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Hydrograph River at a Glance Download
St. Marys River at Great Mills Stage (ft)Flow (cfs)Observed: 1.5 ft at 3:45PM Sep 22, 2021Observed: 1.49 ft at 4:00PM Sep 22, 2021Observed: 1.49 ft at 4:15PM Sep 22, 2021Observed: 1.48 ft at 4:30PM Sep 22, 2021Observed: 1.49 ft at 4:45PM Sep 22, 2021Observed: 1.49 ft at 5:00PM Sep 22, 2021Observed: 1.49 ft at 5:15PM Sep 22, 2021Observed: 1.48 ft at 5:30PM Sep 22, 2021Observed: 1.48 ft at 5:45PM Sep 22, 2021Observed: 1.48 ft at 6:00PM Sep 22, 2021Observed: 1.48 ft at 6:15PM Sep 22, 2021Observed: 1.48 ft at 6:30PM Sep 22, 2021Observed: 1.48 ft at 6:45PM Sep 22, 2021Observed: 1.48 ft at 7:00PM Sep 22, 2021Observed: 1.48 ft at 7:15PM Sep 22, 2021Observed: 1.48 ft at 7:30PM Sep 22, 2021Observed: 1.49 ft at 7:45PM Sep 22, 2021Observed: 1.49 ft at 8:00PM Sep 22, 2021Observed: 1.49 ft at 8:15PM Sep 22, 2021Observed: 1.5 ft at 8:30PM Sep 22, 2021Observed: 1.5 ft at 8:45PM Sep 22, 2021Observed: 1.51 ft at 9:00PM Sep 22, 2021Observed: 1.51 ft at 9:15PM Sep 22, 2021Observed: 1.51 ft at 9:30PM Sep 22, 2021Observed: 1.51 ft at 9:45PM Sep 22, 2021Observed: 1.52 ft at 10:00PM Sep 22, 2021Observed: 1.52 ft at 10:15PM Sep 22, 2021Observed: 1.52 ft at 10:30PM Sep 22, 2021Observed: 1.54 ft at 10:45PM Sep 22, 2021Observed: 1.56 ft at 11:00PM Sep 22, 2021Observed: 1.58 ft at 11:15PM Sep 22, 2021Observed: 1.59 ft at 11:30PM Sep 22, 2021Observed: 1.6 ft at 11:45PM Sep 22, 2021Observed: 1.61 ft at 12:00AM Sep 23, 2021Observed: 1.62 ft at 12:15AM Sep 23, 2021Observed: 1.63 ft at 12:30AM Sep 23, 2021Observed: 1.65 ft at 12:45AM Sep 23, 2021Observed: 1.66 ft at 1:00AM Sep 23, 2021Observed: 1.66 ft at 1:15AM Sep 23, 2021Observed: 1.66 ft at 1:30AM Sep 23, 2021Observed: 1.66 ft at 1:45AM Sep 23, 2021Observed: 1.66 ft at 2:00AM Sep 23, 2021Observed: 1.65 ft at 2:15AM Sep 23, 2021Observed: 1.65 ft at 2:30AM Sep 23, 2021Observed: 1.64 ft at 2:45AM Sep 23, 2021Observed: 1.64 ft at 3:00AM Sep 23, 2021Observed: 1.63 ft at 3:15AM Sep 23, 2021Observed: 1.63 ft at 3:30AM Sep 23, 2021Observed: 1.62 ft at 3:45AM Sep 23, 2021Observed: 1.61 ft at 4:00AM Sep 23, 2021Observed: 1.61 ft at 4:15AM Sep 23, 2021Observed: 1.61 ft at 4:30AM Sep 23, 2021Observed: 1.61 ft at 4:45AM Sep 23, 2021Observed: 1.6 ft at 5:00AM Sep 23, 2021Observed: 1.6 ft at 5:15AM Sep 23, 2021Observed: 1.6 ft at 5:30AM Sep 23, 2021Observed: 1.59 ft at 5:45AM Sep 23, 2021Observed: 1.59 ft at 6:00AM Sep 23, 2021Observed: 1.58 ft at 6:15AM Sep 23, 2021Observed: 