By Stephanie Seymanski, PE and Rika Lashley, PE

Have you ever used a Slip ’n’ Slide? It can be great fun, just as long as it doesn’t empty out into a wastewater treatment lagoon! If you have nightmares of this nature, please read on.

Many smaller communities across the country rely on lagoon systems to treat their wastewater. Historically, lagoons were lined with clay liners and overlaid with riprap. Accessing the water surface of these lagoons was also relatively easy and safe.

However, over the past couple of decades, synthetic liners have replaced the older clay liners because they are more leak-proof and less susceptible to plant and animal activity which can deteriorate their ability to hold water. Many synthetic liners do not need to be covered and are exposed around the edge of the lagoon basin. Side slopes can also be as steep as a 3:1.