Observed: 1.75 ft at 3:45AM Aug 07, 2022Observed: 1.75 ft at 4:00AM Aug 07, 2022Observed: 1.75 ft at 4:15AM Aug 07, 2022Observed: 1.74 ft at 4:30AM Aug 07, 2022Observed: 1.74 ft at 4:45AM Aug 07, 2022Observed: 1.73 ft at 5:00AM Aug 07, 2022Observed: 1.73 ft at 5:15AM Aug 07, 2022Observed: 1.73 ft at 5:30AM Aug 07, 2022Observed: 1.72 ft at 5:45AM Aug 07, 2022Observed: 1.72 ft at 6:00AM Aug 07, 2022Observed: 1.72 ft at 6:15AM Aug 07, 2022Observed: 1.72 ft at 6:30AM Aug 07, 2022Observed: 1.72 ft at 6:45AM Aug 07, 2022Observed: 1.71 ft at 7:00AM Aug 07, 2022Observed: 1.71 ft at 7:15AM Aug 07, 2022Observed: 1.71 ft at 7:30AM Aug 07, 2022Observed: 1.71 ft at 7:45AM Aug 07, 2022Observed: 1.7 ft at 8:00AM Aug 07, 2022Observed: 1.7 ft at 8:15AM Aug 07, 2022Observed: 1.7 ft at 8:30AM Aug 07, 2022Observed: 1.7 ft at 8:45AM Aug 07, 2022Observed: 1.69 ft at 9:00AM Aug 07, 2022Observed: 1.68 ft at 9:15AM Aug 07, 2022Observed: 1.68 ft at 9:30AM Aug 07, 2022Observed: 1.67 ft at 9:45AM Aug 07, 2022Observed: 1.67 ft at 10:00AM Aug 07, 2022Observed: 1.67 ft at 10:15AM Aug 07, 2022Observed: 1.67 ft at 10:30AM Aug 07, 2022Observed: 1.67 ft at 10:45AM Aug 07, 2022Observed: 1.66 ft at 11:00AM Aug 07, 2022Observed: 1.66 ft at 11:15AM Aug 07, 2022Observed: 1.66 ft at 11:30AM Aug 07, 2022Observed: 1.66 ft at 11:45AM Aug 07, 2022Observed: 1.66 ft at 12:00PM Aug 07, 2022Observed: 1.66 ft at 12:15PM Aug 07, 2022Observed: 1.65 ft at 12:30PM Aug 07, 2022Observed: 1.65 ft at 12:45PM Aug 07, 2022Observed: 1.65 ft at 1:00PM Aug 07, 2022USGS--Water Resources of the United StatesGMRM2(plotting HGIRG) Graph Created (2:28PM Aug 7, 2022)ObservedLatest observed value: 1.65 ft at 1:00 PM EDT 7-Aug-2022. Flood Stage is 6 ft
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Tabular Data (UTC)
Tabular Data (EDT)
XML Data
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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
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(P): Preliminary values subject to further review.

Recent Crests
(1) 6.01 ft on 07/09/2021
(2) 6.75 ft on 06/10/2021
(3) 6.76 ft on 03/24/2021
(4) 11.57 ft on 08/04/2020
(5) 7.45 ft on 07/08/2019 (P)
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
(703) 996-2200
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