1.58 ft at 6:30AM Sep 23, 2021Observed: 1.58 ft at 6:45AM Sep 23, 2021Observed: 1.58 ft at 7:00AM Sep 23, 2021Observed: 1.58 ft at 7:15AM Sep 23, 2021Observed: 1.58 ft at 7:30AM Sep 23, 2021Observed: 1.57 ft at 7:45AM Sep 23, 2021Observed: 1.57 ft at 8:00AM Sep 23, 2021Observed: 1.57 ft at 8:15AM Sep 23, 2021Observed: 1.57 ft at 8:30AM Sep 23, 2021Observed: 1.56 ft at 8:45AM Sep 23, 2021Observed: 1.56 ft at 9:00AM Sep 23, 2021Observed: 1.57 ft at 9:15AM Sep 23, 2021Observed: 1.57 ft at 9:30AM Sep 23, 2021Observed: 1.57 ft at 9:45AM Sep 23, 2021Observed: 1.58 ft at 10:00AM Sep 23, 2021Observed: 1.58 ft at 10:15AM Sep 23, 2021Observed: 1.58 ft at 10:30AM Sep 23, 2021Observed: 1.58 ft at 10:45AM Sep 23, 2021Observed: 1.58 ft at 11:00AM Sep 23, 2021Observed: 1.59 ft at 11:15AM Sep 23, 2021Observed: 1.61 ft at 11:30AM Sep 23, 2021Observed: 1.62 ft at 11:45AM Sep 23, 2021Observed: 1.62 ft at 12:00PM Sep 23, 2021Observed: 1.62 ft at 12:15PM Sep 23, 2021Observed: 1.62 ft at 12:30PM Sep 23, 2021Observed: 1.62 ft at 12:45PM Sep 23, 2021Observed: 1.63 ft at 1:00PM Sep 23, 2021Observed: 1.64 ft at 1:15PM Sep 23, 2021Observed: 1.66 ft at 1:30PM Sep 23, 2021Observed: 1.67 ft at 1:45PM Sep 23, 2021Observed: 1.68 ft at 2:00PM Sep 23, 2021Observed: 1.7 ft at 2:15PM Sep 23, 2021Observed: 1.72 ft at 2:30PM Sep 23, 2021Observed: 1.73 ft at 2:45PM Sep 23, 2021Observed: 1.73 ft at 3:00PM Sep 23, 2021Observed: 1.76 ft at 3:15PM Sep 23, 2021Observed: 1.83 ft at 3:30PM Sep 23, 2021Observed: 1.9 ft at 3:45PM Sep 23, 2021Observed: 1.95 ft at 4:00PM Sep 23, 2021Highest Observation: 1.97 ft at 4:15PM Sep 23, 2021Highest Observation: 1.97 ft at 4:30PM Sep 23, 2021Observed: 1.96 ft at 4:45PM Sep 23, 2021Observed: 1.94 ft at 5:00PM Sep 23, 2021Observed: 1.91 ft at 5:15PM Sep 23, 2021Observed: 1.89 ft at 5:30PM Sep 23, 2021Observed: 1.86 ft at 5:45PM Sep 23, 2021Observed: 1.84 ft at 6:00PM Sep 23, 2021Observed: 1.83 ft at 6:15PM Sep 23, 2021Observed: 1.81 ft at 6:30PM Sep 23, 2021Observed: 1.81 ft at 6:45PM Sep 23, 2021Observed: 1.79 ft at 7:00PM Sep 23, 2021Observed: 1.78 ft at 7:15PM Sep 23, 2021Observed: 1.77 ft at 7:30PM Sep 23, 2021Observed: 1.76 ft at 7:45PM Sep 23, 2021Observed: 1.75 ft at 8:00PM Sep 23, 2021Observed: 1.74 ft at 8:15PM Sep 23, 2021Observed: 1.74 ft at 8:30PM Sep 23, 2021Observed: 1.73 ft at 8:45PM Sep 23, 2021Observed: 1.72 ft at 9:00PM Sep 23, 2021Observed: 1.72 ft at 9:15PM Sep 23, 2021Observed: 1.71 ft at 9:30PM Sep 23, 2021Observed: 1.71 ft at 9:45PM Sep 23, 2021Observed: 1.7 