A Garver-led project that helped a wastewater treatment
plant adhere to reduced permit limits has earned the Grand Award from the
American Council of Engineering Companies of Alabama. The Helena Wastewater
Treatment Plant Design Improvements project earned the award from the American
Council of Engineering Companies of Alabama’s Engineering Excellence Awards
contest.
The project consisted of multiple improvements that helped the Helena WWTP meet strict effluent discharge
limits for total phosphorus. Because it discharges into Buck Creek, reliable performance
and operation of the Helena WWTP is essential to maintain the quality of this body of water frequently used by the citizens of Helena and surrounding
communities for swimming, wading, canoeing, and fishing.
“The frequent-use of Buck Creek as a recreational
destination requires the effluent coming out of this plant to
meet stringent, near-reuse requirements,” said Garver Water Team Leader Brian
Shannon. “The improvements being made to this plant will uphold the health and
diversity of the natural species that inhabit Alabama’s most ecologically
diverse river system.”
To help the plant meet the current and future total
phosphorous requirements (0.20 mg/L and 0.043 mg/L), Garver first developed a
facilities plan that included a plant-wide evaluation of existing treatment
processes to identify shortcomings that hinder plant performance. That plan led
to phased improvements designed to meet current and future requirements.
Phase 1 of the project, which was completed in September
2017, included rehabilitation of the existing
secondary clarifiers, new tertiary filtration equipment, new chemical storage
and feed facilities, and a new UV disinfection process. Because the existing
plant hydraulics were limited, the design team had to develop a unique
disinfection and post-aeration strategy consisting of closed-vessel,
low-pressure UV disinfection followed by a low-profile, cascade aeration system
to provide treatment regardless of downstream water level conditions in Buck
Creek.
This is the second Grand Award earned by a Garver-led
project in the ACEC-Alabama contest. The Tuscumbia Water Treatment Plant and
Supply Improvements project earned the Grand Conceptor Award in 2013. That project was the first in the state
to use a blended series membrane process after Garver provided project design,
funding assistance, bond issue assistance, construction management, and
operation support in replacing a 60-year-old plant. The ACEC-Alabama Grand
Conceptor Award for 2018 will be announced at the awards presentation in April.