USGS Water-Year Summary 2024

16809600 La Sa Fua River near Umatac, Guam

LOCATION - Lat 13°18'25.0", long -144°95'1.9" referenced to North American Datum of 1983, Guam County, GM, Hydrologic Unit 22010000, on left bank 0.6 mi north of Sanchez school in Umatac, and 0.8 mi upstream from mouth.

DRAINAGE AREA - 1.03 mi². from automated delineation using 5-meter digital elevation model, using UTM Zone 55N projection, NAD83 HARN horizontal datum. The 5-m digital elevation model was derived from a digital terrain model, created by Joint Airborne Lidar Bathymetry Technical Center of Expertise, dated May 2007.

REVISIONS HISTORY - WDR HI-10-1: Drainage Area.

SURFACE-WATER RECORDS

PERIOD OF RECORD - April 1953 to July 1960, October 1976 to April 1984, June 2000 to current year. Prior to October 1976, published as Fouha River near Umatac. From June 2000 to September 2005, unpublished records are in the files of the U.S. Geological Survey.

GAGE - Water-stage recorder and concrete control. Altitude of gage is 120 ft above mean sea level (from topographic map). Prior to June 2000, at datum 10 ft higher.

REMARKS - No known diversions upstream.

EXTREMES FOR PERIOD OF RECORD - Maximum discharge, 2,300 ft³/s, November 23, 2020, gage height 17.16 ft.  Maximum gage height, 17.73 ft, July 5, 2002 discharge 2,140 ft³/s, from rating curve extended above 320 ft³/s on basis of slope-area measurements at gage heights 17.73 ft; minimum 0.12 ft³/s, June 13, 1979, during short regulation of flow at diversion upstream.

WATER-QUALITY RECORDS

PERIOD OF RECORD - October 2005 to September 2011 (discontinued).

PERIOD OF DAILY RECORD - SUSPENDED-SEDIMENT DISCHARGE: October 2005 to September 2011 (discontinued).

EXTREMES FOR PERIOD OF RECORD - SUSPENDED SEDIMENT CONCENTRATION: Maximum daily mean observed, 2,270 mg/L, August 18, 2007; minimum, 0.0 mg/L on many days. SUSPENDED SEDIMENT DISCHARGE: maximum daily mean observed, 859 tons, December 2, 2009; minimum, 0.00 tons on many days.