ft at 10:00PM Sep 23, 2021Observed: 1.69 ft at 10:15PM Sep 23, 2021Observed: 1.69 ft at 10:30PM Sep 23, 2021Observed: 1.68 ft at 10:45PM Sep 23, 2021Observed: 1.68 ft at 11:00PM Sep 23, 2021Observed: 1.67 ft at 11:15PM Sep 23, 2021Observed: 1.67 ft at 11:30PM Sep 23, 2021Observed: 1.66 ft at 11:45PM Sep 23, 2021Observed: 1.66 ft at 12:00AM Sep 24, 2021Observed: 1.65 ft at 12:15AM Sep 24, 2021Observed: 1.65 ft at 12:30AM Sep 24, 2021Observed: 1.65 ft at 12:45AM Sep 24, 2021Observed: 1.64 ft at 1:00AM Sep 24, 2021Observed: 1.64 ft at 1:15AM Sep 24, 2021Observed: 1.64 ft at 1:30AM Sep 24, 2021Observed: 1.63 ft at 1:45AM Sep 24, 2021Observed: 1.63 ft at 2:00AM Sep 24, 2021Observed: 1.63 ft at 2:15AM Sep 24, 2021Observed: 1.63 ft at 2:30AM Sep 24, 2021Observed: 1.63 ft at 2:45AM Sep 24, 2021Observed: 1.62 ft at 3:00AM Sep 24, 2021Observed: 1.62 ft at 3:15AM Sep 24, 2021Observed: 1.62 ft at 3:30AM Sep 24, 2021Observed: 1.62 ft at 3:45AM Sep 24, 2021Observed: 1.62 ft at 4:00AM Sep 24, 2021Observed: 1.62 ft at 4:15AM Sep 24, 2021Observed: 1.61 ft at 4:30AM Sep 24, 2021Observed: 1.61 ft at 4:45AM Sep 24, 2021Observed: 1.61 ft at 5:00AM Sep 24, 2021Observed: 1.61 ft at 5:15AM Sep 24, 2021Observed: 1.61 ft at 5:30AM Sep 24, 2021Observed: 1.61 ft at 5:45AM Sep 24, 2021Observed: 1.61 ft at 6:00AM Sep 24, 2021Observed: 1.6 ft at 6:15AM Sep 24, 2021Observed: 1.6 ft at 6:30AM Sep 24, 2021Observed: 1.6 ft at 6:45AM Sep 24, 2021Observed: 1.6 ft at 7:00AM Sep 24, 2021Observed: 1.6 ft at 7:15AM Sep 24, 2021Observed: 1.6 ft at 7:30AM Sep 24, 2021Observed: 1.59 ft at 7:45AM Sep 24, 2021Observed: 1.59 ft at 8:00AM Sep 24, 2021Observed: 1.59 ft at 8:15AM Sep 24, 2021Observed: 1.59 ft at 8:30AM Sep 24, 2021Observed: 1.58 ft at 8:45AM Sep 24, 2021Observed: 1.58 ft at 9:00AM Sep 24, 2021Observed: 1.59 ft at 9:15AM Sep 24, 2021Observed: 1.59 ft at 9:30AM Sep 24, 2021Observed: 1.59 ft at 9:45AM Sep 24, 2021Observed: 1.59 ft at 10:00AM Sep 24, 2021Observed: 1.59 ft at 10:15AM Sep 24, 2021Observed: 1.59 ft at 10:30AM Sep 24, 2021Observed: 1.58 ft at 10:45AM Sep 24, 2021Observed: 1.58 ft at 11:00AM Sep 24, 2021Observed: 1.57 ft at 11:15AM Sep 24, 2021Observed: 1.56 ft at 11:30AM Sep 24, 2021Observed: 1.57 ft at 11:45AM Sep 24, 2021Observed: 1.58 ft at 12:00PM Sep 24, 2021Observed: 1.57 ft at 12:15PM Sep 24, 2021Observed: 1.57 ft at 12:30PM Sep 24, 2021Observed: 1.57 ft at 12:45PM Sep 24, 2021Observed: 1.56 ft at 1:00PM Sep 24, 2021Observed: 1.57 ft at 1:15PM Sep 24, 2021Observed: 1.57 ft at 1:30PM Sep 