Range of ultrasonic sensors outperform hydrostatic sensors for measuring storm water runoff

Extreme weather events have shown the limitations of urban and rural infrastructure in terms of dealing with overflows that occur after heavy rains and other weather events. In Scandinavia, for example, the first steps in the logging process is not just the amount, but also the time and volume of individual overflows. That data is used not only to calculate the volume of unprocessed wastewater, but to measure its environmental impact as well. Most importantly, it is used to determine how much to expand sewage systems to accommodate overflows.

Pumping stations, overflow constructions and retention basins are important in keeping sewage water away from streets and the environment. When measuring sewage water levels in a well or overflow construction, hydrostatic instruments are exposed to sludge, leaves and other debris. The result can be faulty level measurement and pumps wasting power or not even being activated when needed, not to mention the hours spent cleaning or replacing equipment.

Ultrasonic level transmitters, on the other hand, are a widely recognised alternative to hydrostatic pressure level measurement for storm water applications. AMETEK Drexelbrook has installed more than 25,000 ultrasonic sensors over the past decade, and its USonic-R level transmitter is a perfect choice for storm water measurement.

USonic-R is FM and ATEX approved. It has a patented SmartGain™ feature that eliminates the issue of false echoes. SmartGain™ quickly recognises pumping station obstructions, such as ladders and pipes in sewage wells, helping ensure accurate level readings.

USonic-R picks up data from two separate ultrasonic sensors placed at different locations. Data is logged, flow calculated from weirs or flumes, and signals can be sent to emergency pumps. The transmitter also can deliver crucial data, showing the state of sewage wells, basins, drilling mud and fluid in tanks.

USonic-R incorporates a converter and a datalogger. Data is delivered either as a 4-20mA or Modbus signal, which allows for easy integration into the most common SCADA systems. The instrument works seamlessly with RTUs, simple pump controls or PLCs. This is important for remote installations in which intelligent or autonomously operation is required for level measurement, flow calculation, or pump activation when necessary.

The versatile USonic-R even allows two individual ultrasonic sensors to be connected, enabling users to calculate the sum or differential of pumped volume by measuring each side of two basin walls. The unit is weather proof, IP66/NEMA6-P rated, and UV protected, meaning that, in general, the device requires no additional protection.