Stage and Pore Pressure
A non-contact stage sensor (at left) is suspended approximately 2 meters above a pressure transducer mounted in the center of the channel bed.
NOTE: Data collection at the Gap File has been discontinued.
Stage at station 1 is measured by a non-contact radar distance meter suspended over the channel. The device measures the distance from the senor to the surface below. When no runoff is present, the measurement surface is the surface of the channel bed. Distance measurements are converted into a stage above an arbitrary datum. Changes in stage detected by the sensor when no runoff is present are usually caused by infilling of the channel by dry ravel processes.
Pressure transducers are used to measure fluid pressures in the pores of the bed directly beneath the stage gage. Two pressure transducers are buried side-by-side beneath approximately 15 cm of fine-grained bed material. Pressure is displayed as an equivalent depth of water in meters. The measurement includes pore water pressure and barometric pressure. Barometric pressure is measured by a separate instrument above the channel and has not been removed from the data displayed.
Stage, Pore Pressure, and Rainfall for Last 24 Hours
Stage, Pore Pressure, and Rainfall for Last Week
