Engineers submerged a 1,100-foot, 42-inch force main across the bank of Lake Langhofer on Monday as part of a yearlong project for Pine Bluff Wastewater Utility.
The sink completed the first of two phases of a $10.58 million project to replace the existing force main that has been in service since the mid-1960s, according to utility General Manager Ken Johnson.
A force main moves wastewater to a treatment facility, and the project is the largest civil engineering venture in which PBWU has been involved since 1984 or earlier, according to Johnson.
“We made improvements with the new line,” Johnson said, adding such pipelines usually sever and need to be replaced after about 60 years. “The next stage is to replace the old antiquated pumps on Kansas Street. Pumps will be upgraded with more efficient pumping equipment.”
Independent reporting for Pine Bluff & Jefferson County since 1879.
Johnson said the existing line has sustained breaks on land rather than underwater, allowing engineers to make fixes.
The city of Pine Bluff provided $5.5 million from American Rescue Plan Act funding for the project. The design state began in March 2020, but the notice to proceed was not given until Feb. 5 of this year.
“We appreciate the collaboration with the city of Pine Bluff, the Community and Economic Development through ARPA funds and through wastewater coffers as well,” Johnson said. “We were able to do this project without a rate increase, and hats off to all the parties involved in this particular project. We were anxious to get it off the radar screen and get everything to action. It was long overdue.”
Crist Engineers designed the force main with Garney Companies Inc. as the contracting firm.
The total cost for the first phase was $6.04 million. The second phase will cover 2,100 linear feet of 42-inch PVC pipe and 50 linear feet of 36-inch PVC pipe, and is estimated to be completed by Feb. 7, 2025.
“This one is costly because it’s a 42-inch force main that has to go across a water body,” Johnson said.
Cranes on the lake just off the Arkansas River were used to float the force main to the shore where the PBWU Kansas Street station is located. The main was then sunk in a controlled manner.
“We have mats already underwater and we have a good aggregate base for the foundation it will be placed on,” said Craig Johnson, vice president of Crist Engineers. “We’ll know exactly where the force main will be placed at all times.”
The engineers have at least another month of work to do at Lake Langhofer, Craig Johnson said, including backfilling rock, putting protective mats on top of it and installing tie-ins on both sides of the force main.
PBWU is completing a service evaluation for improvements to its entire system. Ken Johnson estimated about $28 million will be needed over the next 10 years.
“We know these improvements have to be made,” Ken Johnson said. “In order to make those improvements over the next 10 years, we’ll have to go back and reevaluate our current revenues. It’s going to be a process.”
From left: David Poe, technical services advisor for Pine Bluff Wastewater Utility; Craig Johnson, vice president of Crist Engineers; and Ken Johnson, PBWU general manager, observe the float-and-sink operation of the new force main at Lake Langhofer on Monday, Sept. 9, 2024. (Pine Bluff Commercial/I.C. Murrell)