Properly Measuring Water The White River Valley has been fortunate if not lucky that there has never been a call on the White River. It is a matter of time before the river is placed under a call and users need to have proper measuring devices so that they can continue to use the water that has been adjudicated to them. Piceance Creek basin water users understand the implications of a call and how improper measuring devices effect even the most senior of users and that legally they will be restricted from using their water. The following is a brief glimpse of the types of measuring devices that you can use, how a proper measuring devise will function and what that looks like, and finally followed by a list of resources for purchasing, installing, and design of measuring devices. Types of Measuring Devises The list of measuring devices found within this article are not all inclusive, rather the article is focusing on the three most common types of measuring devices. (Weirs, Flumes, and Current Meters). All of the following information is taken from the Bureau of Reclamation (BOR), "Water Measuring Manual" unless otherwise noted. These devices are approved by the Bureau Reclamation and Colorado Division of Water resources (CDWR), division engineer. It is important to know that the CDWR engineer for each water division within the state approves the measuring devices, but there is a another level of approval and that each ditch company has the right to say which devices they will choose to use from the list of those approved by CDWR. Weir A measuring weir is simply an overflow structure built perpendicular to an open axis to measuring the rate of flow of water. Inspecting and checking the critical parts of weir structures for degradation and improper operation are easy. Weirs are commonly named by the shape of their blade overflow opening shape for sharp-crested weirs or the flow control section shape for broad-crested weirs. Thus, weirs are partially classified as rectangular, trapezoidal, triangular etc. Flumes Flumes are shaped, open-channel flow sections that force flow to accelerate. Acceleration is produced by converging the sidewalls, raising the bottom, or a combination of both. When only the bottom is raided with no side contractions, the flume is commonly called a broad-crested weir. Current Metering Current meters, commonly referred to as flow meters, are velocity measuring devices that sample at a point. Each point velocity measurement is then assigned to a meaningful part of the entire cross section passing flow. The velocity-area principal is used to compute discharge from current-meter data. Total discharge is determined by summation of partial discharges. Dtat are usually determined over a useful range of total discharges. These discharges are related to measurement water surface elevations related to a fixed head measuring device to provide a rating curve. After full confidence in the rating is attained, the calibrated head measurement device and cross section may be used as a gaging station.