The final determinations of PR19 stipulate that during AMP7 England and Wales water companies Outcome Delivery Incentives shall on average reduce Leakage by 16% and Supply Interruptions by 41% no later than 2025.

However, you can’t effectively manage Leakage if you’re reliant on outdated or unproven network flow models rather than real-time dynamic data. And more often than not, there’s no flow measurement where you need it. Or, you have an electromagnetic flow meter in place, but it’s long since reached end-of-life and hasn’t sent valuable flow data in who knows how long. But how to swap it out without a Supply Interruption?

So…The Mag Meter Replacer!

A provocative statement? Of course. But this article does not claim that Ultrasonic Clamp-On Flowmeters will be the replacement for all electromagnetic flowmeters across the board. Electromagnetic flowmeters are widely used across the industry and successfully provide thousands of flow measurement points across UK water networks. Furthermore, they can be battery powered and installed in the most remote of locations. So, mag meters have their rightful and valued place in the UK water industry for the foreseeable future.

Replacing Dead Mag Meters

How many “dead” flowmeters are there across the UK water networks? 100’s? More? Frequently meters have been installed on single pipelines with no isolation valves or bypass. Possibly in haste, possibly due to economic or planning permission constraints? Any mag meter that fails on such a pipe proves substantially challenging to replace because of the potential for interrupted water or wastewater production, supply interruption, inaccessibility, or even the escalating cost of standby wastewater tankers. Operating the site blind, reduces the operator’s capacity for network flow optimisation or even leakage detection, but nonetheless countless sites remain operationally blind due to a mag meter past it’s use-by date.

Technology You Can Trust

Ultrasonic clamp-on can be the answer. Forget those past tales of “clamp-on doesn’t work”, “it’s unreliable”, “it doesn’t work in the presence of solids”, etc. There’s clamp-on, and there’s FLEXIM FLUXUS clamp-on. Reliable, repeatable, MCERTed flow metering from the only clamp-on ultrasonic flow meter company approved for safety critical duties in the UK nuclear sector. The company that provides hydraulic flow leak detection that keeps you safe every time you fly on an Airbus worldwide.

FLUXUS clamp-on meters are available in 316ss, with IP68 rating for submerged use in flooded chambers. Also available ATEX rated for hazardous methane environments. And we have solutions for water or wastewater at flowrates from 0.01m/s to 25m/s in pipes from <50mm to 6.5m. Reverse flow detection and monitoring comes as standard, along with class-leading temperature-compensated transducers (meeting the requirements of ASME MFC-5.1–2011). We even provide FOC derived water temperature, a feature that provides potential warning of bacterial growth in unduly warm summers and possible advance indication of pipe freeze/thaw bursts during harsh winter weather.

Installation is a cinch; fit in the smallest of spaces during flowing conditions – due to factory pre-calibration there is no need to isolate or zero the flow. No cost for notifying local households of supply outages, no cost for skilled water company personnel to attend site, operate isolation valves, divert flows, use lifting gear, replace mag meter, etc. No costs for standby tankers, costs to flush the pipe after installation and & no consequential reputational issues for water discolouration. 


Network or plant metering restored, visibility and leakage monitoring improved, at lower “installed cost” than replacement mag meter and with zero supply interruption to clients. Not to mention the safety benefits: substantially reduced challenges working in confined space; quicker, simpler, easier and thus safer work, especially during Covid-19 conditions.

FLUXUS flowmeters can even be kept on hand as emergency flow replacements in the event of unexpected failure of a system-critical inline flowmeter.

For further information on how FLEXIM can deliver metering without supply interruption contact:

01606 781 420