Northern Kentucky Water District removed nearly 130,000 tons of sediment from two Fort Thomas reservoirs (Photo from NKWD)
The Northern Kentucky Water District recently completed a project to restore one of two reservoirs at its water treatment plant in Fort Thomas.
Two large reservoirs located at the site serve as water storage for normal operations as well as for possible emergencies that could disrupt pumping from the Ohio River. The goal of the project was to remove mud that had accumulated in one of the reservoirs over the last 55 years. The second reservoir is scheduled to be cleaned in 2023.
Originally built in 1889, the bottom of each reservoir is 50 feet at its deepest point and lined with cut sandstone blocks placed before modern machinery was available. There have been very few modifications to the reservoirs over the years.
NKWD employees stand beneath two excavators used during the project (Photo from NKWD)
Water is pumped from a building located along the river into the reservoirs before undergoing treatment, a process that over time allows some of the dirt naturally suspended in river water to settle to the bottom of the reservoirs. For nearly 80 years, the reservoirs were periodically drained, and the settled mud flushed into the adjacent creek. This practice was eventually stopped, which meant other methods had to be developed.
Over the past 30 years, the District used several different methods to remove mud without taking the reservoir out of service. Several types of dredges were used, but these methods were not able to stay ahead of the volume of mud brought in from the river.
The District determined that draining the reservoirs and using earth-moving equipment was the best way to clean the reservoirs. After meeting with contractors experienced in similar operations, the District decided to lead the project in-house and use staff to operate the excavators.
The District contracted with trucking companies to haul the mud to sites approved by the Kentucky Environment and Energy Cabinet to accept the material. Approximately 6,250 loads of mud were hauled away from the site in dump trucks — neaarly 130,000 tons.
“Each year, NKWD includes in its budget amounts for maintaining and enhancing its facilities”, said Joe Koester, Chair of NKWD’s Board of Commissioners. “We are very pleased to have completed this phase of the reservoir restoration project in-house, so that it will continue to provide our customers with safe, clean, reliable water at a reasonable cost for years to come.”
Northern Kentucky Water District
