Or. Admin. Code § 690-217-0045 - Acceptable Techniques for Measurement of Water Level and Discharge

(1) Water level measurements shall be taken by one of the following methods:

(a) An electric water level measuring tape specifically designed for this purpose. Depth markings on the tape shall be no more than five feet apart, and shall be accurate to 0.5 percent. All water level measurements shall be reported to a precision of at least one-tenth of a foot;

(b) A calibrated electronic pressure transducer coupled with an appropriate output device or data logger. The accuracy and precision of the transducer and output device or data logger shall meet those outlined in subsection (1)(a) of this rule for electric water level measuring tapes. If an electronic pressure transducer is used for water level measurement, the manufacturer's name, the serial number and calibration date of the device must be supplied in the pump test report;

(c) An air line and pressure gauge. Air line measurements shall be accepted only where water levels deeper than 300 feet below ground level are encountered or expected. Air line accuracy shall be verified by at least one water level measurement with an electric water level measuring tape;

(d) An acoustic sounding device designed and manufactured specifically for measuring the depth to water in walls;

(e) The wetted steel tape method. This method may be used for static water level measurements only.

(2) Measurements of air line pressure of shut-in pressure of flowing artesian wells shall be with a calibrated pressure gauge with marked intervals of one PSI or less.

(3) Discharge from the pump shall be physically measured by a standard and acceptable method. In no case will visually estimated flow rates be accepted. Acceptable methods include:

(a) A properly installed flow meter which is functional and calibrated within reasonable limits;

(b) A properly installed weir or flume;

(c) A properly installed calibrated orifice plate and manometer;

(d) Known volume/time calculations (including calibrated bucket and stopwatch up to 60 gallons per minute); and

(e) Properly used ultrasonic flow measuring devices.

Notes

Or. Admin. Code § 690-217-0045

WRD 25-1988, f. & cert. ef. 12-20-88