Flow monitor provides accurate reports
Problem
Dry-weather influent at the 4 mgd Sandy Beach Treatment Plant on Oahu, Hawaii, fluctuated from 0.2 to 10 mgd with velocity from less than 0.10 to 3.5 feet per second. Flow monitors just downstream from a rectangular channel feeding a 36-inch concrete pipe produced unreliable readings, resulting in excessive explanatory reporting to the state Department of Health.
Solution
The plant superintendent looked for a reliable unit that would require little operator attention, integrate with the SCADA system, and trigger the wastewater sampler on accurate flow-weighted intervals to meet regulatory obligations. Plant staff did comparative testing that included a
