City of Fontana Uses QS200 Flow Sensors for Public Spaces Water Conservation Project
The City of Fontana, California (pop. 200,000) has many landscaped traffic islands and median strips. The city has suffered severe droughts in recent years, and conserving water and maintaining valuable trees and shrubs in public spaces has been a major concern. The city's annual water usage budget is $250,000.
Many of the city's green areas on traffic islands use drip irrigation to water the plants and shrubs. City officials were monitoring water usage via paddle-wheel flow sensors attached to a remote alarm system. The paddle wheel flow sensors were ineffective because they continually gave false positives—showing "no flow" when the flow was below the sensor's threshold for sensing.
Paddle wheel sensors have an impeller that requires sufficient flow velocity to overcome the friction between the wheel and the shaft to sense flow. In low-flow situations, such as drip irrigation, paddle wheel sensors often cannot register low flow rates.
The ultrasonic QS200 flowmeter has no moving parts and requires much lower flow rates to register a reading. It "retrofits" into most leading irrigation systems.
The City installed the FLOMEC QS200 in a single installation with a bubbler head for drip irrigation, with flow below 3 GPM, retrofitting it into the existing housing. The low-flow alarms were reset on the QS200 ultrasonic flow meters.
A low-flow alarm from the QS200 occurred and was thought to be another false alarm, similar to those previously observed with the paddle wheel sensors. When the alarm was investigated, however, a blockage in the nozzle was found, and no water was reaching the meter or the plants.
The meter's ability to detect low flows, typical of bubbler head nozzles and drip line water velocities, saved the city the cost of replacing the greenery along the entire median strip—an expensive and difficult job when complicated by traffic flow. Savings were estimated by the City of Fontana Engineer in the thousands of dollars.
 QS200 can easily replace an existing paddlewheel flow sensor |
