Preventing Backflow in the city of Zalec, Slovenia

Backflow, the undesirable reversal of the flow of water in a pipeline system, was a problem that was plaguing the City of Zalec in Slovenia. This was a long-term ordeal that presented itself along the Savinja River and prompted the city to take action towards a solution.

In the early 2013, the City of Zalec approached Nivo Eko, d.o.o. to help solve this problem. Nivo Eko is a well-recognised company known as the leader in flow barriers, head walls, drainage solutions and backflow prevention. The company’s engineering director, Marko Zibret, made it his mission to study and purchase a variety of backflow preventers, in particular, check valves.

After much time and money spent, he decided the best choice would be the duckbill style check valve due to its long life and maintenance free design. Once this decision was made, the next step was to purchase check check valves from various companies situated in North America as well as China.

Once these valves were purchased, the next step was to have these valves tested. Nivo Eko designed and manufactured a unique testing apparatus that allowed each valve to be tested under flow conditions, head pressures and continual back pressures.

After many hours of testing each check valve for both functionality and durability, it was decided the best design was the ProFlex® Duckbill Check Valve manufactured by Proco Products, Inc. in Stockton, CA. Since the start of this project, Proco has supplied Nivo Eko, d.o.o. with over 150 check valves ranging in size from 150mm (6”) to 1800mm (78”) that have been installed not only for the City of Zalec, but for other municipalities across Europe to combat the issues surrounding backflow.

www.procoproducts.com