USGS Water-Year Summary 2021
06463720 Niobrara River at Mariaville, Nebr.
LOCATION - Lat 42°46'50", long 99°20'23" referenced to North American Datum of 1983, Keya Paha County, NE, Hydrologic Unit 10150004, on upstream side of bridge, 13 mi North of Newport and 20.5 mi upstream from the mouth of the Keya Paha River.
DRAINAGE AREA - 9,810 mi². approximately.
PERIOD OF RECORD - October 1985 to September 1991 (water quality data only September 1985). May 2012 to September 2013 (seasonal record only), October 2013 to current year.
GAGE - Water-stage recorder with satellite telemetry. Elevation of gage is 1,797 ft above National Geodetic Vertical Datum of 1929, from topographic map.
EXTREMES FOR PERIOD OF RECORD - For water years 1986 to 1991, seasonal records for May 2012 to September 2013, and October 2013 to present. Maximum peak flow, 30,900 ft³/s, gage height, 7.72 ft, March 14, 2019. From rating curve extension above 6,060 ft³/s based on indirect measurement.