Case Study: The Town Of Walden Responds To Changing Measurement Needs

By Mark Russell Water and Wastewater Superintendent The Town of Walden

As is the case in many municipalities these days, The Town of Walden’s water treatment plant needs changed over time. The town found it now had a requirement to measure finished water. The town’s original pump station design did not include a flow meter. The town also had two common problems faced by municipalities when specifying and installing a retrofit flow meter for a finished water application: 1) limited real estate and space requirements and 2) a need for high accuracy flow measurement. Added to that was another common challenge for local governments—the need to minimize both installation costs and ongoing maintenance costs for any new technology solution.

Typically, traditional liquid flow meters require a minimum upstream and downstream straight pipe run in order to operate effectively and accurately. Most traditional flow meter installations require 10 to more than 40 straight pipe diameters upstream from the meter and five or more straight pipe diameters downstream. These straight pipe runs are required in order to eliminate the effects of swirl and other pipeline disturbances caused by pumps, elbows, valves and other devices that negatively affect liquid flow measurement accuracy.

Working together, the town’s engineers and Canyon Systems evaluated multiple flow measurement options suited for municipal water system applications. The McCrometer V2 System™ Municipal Flow Meter was high on the list of considered instrument options because of its high accuracy, flexible installation requirements and versatile capabilities. It is a differential pressure (DP) type flow meter with a design that includes a self-conditioning cone within the meter.

This unique DP type flow meter is especially useful when irregular or crowded piping and equipment are in place because its self-conditioning cone design greatly reduces the straight piperun required for accurate measurement. Other flow technologies, such as orifice plate, turbine or venturi tube meters, often require complex or expensive construction in the area where the flow meter will be installed in order to install the upstream and downstream straight piping required to achieve the desired measurement accuracy.