Road job cost put at $69 million

Work likely will begin before the end of the year on a long-planned project to improve a section of Cantrell Road in west Little Rock, a top official at the Arkansas Department of Transportation said Wednesday.

The section of Cantrell Road, which is also called Arkansas 10, crosses Interstate 430 between Pleasant Valley and Pleasant Ridge roads. With up to 54,000 vehicles traveling it daily, it is known as the busiest non-interstate road in the state.

Last week, Metroplan amended its transportation improvement plan, a list of all road work within the

central Arkansas region, to include a new estimated total cost for the Cantrell Road project: $69 million.

The plan previously used a $40 million estimate. But Casey Covington, deputy director for Metroplan, the long-range transportation planning agency for the region, said the original estimate was a planning estimate made well before a project design was developed.

The amount remains higher than even a refined estimate that state transportation officials used early last year. But the department had only picked Kiewit Infrastructure South as the contractor under a construction method the state is using for the first time but has been used with success in other states.

Called the construction manager/general contractor method, the Kiewit team has worked closely with agency officials to design the project in such a way that it will be completed in a timely manner while managing traffic throughout the work. Typically, the department designs a project and contractors submit bids based on their estimated costs of doing the work with the lowest bidder being awarded the contract.

Ben Browning, alternative-project delivery director for the department, said the latest figure remains an estimate, but the work with Kiewit has helped refine the cost.

“We’re at the point right now where we’ve been able to — with having that construction manager on board — get more accurate cost estimates,” he said. “The previous $40 million was just a planning estimate. It was set before we even knew what the interchange was going to look like or details of the design. There was very little detail on the improvements tied to that original estimate.”

Once the design is finalized, “we’ll be within 10[%] to 20% of that price,” Browning added.

That the project is a complicated one is no doubt. It is centered on a single-point urban interchange design in which the section of Cantrell, widened to six lanes from four, will use a ramp to carry traffic over the North Rodney Parham Road intersection rather than through it, as Cantrell does now.

The elevated roadway is similar to the ramp that carries traffic on Interstate 630 over South Shackleford Road in the Interstate 430/Interstate 630 interchange.

The “single point” in the interchange design would be underneath Cantrell at North Rodney Parham. One traffic signal would control traffic moving onto or off Cantrell, which would allow motorists going east and west on Cantrell to avoid stopping at a light to accommodate North Rodney Parham traffic, a feature that planners identified as a source of much of the congestion in the corridor.

The design also includes a feature known as a “Texas turnaround,” which will allow drivers traveling south on I-430 to turn east on Cantrell. Motorists actually would travel west for a short distance, then make what amounts to a U-turn back to the east underneath the Cantrell Road ramp.

The Texas turnaround would replace a loop ramp that traffic now uses to go from southbound I-430 to eastbound Cantrell and would eliminate an element that has the southbound I-430 traffic merging into the same lane used by eastbound Cantrell traffic to access northbound I-430.

A Texas turnaround on the west side of the interchange will allow some motorists exiting the Pleasant Ridge shopping center to go west on Cantrell as well as allow westbound motorists access to Trinity Assembly of God Church on the north side of Cantrell.

A traffic circle has been replaced with a new road that also would allow access to the church after residents in adjoining neighborhoods complained about the traffic circle and the potential to remove some residences.

A new road that would replace the traffic circle also would allow access to the church.

Another element of the construction manager/general contractor method involves arriving at the price and who will build it.

Kiewit isn’t guaranteed to win the job, but under the arrangement it will have the first opportunity to submit a bid, which Browning said he hopes will happen “in the next few weeks.”

That bid will be compared with independent cost estimators, including one that will develop a cost estimate to which neither the department nor Kiewit will have access.

Once Kiewit submits its bid, it will be compared with both cost estimates and must fall within 10%.

“When we determine whether to move forward or not, we can use some combination we think is most accurate,” Browning said. “Based on what the project really is, we can make that decision on which one or which combination we’ll use to compare the [Kiewit] price.”

If Kiewit’s bid is too high, the project will go through the regular bidding process. Kiewit also can participate in that.

The design also includes a feature known as a “Texas turnaround,” which will allow drivers traveling south on I-430 to turn east on Cantrell. Motorists actually would travel west for a short distance, then make what amounts to a U-turn back to the east underneath the Cantrell Road ramp.