Central Arkansas Water officials pick route for new large-diameter water main from Lake Maumelle

Central Arkansas Water officials have settled on a proposed route for a new large-diameter water line that will run from Lake Maumelle to one of the utility’s treatment plants.

Officials have been preparing to build the new line for years. The project was one of three major endeavors cited by utility officials when they decided to enact a 10-year schedule of customer rate increases around 3½ years ago.

Staff worked with the engineering firm Garver last year to review four potential routes from the reservoir to the Jack H. Wilson Water Treatment Plant in west Little Rock.

Elizabeth Heiles, a senior engineer with Central Arkansas Water, told the utility’s board of commissioners Thursday that officials considered economic, social, environmental and operational factors when evaluating the routes.

Depending on the path of the new line, crews might have to bore under a highway, excavate rock or build aerial crossings, all of which would increase the cost associated with the project, she said.

On the social impact, officials considered the businesses and homes that might be impacted as well as the number of easements that would need to be obtained, Heiles said.

Currently, there are two raw-water lines that connect Lake Maumelle to the Wilson plant: a 48-inch-diameter line constructed in 1957 and a 72-inch-diameter line constructed in 1978.

The route selected by Central Arkansas Water would have a new 72-inch-diameter line run parallel with the other two existing water lines until they reach the area of the Little Maumelle River. At that point, the new line would diverge to run parallel with existing overhead electric transmission cables, according to Heiles.

“This is not completely set in stone,” she told board members. “As you know, when you get into a design there will be things that will alter this.”

The larger of the two existing lines was inspected in 2024, and sections of it were repaired earlier this year, Heiles said. The line is in good condition and crews will continue to make repairs over the coming years, she said.

Concrete pipe has a useful life of anywhere from 50 to 100 years, she said, noting that the smaller line is more than 70 years old and the larger line is 48 years old.

“So we’re starting to get to that point where we really are planning for the future for the redundancy and resiliency of this pipeline,” Heiles said.

As for the size of the new line, officials initially were considering a 60-inch-diameter line, but upon a review of the cost and hydraulics, the recommendation was to pursue a 72-inch-diameter line. This meant the utility would have “a fully redundant line to our existing one,” Heiles explained.

Tearing out the existing 48-inch-diameter line and replacing it with a new 72-inch-diameter line was a possibility with one of the proposed routes. Instead, based on the selected route, Central Arkansas Water plans to leave the smaller line in place and continue using it as long as it is feasible to maintain it, commissioners were told.

It is expected to be years before the new line is installed underground. If design work begins this year, construction might begin in 2029 and last until 2032, Heiles said.

Thursday’s presentation was an information-only item. The utility’s board is expected to take up an engineering and design contract tied to the project within the next month.

In addition to Lake Maumelle, the utility has another source-water reservoir, Lake Winona, which feeds the Ozark Point Water Treatment Plant at Little Rock’s Knoop Park.

When utility officials requested the 10-year schedule of rate increases, part of their rationale was to fund three major projects: construction of the new Lake Maumelle line, remediation of an invasive aquatic plant in the lake and an overhaul of the Wilson plant.

The rate schedule, which the board adopted in January 2023, will raise rates for customers every year through 2032. The typical residential customer’s monthly bill is expected to double by the end of the 10-year period compared with 2022 rates.

The board also elected a new slate of officers for the 12-month period that runs through mid-2027 during Thursday’s meeting: Kevin Newton is replacing Kandi Hughes, the outgoing chair; Jay Hartman is replacing Newton as vice chair; and Melanie Hoggard is replacing Hartman as secretary/treasurer.

The slate was approved in a unanimous voice vote of the seven-member board, with two commissioners absent. The officers’ terms will begin July 1.

Newton, one of three North Little Rock members of the board, is the president of C.B.M. Construction Co. He previously served as chair from 2022 to 2023.