A buyer’s guide to open channel and full-pipe flow meters, covering portable vs permanent monitoring, MCERTS, ATEX, and buy or hire options.
Selecting the right flow meter depends on your site conditions, measurement duration, and compliance requirements. This guide explains the practical choices between open-channel and full-pipe measurement, portable and permanent monitoring, contact and non-contact technology, and whether to buy or hire, using Cura Terrae Water’s DuraTracker®, ISCO Signature®, and LaserFlow® flow meters as examples.
Open-Channel Flow Meters or Full-Pipe Measurement?
The right measurement approach depends on where your flow is taking place. Cura Terrae Water’s open-channel flow meters, full-pipe flow meters, flow sensors, and accessories are available to buy or hire, with MCERTS and ATEX filters to help you narrow down a suitable option for your site.
For open-channel applications, open channel flow measurement often uses a channel flow meter in several forms, including ultrasonic flow meters, Doppler, and radar, and the DuraTracker® Flow Meter is designed for short-term flow surveys requiring accurate, reliable data. It features bi-directional monitoring and is suited to complex and challenging flow conditions, including capturing the response of wastewater networks to precipitation events for numerical model development and validation.
The ISCO Signature® MCERTS Flow Meter is also designed for open channel flow monitoring applications, supporting standard open channel level-to-flow conversions as well as user-defined equations or level-to-flow data points, depending on the application need.
Portable or Permanent Monitoring?
Whether you need a short-term survey or long-term compliance monitoring will influence your choice of flow meter.
The DuraTracker® is suitable for both portable and permanent-site area velocity flow monitoring, making it a flexible option for inflow and infiltration studies, combined sewer overflow (CSO) monitoring, and other network and catchment-based studies. Area velocity measurement combines water velocity with depth to determine flow. Its low-profile Area Velocity sensor minimises flow stream obstructions and consistently measures and records flows at low flow levels. Permanent open-channel arrangements may also use a primary device such as a weir or flume, depending on the site.
For ongoing discharge compliance monitoring, the ISCO Signature® Flow Meter simultaneously collects data from multiple flow and water quality measurement devices, providing a comprehensive picture of your activities to help demonstrate regulatory compliance over time.
Contact or Non-Contact Technology?
Site access and environmental conditions often determine whether contact or non-contact measurement is the better fit.
The ISCO Signature® supports several measurement technologies, including the TIENet™ 350 Area Velocity Sensor, TIENet™ 330 Bubbler Module, TIENet™ 310 Ultrasonic Level Sensor, and TIENet™ 360 LaserFlow®. In installations that use a weir or flume, a level sensor relates liquid level to discharge; the right arrangement depends on the channel and application.
Where ragging or corrosive chemicals are a concern, or where manhole entry needs to be avoided, the ISCO TIENet™ 360 MCERTS LaserFlow® offers the advantages of non-contact measurement, with reduced corrosion and wear, less maintenance, suitability for hazardous areas, and less risk of blocking when a thick fluid is being measured. It uses a laser to penetrate the water’s surface, recording multiple sub-surface measurements to create a velocity profile of the flow cross-section, combined with non-contact ultrasonic readings to measure liquid level and calculate flow rate. Alternatively, an optional continuous-wave Doppler area velocity sensor can be installed to measure flow during surcharge conditions. The LaserFlow® integrates with both the ISCO Signature® and DuraTracker® flow meters as part of a comprehensive monitoring solution, and can be deployed and removed from above ground, avoiding confined space entry.
Buy or Hire?
Cura Terrae Water’s flow meters, sensors, and accessories are available to buy or hire. Hiring may suit short-term surveys, such as those using the DuraTracker® for capturing storm response data, while buying may be more appropriate for permanent, site-based compliance monitoring using the ISCO Signature®. The right choice depends on the duration and purpose of your monitoring project.
Data Integrity, MCERTS, and ATEX
Where regulatory scrutiny is a factor, data integrity features matter. The ISCO Signature® has unique features to verify data integrity, logging key events such as changes in calibration and power outages, so that records can be reviewed to detect any type of data alteration.
MCERTS accreditation applies to the ISCO Signature® MCERTS Flow Meter and the ISCO TIENet™ 360 MCERTS LaserFlow®, meeting Environment Agency standards. Where potentially hazardous environments are a consideration, both the DuraTracker® and the LaserFlow® are available as ATEX certified or non-ATEX, so your choice should reflect the classification of your site.
Frequently Asked Questions
Can the LaserFlow® be used on its own, or does it need another flow meter?
The LaserFlow® integrates with the ISCO Signature® and DuraTracker® flow meters as part of a comprehensive monitoring solution.
Is the DuraTracker® suitable for permanent installations?
Yes. The DuraTracker® is suitable for both portable and permanent-site area velocity flow monitoring, including inflow and infiltration studies and CSO monitoring.
Which flow meters support multi-parameter logging, such as pH and temperature?
The ISCO Signature® Flow Meter supports multi-parameter logging, including pH and temperature, alongside its flow measurement technologies.
How do I choose between contact and non-contact measurement?
The choice depends on site access, flow conditions and the monitoring objective. Area velocity technology may suit portable or permanent monitoring, while LaserFlow® provides a non-contact option where ragging, corrosive chemicals or confined-space access are concerns.
Should I buy or hire a flow meter?
Hiring can suit a short-term survey, while purchase may be more appropriate for permanent or repeated monitoring. Cura Terrae Water offers flow meters, sensors and accessories to buy or hire, so the decision can be matched to the duration and purpose of the project.
Speak to Cura Terrae Water
If you are weighing up open-channel versus full-pipe measurement, portable versus permanent monitoring, or contact versus non-contact technology, enquire about any of these products to discuss which option best suits your site conditions.
