EP 1110-1-27
27 Jan 00
(1) Water-level measurement recommendations include:
Water-level data may be collected manually or the process automated.
For relatively small numbers of wells and conditions where personnel are not at health risk
when water columns are exposed, electric water-level probe and manual data entry may be
used.
For larger numbers of wells where personnel time would be inordinately devoted to water-
level measurements, instrumented airline or automated water level recording via transducers
is recommended.
For conditions where exposure to vapors off-gassing from well fluids poses an inhalation hazard,
instrumented airline or automated water-level recording via transducers is recommended. Several
approaches to water-level measurement are possible, each with its advantages and disadvantages. Table 2-
3 summarizes these features.
(2) For flow measurements, each pumping well and receiving well or discharge should be
metered. Total system pumping production should match total discharge. Imbalances may indicate leaks
or metering inaccuracies.
(a) Flow meters should be sized to the expected flow. Instantaneous and totalized flow readings in
commonly used volume-rate units (cubic meters/hour, gal/min, etc.) are necessary.
(b) Flow measurement method selections should take into consideration the quality of the fluid to
be measured. High-solids, biofouling, or scaling water streams may foul turbine flow meters (TM 5-813-
5, TI 814-3). Acoustic devices may have better service lives under some circumstances. Systems standard
to industrial waste water treatment applications should suffice.
(c) At a minimum, measurements should be taken manually daily to weekly, depending upon
fluctuation.
(d) Wherever possible, flow meters should have automatic readouts, either to a central SCADA
system or readout device. Systems standard to industrial water supply should suffice. Calibrate the
equipment at the frequency recommended by the manufacturer.
(3) For pressure measurement, either manually read or digital read-out meters may be used. With
both, plugging of sensor orifices is to be expected. To detect pressure changes in the conveyance system,
pressure should be measured as near as possible to the wellhead (immediately downstream of the pump
discharge check valve). Measurements should be taken daily to weekly. Automation facilitates data
collection.
(4) For electrical (power), measure changes in pump motor amperage (A) draw, circuit voltage
(V), and resistance ohms (Ω) to detect problems in the electrical system. Portable equipment should be
available for testing purposes.
(a) Voltage should be within +10 percent of the motor nameplate voltage when the motor is under
load (running). Larger voltage variations may cause winding damage. These variations should be
corrected in the power supply or the motor replaced to match the supplied voltage characteristics if the
voltage remains constantly high or low.
2-11
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