USGS Hydrologic Instrumentation Facility
Water Data for the Nation
ABOUT THE HIF
USGS IN YOUR STATE
USGS Water Science Centers are located in each state.
Facilities at the Hydrologic Instrumentation Facility
The Hydraulic Laboratory is a one-of-a-kind facility within the United States. Meters, flumes, and other flow-measuring devices are evaluated and calibrated at the laboratory before being used by USGS offices and other Federal and State Agencies. Standards are also developed that affect USGS operations nationwide. It also used in water-resources investigations and to obtain experimental data used in research studies on the mechanics of flow and the transport and dispersion of heat, solutes, and solids in rivers and estuaries.
Sized at 12 x 12 x 450 ft, it is used to test and calibrate instruments that measure water velocity by the principle of cup rotation, drag, Doppler effect, acoustic signal, electromagnetic field, deflection, or other means. The tow vehicle is capable of speeds from 0 to 18 feet per second (ft/s) and has a platform size of 12 x 14 ft. The carriage is equipped with a data acquisition system designed to accept distance traveled, elapsed time, and meter pulse count information.
SUBMERGED JET TANK
Built as a 12 x 12 ft cross section and is 120 ft long. The tank provides a low turbulence, live-velocity source; that is, the water moves past the stationary meter. The discharge into the tank flows from the constant head tank to the head box of the jet, through the jet, over a weir, and back to the sump from which pumps convey the water back to the constant head tank. The system allows for a discharge stable to less than 0.5 percent. Discharge measurements are made using calibrated volumetric tanks. Velocities of the 2-ft diameter jet have a stable range of 0.25 to 8 ft/s.
LARGE ACOUSTIC TANK
The large acoustic meter tow tank is a 4 ft wide, 4 ft deep, 80 ft long tank with a carriage that travels on rails mounted above the tank's side wall. The carriage can travel at velocities ranging from 0.1 to 3 ft/s ( 0.03 to 0.91 m/s). Constant water velocity is simulated by suspending the meter from the tow carriage into the still water of the tank and moving the carriage at a constant velocity.
SMALL ACOUSTIC TANK
The small acoustic meter tow tank is a 3 ft wide, 3 ft deep, 9 ft long tank with a carriage that travels on rails mounted above the tank's side wall. The carriage can travel at velocities ranging from 0.59 to 1.5 ft/s (0.18 to 0.46 m/s). Constant water velocity is simulated by suspending the meter from the tow carriage into the still water of the tank and moving the carriage at a constant velocity. The accuracy limit for any run velocity as computed from the time measured by the tank’s data acquisition system to traverse the reference distance is: VLimit = VMeasured * 0.001 VMeasured.
CONSTANT HEAD TANK
All flowing water within the Laboratory are supplied by a constant-head tank. This 62,000 gallon tank measures 24 feet high, 21 ft 6in in diameter, and has 216 linear feet of weir surface.
The tilting flume is 6 ft wide, 3 ft deep and 250 ft long and can be tilted to a slope of 1 percent. The discharge capacity is a maximum of 50 cubic feet per second (cfs), partially or wholly supplied by the laboratory's constant head tank. The whole discharge can be recirculated, hence it is adequate for sediment work.