24, 2021Observed: 1.57 ft at 1:45PM Sep 24, 2021Observed: 1.56 ft at 2:00PM Sep 24, 2021Observed: 1.55 ft at 2:15PM Sep 24, 2021Observed: 1.56 ft at 2:30PM Sep 24, 2021Observed: 1.56 ft at 2:45PM Sep 24, 2021Observed: 1.56 ft at 3:00PM Sep 24, 2021Observed: 1.56 ft at 3:15PM Sep 24, 2021Observed: 1.56 ft at 3:30PM Sep 24, 2021Observed: 1.56 ft at 3:45PM Sep 24, 2021Observed: 1.55 ft at 4:00PM Sep 24, 2021Observed: 1.55 ft at 4:15PM Sep 24, 2021Observed: 1.55 ft at 4:30PM Sep 24, 2021Observed: 1.55 ft at 4:45PM Sep 24, 2021Observed: 1.55 ft at 5:00PM Sep 24, 2021Observed: 1.55 ft at 5:15PM Sep 24, 2021Observed: 1.55 ft at 5:30PM Sep 24, 2021Observed: 1.55 ft at 5:45PM Sep 24, 2021Observed: 1.55 ft at 6:00PM Sep 24, 2021Observed: 1.55 ft at 6:15PM Sep 24, 2021Observed: 1.55 ft at 6:30PM Sep 24, 2021Observed: 1.54 ft at 6:45PM Sep 24, 2021Observed: 1.54 ft at 7:00PM Sep 24, 2021Observed: 1.54 ft at 7:15PM Sep 24, 2021Observed: 1.54 ft at 7:30PM Sep 24, 2021Observed: 1.53 ft at 7:45PM Sep 24, 2021Observed: 1.53 ft at 8:00PM Sep 24, 2021Observed: 1.53 ft at 8:15PM Sep 24, 2021Observed: 1.53 ft at 8:30PM Sep 24, 2021Observed: 1.53 ft at 8:45PM Sep 24, 2021Observed: 1.53 ft at 9:00PM Sep 24, 2021Observed: 1.52 ft at 9:15PM Sep 24, 2021Observed: 1.52 ft at 9:30PM Sep 24, 2021Observed: 1.52 ft at 9:45PM Sep 24, 2021Observed: 1.52 ft at 10:00PM Sep 24, 2021Observed: 1.52 ft at 10:15PM Sep 24, 2021Observed: 1.52 ft at 10:30PM Sep 24, 2021Observed: 1.52 ft at 10:45PM Sep 24, 2021Observed: 1.52 ft at 11:00PM Sep 24, 2021Observed: 1.52 ft at 11:15PM Sep 24, 2021Observed: 1.52 ft at 11:30PM Sep 24, 2021Observed: 1.52 ft at 11:45PM Sep 24, 2021Observed: 1.52 ft at 12:00AM Sep 25, 2021Observed: 1.52 ft at 12:15AM Sep 25, 2021Observed: 1.52 ft at 12:30AM Sep 25, 2021Observed: 1.52 ft at 12:45AM Sep 25, 2021Observed: 1.52 ft at 1:00AM Sep 25, 2021Observed: 1.52 ft at 1:15AM Sep 25, 2021Observed: 1.52 ft at 1:30AM Sep 25, 2021Observed: 1.52 ft at 1:45AM Sep 25, 2021Observed: 1.51 ft at 2:00AM Sep 25, 2021Observed: 1.51 ft at 2:15AM Sep 25, 2021Observed: 1.51 ft at 2:30AM Sep 25, 2021Observed: 1.51 ft at 2:45AM Sep 25, 2021Observed: 1.51 ft at 3:00AM Sep 25, 2021Observed: 1.51 ft at 3:15AM Sep 25, 2021Observed: 1.51 ft at 3:30AM Sep 25, 2021Observed: 1.51 ft at 3:45AM Sep 25, 2021Observed: 1.51 ft at 4:00AM Sep 25, 2021Observed: 1.5 ft at 4:15AM Sep 25, 2021Observed: 1.5 ft at 4:30AM Sep 25, 2021Observed: 1.5 ft at 4:45AM Sep 25, 2021Observed: 1.5 ft at 5:00AM Sep 25, 2021Observed: 1.5 ft at 