Water Measurement

Guidelines and procedures for collecting water measurement data and reporting the information to the Idaho Department of Water Resources have been developed in order to have an orderly and uniform measuring and reporting program within the State of Idaho.

The information below assists in measuring and reporting diversions pursuant to various water measurement orders issued by IDWR. The following links and guidelines are also applicable and useful for water measurement requirements within water districts.

Measurement Guidelines

Flow Meter Certification

Ultrasonic or Magnetic Flow Meter Certification

Small Diameter Flow Meter Certification

Publications and Media

Measurement Data Resources

Water Measurement Information Systems (WMIS)

The WMIS and Water District Diversion Data applications are used by IDWR, watermasters, and district hydrographers to enter and retrieve delivery measurements and estimations of annual water usage. The WMIS database primarily contains information related to irrigation wells on the Eastern Snake River Plain Aquifer, but it is also used for other ground and surface water points of diversion for which annual delivery totals are recorded. The Water District Diversion Data database contains daily diversion records for certain surface water diversions and some ground water diversions for which regular flow rate measurements are taken. For further information, please contact the Water Distribution Section at (208) 287-4958.


Related Information:


  • 42-701 - General statutory requirement for water measurement and reporting in Idaho.

Water Conversion Factors:

  • Water Conversion Factors (printable)

    1 Miner's Inch =
    9 gallons per minute or 0.02 CFS
    1 Cubic Foot of Water =
    7.4805 gallons or 62.37 pounds
    1 Cubic Foot per Second (CFS) =
    448.83 gallons per minute or 26,930 gallons per hour or 646,315 gallons per day
    1 Cubic Foot per Second (CFS) =
    1.9835 AF per day - 59.505 AF per 30 days - 723.9775 AF per year
    1 Acre-Foot (AF) =
    enough water to cover 1 acre of land one foot deep
    1 Acre-Foot =
    43,560 cubic feet or 325,850 gallons
    1 Cubic Meter per Second =
    35.31 CFS or 15,850 gallons per minute
    1 Million Gallons =
    3.0689 acre-feet
    1 Million Gallons Per Day =
    1,120.147 acre-feet per year
    10 Cents Per 1,000 Gallons =
    $32.59 Per AF