LAN provided preliminary engineering, final design, bid preparation, and construction phase services for the expansion of the wastewater treatment plant from 5.0- to 10.0-mgd, including the influent lift station, primary clarifiers, aeration basins, secondary clarifiers, filters, UV disinfection and new administration building.

The existing lift station was designed for expansion. LAN evaluated the plant’s hydraulics under current and future flow conditions to confirm pump requirements. Pumping combinations were reviewed to confirm the proposed combination of pumps are capable of providing the flow and head under all flow conditions.

A new primary clarifier was designed to manage the increased plant flow. To address odor control concerns for the surrounding community, LAN designed a new primary clarifier with a cover which also incorporated positive ventilation. A berm was also constructed around the site to mitigate visual impacts of the plant and lighting.

LAN evaluated options for both biological and chemical phosphorous reduction. Chemical addition using ferric sulfate was recommended due to the simplicity of its inclusion into the current plant configuration.

A new dissolved oxygen control system, based on an open valve control strategy, was also included in the project. New controllers were added to the existing blowers to accommodate this upgrade. Additional process units included a new secondary clarifier, RAS/WAS pump station designed to accommodate the next two phases of expansion, two new dual media gravity sand filters, and additional UV disinfection modules.