5:15AM Sep 25, 2021Observed: 1.5 ft at 5:30AM Sep 25, 2021Observed: 1.5 ft at 5:45AM Sep 25, 2021Observed: 1.5 ft at 6:00AM Sep 25, 2021Observed: 1.5 ft at 6:15AM Sep 25, 2021Observed: 1.5 ft at 6:30AM Sep 25, 2021Observed: 1.5 ft at 6:45AM Sep 25, 2021Observed: 1.5 ft at 7:00AM Sep 25, 2021Observed: 1.5 ft at 7:15AM Sep 25, 2021Observed: 1.5 ft at 7:30AM Sep 25, 2021Observed: 1.5 ft at 7:45AM Sep 25, 2021Observed: 1.5 ft at 8:00AM Sep 25, 2021Observed: 1.5 ft at 8:15AM Sep 25, 2021Observed: 1.5 ft at 8:30AM Sep 25, 2021Observed: 1.5 ft at 8:45AM Sep 25, 2021Observed: 1.5 ft at 9:00AM Sep 25, 2021Observed: 1.5 ft at 9:15AM Sep 25, 2021Observed: 1.5 ft at 9:30AM Sep 25, 2021Observed: 1.5 ft at 9:45AM Sep 25, 2021Observed: 1.5 ft at 10:00AM Sep 25, 2021Observed: 1.5 ft at 10:15AM Sep 25, 2021Observed: 1.5 ft at 10:30AM Sep 25, 2021Observed: 1.49 ft at 10:45AM Sep 25, 2021Observed: 1.5 ft at 11:00AM Sep 25, 2021Observed: 1.49 ft at 11:15AM Sep 25, 2021Observed: 1.48 ft at 11:30AM Sep 25, 2021Observed: 1.49 ft at 11:45AM Sep 25, 2021Observed: 1.51 ft at 12:00PM Sep 25, 2021Observed: 1.5 ft at 12:15PM Sep 25, 2021Observed: 1.5 ft at 12:30PM Sep 25, 2021Observed: 1.5 ft at 12:45PM Sep 25, 2021Observed: 1.5 ft at 1:00PM Sep 25, 2021Observed: 1.5 ft at 1:15PM Sep 25, 2021Observed: 1.5 ft at 1:30PM Sep 25, 2021Observed: 1.49 ft at 1:45PM Sep 25, 2021Observed: 1.48 ft at 2:00PM Sep 25, 2021Observed: 1.49 ft at 2:15PM Sep 25, 2021Observed: 1.49 ft at 2:30PM Sep 25, 2021Observed: 1.5 ft at 2:45PM Sep 25, 2021Observed: 1.5 ft at 3:00PM Sep 25, 2021Observed: 1.5 ft at 3:15PM Sep 25, 2021Observed: 1.5 ft at 3:30PM Sep 25, 2021Observed: 1.49 ft at 3:45PM Sep 25, 2021Observed: 1.49 ft at 4:00PM Sep 25, 2021Observed: 1.49 ft at 4:15PM Sep 25, 2021Observed: 1.48 ft at 4:30PM Sep 25, 2021Observed: 1.48 ft at 4:45PM Sep 25, 2021Observed: 1.48 ft at 5:00PM Sep 25, 2021Observed: 1.48 ft at 5:15PM Sep 25, 2021Observed: 1.49 ft at 5:30PM Sep 25, 2021Observed: 1.49 ft at 5:45PM Sep 25, 2021Observed: 1.49 ft at 6:00PM Sep 25, 2021Observed: 1.49 ft at 6:15PM Sep 25, 2021Observed: 1.49 ft at 6:30PM Sep 25, 2021Observed: 1.49 ft at 6:45PM Sep 25, 2021Observed: 1.48 ft at 7:00PM Sep 25, 2021Observed: 1.48 ft at 7:15PM Sep 25, 2021Observed: 1.48 ft at 7:30PM Sep 25, 2021Observed: 1.48 ft at 7:45PM Sep 25, 2021Observed: 1.48 ft at 8:00PM Sep 25, 2021Observed: 1.47 ft at 8:15PM Sep 25, 2021Observed: 1.47 ft at 8:30PM Sep 25, 2021Observed: 1.47 ft at 8:45PM Sep 25, 2021Observed: 1.47 ft at 9:00PM Sep 25, 