What is the standard water measuring device for the Colorado Division of Water Resources (DWR)? There are several other types of measuring devices, including electronic flow meters, but the Parshall Flume is most commonly used.
A Parshall Flume might be the most recognizable measuring device readily available. With an hourglass shape from the top, the Parshall Flume is quickly identified and easy to install. However, there are several things to watch for while using this flume. The ditch immediately above the device should be clear of things like culverts, gates, and other obstructions. The ditch should be wider and deeper than the flume. The flume itself should be level in all directions and the floor be at least four inches higher than the ditch bottom.
A weir is another option. It is more commonly used in narrower or smaller diversions. Rectangular and V-notch weirs are the two most common. During installation, the centerline of the weir should be placed parallel to the direction of the water flow and high enough to allow water to fall off, while creating a small air gap underneath. Weirs should also be level to allow for a uniform water flow over them, across the width of the weir.
The DWR Division 6 Engineer, Erin Light, required that all water users have an operational measuring device in place by July 31, 2020, to be in compliance. Erin confirmed today that the date has been extended to Oct. 31, 2020. More information on the requirements from DWR and how to install measuring devices from the Natural Resources Conservation Service (NRCS) can be found on the DWR’s website and the Districts’ website at http://www.whiterivercd.com/measuring-devices.html.