To measure flow rates at two influent channels at a wastewater treatment plant (WWTP) in Rzeszow, Poland, the Municipal Water and Sewage Company (MPWiK Sp. z o.o. w Rzeszowie) decided to install innovative non-contact laser technology. Teledyne ISCO LaserFlow® sensors were placed above the two channels and connected to a Signature® Flowmeter to resolve very challenging conditions without the need for expensive renovations of the channels to build flumes.