2021Observed: 1.47 ft at 9:15PM Sep 25, 2021Observed: 1.47 ft at 9:30PM Sep 25, 2021Observed: 1.46 ft at 9:45PM Sep 25, 2021Observed: 1.47 ft at 10:00PM Sep 25, 2021Observed: 1.46 ft at 10:15PM Sep 25, 2021Observed: 1.46 ft at 10:30PM Sep 25, 2021Observed: 1.46 ft at 10:45PM Sep 25, 2021Observed: 1.46 ft at 11:00PM Sep 25, 2021Observed: 1.46 ft at 11:15PM Sep 25, 2021Observed: 1.46 ft at 11:30PM Sep 25, 2021Observed: 1.46 ft at 11:45PM Sep 25, 2021Observed: 1.46 ft at 12:00AM Sep 26, 2021Observed: 1.46 ft at 12:15AM Sep 26, 2021Observed: 1.46 ft at 12:30AM Sep 26, 2021Observed: 1.46 ft at 12:45AM Sep 26, 2021Observed: 1.46 ft at 1:00AM Sep 26, 2021Observed: 1.46 ft at 1:15AM Sep 26, 2021Observed: 1.46 ft at 1:30AM Sep 26, 2021Observed: 1.46 ft at 1:45AM Sep 26, 2021Observed: 1.46 ft at 2:00AM Sep 26, 2021Observed: 1.46 ft at 2:15AM Sep 26, 2021Observed: 1.46 ft at 2:30AM Sep 26, 2021Observed: 1.46 ft at 2:45AM Sep 26, 2021Observed: 1.46 ft at 3:00AM Sep 26, 2021Observed: 1.46 ft at 3:15AM Sep 26, 2021Observed: 1.46 ft at 3:30AM Sep 26, 2021Observed: 1.46 ft at 3:45AM Sep 26, 2021Observed: 1.46 ft at 4:00AM Sep 26, 2021Observed: 1.46 ft at 4:15AM Sep 26, 2021Observed: 1.46 ft at 4:30AM Sep 26, 2021Observed: 1.46 ft at 4:45AM Sep 26, 2021Observed: 1.46 ft at 5:00AM Sep 26, 2021Observed: 1.46 ft at 5:15AM Sep 26, 2021Observed: 1.46 ft at 5:30AM Sep 26, 2021Observed: 1.46 ft at 5:45AM Sep 26, 2021Observed: 1.46 ft at 6:00AM Sep 26, 2021Observed: 1.46 ft at 6:15AM Sep 26, 2021Observed: 1.46 ft at 6:30AM Sep 26, 2021Observed: 1.46 ft at 6:45AM Sep 26, 2021Observed: 1.46 ft at 7:00AM Sep 26, 2021Observed: 1.46 ft at 7:15AM Sep 26, 2021Observed: 1.46 ft at 7:30AM Sep 26, 2021Observed: 1.46 ft at 7:45AM Sep 26, 2021Observed: 1.46 ft at 8:00AM Sep 26, 2021Observed: 1.46 ft at 8:15AM Sep 26, 2021Observed: 1.46 ft at 8:30AM Sep 26, 2021Observed: 1.46 ft at 8:45AM Sep 26, 2021Observed: 1.46 ft at 9:00AM Sep 26, 2021Observed: 1.46 ft at 9:15AM Sep 26, 2021Observed: 1.46 ft at 9:30AM Sep 26, 2021Observed: 1.46 ft at 9:45AM Sep 26, 2021Observed: 1.47 ft at 10:00AM Sep 26, 2021Observed: 1.46 ft at 10:15AM Sep 26, 2021Observed: 1.46 ft at 10:30AM Sep 26, 2021Observed: 1.46 ft at 10:45AM Sep 26, 2021Observed: 1.46 ft at 11:00AM Sep 26, 2021Observed: 1.46 ft at 11:15AM Sep 26, 2021Observed: 1.46 ft at 11:30AM Sep 26, 2021Observed: 1.45 ft at 11:45AM Sep 26, 2021Observed: 1.47 ft at 12:00PM Sep 26, 2021Observed: 1.46 ft at 12:15PM Sep 26, 2021Observed: 1.46 ft at 12:30PM Sep 26, 2021Observed: 