Facultative Lagoon Design

Lagoon systems use natural and energy-efficient processes to provide low-cost wastewater treatment. Facultative Lagoons are one of the most cost effective wastewater treatment options for many small rural locations and communities as they have lower capital costs and are easier to operate and maintain than other systems.

A lagoon is a shallow body of water, usually contained in an earthen basin, designed to promote the biological treatment of wastewater. The biological process responsible for the removal of organic and suspended material requires wastewater to be retained in a lagoon for an extended period of time.

Site Selection

Facultative lagoons require a large area of land for construction. Barnes & Duncan will help you pick the best location for your lagoon considering land availability, connections to existing infrastructure and set back distances from residences.


We use the latest AutoDesk Civil 3D software to design solutions that are cost-effective for our clients. Using this technology we optimize the cut/fill material balance reducing the requirement to bring in outside material. Perimeter drainage and outfall ditches are also designed with ease.

Lagoon Liners & Controls

Depending on local clay availability we will recommend either a clay or synthetic liner. We are familiar with the latest design requirements for interconnection piping and lagoon degassing/dewatering systems. We are also acquainted with several options for leak detection.