1.46 ft at 12:45PM Sep 26, 2021Observed: 1.46 ft at 1:00PM Sep 26, 2021Observed: 1.46 ft at 1:15PM Sep 26, 2021Observed: 1.47 ft at 1:30PM Sep 26, 2021Observed: 1.47 ft at 1:45PM Sep 26, 2021Observed: 1.45 ft at 2:00PM Sep 26, 2021Observed: 1.45 ft at 2:15PM Sep 26, 2021Observed: 1.46 ft at 2:30PM Sep 26, 2021Observed: 1.47 ft at 2:45PM Sep 26, 2021Observed: 1.46 ft at 3:00PM Sep 26, 2021Observed: 1.46 ft at 3:15PM Sep 26, 2021Observed: 1.46 ft at 3:30PM Sep 26, 2021Observed: 1.46 ft at 3:45PM Sep 26, 2021Observed: 1.46 ft at 4:00PM Sep 26, 2021Observed: 1.46 ft at 4:15PM Sep 26, 2021Observed: 1.45 ft at 4:30PM Sep 26, 2021Observed: 1.45 ft at 4:45PM Sep 26, 2021Observed: 1.46 ft at 5:00PM Sep 26, 2021Observed: 1.45 ft at 5:15PM Sep 26, 2021Observed: 1.46 ft at 5:30PM Sep 26, 2021Observed: 1.46 ft at 5:45PM Sep 26, 2021Observed: 1.46 ft at 6:00PM Sep 26, 2021Observed: 1.46 ft at 6:15PM Sep 26, 2021Observed: 1.46 ft at 6:30PM Sep 26, 2021Observed: 1.46 ft at 6:45PM Sep 26, 2021Observed: 1.46 ft at 7:00PM Sep 26, 2021Observed: 1.46 ft at 7:15PM Sep 26, 2021Observed: 1.45 ft at 7:30PM Sep 26, 2021Observed: 1.45 ft at 7:45PM Sep 26, 2021Observed: 1.45 ft at 8:00PM Sep 26, 2021Observed: 1.44 ft at 8:15PM Sep 26, 2021Observed: 1.44 ft at 8:30PM Sep 26, 2021Observed: 1.44 ft at 8:45PM Sep 26, 2021Observed: 1.44 ft at 9:00PM Sep 26, 2021Observed: 1.44 ft at 9:15PM Sep 26, 2021Observed: 1.44 ft at 9:30PM Sep 26, 2021Observed: 1.44 ft at 9:45PM Sep 26, 2021Observed: 1.44 ft at 10:00PM Sep 26, 2021Observed: 1.44 ft at 10:15PM Sep 26, 2021Observed: 1.44 ft at 10:30PM Sep 26, 2021Observed: 1.44 ft at 10:45PM Sep 26, 2021Observed: 1.44 ft at 11:00PM Sep 26, 2021Observed: 1.44 ft at 11:15PM Sep 26, 2021Observed: 1.44 ft at 11:30PM Sep 26, 2021Observed: 1.44 ft at 11:45PM Sep 26, 2021Observed: 1.44 ft at 12:00AM Sep 27, 2021Observed: 1.44 ft at 12:15AM Sep 27, 2021Observed: 1.44 ft at 12:30AM Sep 27, 2021Observed: 1.44 ft at 12:45AM Sep 27, 2021Observed: 1.44 ft at 1:00AM Sep 27, 2021Observed: 1.44 ft at 1:15AM Sep 27, 2021Observed: 1.44 ft at 1:30AM Sep 27, 2021Observed: 1.44 ft at 1:45AM Sep 27, 2021Observed: 1.44 ft at 2:00AM Sep 27, 2021Observed: 1.44 ft at 2:15AM Sep 27, 2021Observed: 1.44 ft at 2:30AM Sep 27, 2021Observed: 1.44 ft at 2:45AM Sep 27, 2021Observed: 1.44 ft at 3:00AM Sep 27, 2021Observed: 1.44 ft at 3:15AM Sep 27, 2021Observed: 1.44 ft at 3:30AM Sep 27, 2021Observed: 1.44 ft at 3:45AM Sep 27, 2021Observed: 1.44 ft at 4:00AM Sep 27, 2021Observed: 1.44 ft at 4:15AM Sep 27, 2021Observed: 1.44 ft at 4:30AM Sep 27, 2021Observed: 1.44 ft at 4:45AM Sep 27, 2021Observed: 1.44 ft at 5:00AM Sep 27, 2021Observed: 1.44 ft at 5:15AM Sep 27, 2021Observed: 1.44 ft at 5:30AM Sep 27, 2021Observed: 1.44 ft at 5:45AM Sep 27, 2021Observed: 1.44 ft at 6:00AM Sep 27, 2021Observed: 1.44 ft at 6:15AM Sep 27, 2021Observed: 1.44 ft at 6:30AM Sep 27, 2021Observed: 1.44 ft at 6:45AM Sep 27, 2021Observed: 1.44 ft at 7:00AM Sep 27, 2021Observed: 1.44 ft at 7:15AM Sep 27, 2021Observed: 1.44 ft at 7:30AM Sep 27, 2021Observed: 1.44 ft at 7:45AM Sep 27, 2021Observed: 1.45 ft at 8:00AM Sep 27, 2021Observed: 1.45 ft at 8:15AM Sep 27, 2021Observed: 1.45 ft at 8:30AM Sep 27, 2021Observed: 1.45 ft at 8:45AM Sep 27, 2021Observed: 1.44 ft at 9:00AM Sep 27, 2021Observed: 1.44 ft at 9:15AM Sep 27, 2021Observed: 1.44 ft at 9:30AM Sep 27, 2021Observed: 1.45 ft at 9:45AM Sep 27, 2021Observed: 1.45 ft at 10:00AM Sep 27, 2021Observed: 1.45 ft at 10:15AM Sep 27, 2021Observed: 1.44 ft at 10:30AM Sep 27, 2021Observed: 1.44 ft at 10:45AM Sep 27, 2021Observed: 1.45 ft at 11:00AM Sep 27, 2021Observed: 1.45 ft at 11:15AM Sep 27, 2021Observed: 1.43 ft at 11:30AM Sep 27, 2021Observed: 1.44 ft at 11:45AM Sep 27, 2021Observed: 1.45 ft at 12:00PM Sep 27, 2021Observed: 1.45 ft at 12:15PM Sep 27, 2021Observed: 1.46 ft at 12:30PM Sep 27, 2021Observed: 1.46 ft at 12:45PM Sep 27, 2021Observed: 1.46 ft at 1:00PM Sep 27, 2021Observed: 1.46 ft at 1:15PM Sep 27, 2021Observed: 1.45 ft at 1:30PM Sep 27, 2021Observed: 1.44 ft at 1:45PM Sep 27, 2021Observed: 1.44 ft at 2:00PM Sep 27, 2021Observed: 1.44 ft at 2:15PM Sep 27, 2021Observed: 1.45 ft at 2:30PM Sep 27, 2021Observed: 1.45 ft at 2:45PM Sep 27, 2021Observed: 1.45 ft at 3:00PM Sep 27, 2021USGS--Water Resources of the United StatesGMRM2(plotting HGIRG) Graph Created (3:40PM Sep 27, 2021)ObservedLatest observed value: 1.45 ft at 3:00 PM EDT 27-Sep-2021. Flood Stage is 6 ft
Printable Image
About this graph
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.
Return to Area Map
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) 11.57 ft on 08/04/2020
(2) 7.45 ft on 07/08/2019 (P)
(3) 6.00 ft on 11/25/2018
(4) 6.19 ft on 07/22/2018
(5) 7.90 ft on 05/20/2018
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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Gauge LocationGauge Map Marker
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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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