Engineers pressed to avoid delay in dam construction
It appears engineering estimates were insufficient and the contractors building the Tired Creek Lake dam are within 30 days of running out of suitable soil to use in building the earthen dam for the 960-acre lake.
Grady County commissioners met in a special called meeting Tuesday afternoon to discuss the situation with representatives of Schnabel Engineering, who designed the dam and are being paid by the county to serve as the project managers, and Brad Cole Construction, which is the general contractor for the construction of the dam.
Ronnie Mauldin and Randy Robison of Brad Cole Construction told commissioners that unless more suitable dirt can be found within approximately 30 days work on the dam will come to a halt.
Chuck Wilson and Brad Boyer, who are the dam engineers with Schnabel who designed the dam and are managing the project for the county have identified a new potential borrow pit on the east side of the dam.
The issue with soils on the project has been going on for several weeks engineers say, but county officials just learned of the problem late last week.
The dam engineers told commissioners this week that results from lab tests on soil samples out of a Tallahassee laboratory caused the engineers to question the suitability of the soil going into a section of the dam where a concrete seal wall is to be constructed on the front side of the dam.
Schnabel sent samples to three other labs and the results were “significantly different,” according to Wilson.
Vice Chairman LaFaye Copeland asked the engineers how could the results be so different.
“That is a good question and we don’t know what happened. We’ve been checking with our folks to try to come up with an answer. We don’t have an answer yet,” Wilson said.
The dam engineer added, “We’ve been investigating this for a while and trying to wrap our hands around this thing.”
Schnabel has ceased using the Tallahassee lab for soil testing.
As a result of discussions between Schnabel and Brad Cole Construction, two contract change orders were presented to the county for approval late last week. One called for the addition of $91,213 to the contract with Brad Cole to cover the additional cost to mobilize to open a second borrow pit east of the dam. The second change order was for a credit for $214,783 if the county agreed to delete the wave protection wall and replace it with rip rap and 10 oz. fabric.
Wilson and Boyer told commissioners Tuesday that when the decision was made three years ago to build the sea wall the cost estimates for a rip rap option were significantly higher than what the actual cost would be.
“Most dams have rip rap so this is not anything unusual,” Wilson said.
Commissioner Billy Poitevint asked if a change to a rip rap wall would impact Brad Cole’s warranty on the dam and Brad Cole officials indicated it would not.
“We’re more comfortable with rip rap once we realized the soil problem,” Robison said.
Grady County Attorney Kevin Cauley reminded Wilson and Boyer that the county commission had made the decision to go with the concrete sea wall option because of the lower cost of maintenance versus rip rap, to allow for public access and fishing from the wall, and to give the dam a cleaner look. He also questioned why the option to remediate the issue had not been proposed.
“The first I heard of this issue was yesterday. Eliminating the concrete wall is just one option. Another option would be to remediate the problem and stay with the current design,” Cauley said.
Wilson projects about 4,000 yards of dirt suspected of being unsuitable would have to be dug out of the dam and replaced. The engineers are concerned that unless the dirt is replaced the sea wall could eventually crack or fail, according to Wilson.
“In 2011 you qualified the borrow pit was suitable and sufficient for the needs of this project. We relied on that, Brad Cole relied on that and the Corps relied on that so Schnabel should absorb 100 percent of the cost of opening another borrow pit. I assume if the county chooses to remediate and stick with the concrete wall there will be no savings, but also there will be no additional cost to the county. This is not an error of Grady County. It is a result of testing done by your firm,” Cauley said.
Commissioner Charles Norton piggybacked on Cauley’s comments and said, “Schnabel Engineering is the project manager and you test all dirt. Your test facility is a subcontractor of yours and not the county. It seems you are asking us to absorb this additional cost for mobilization and this is not our responsibility. Brad Cole bid on the dam based on the borrow pit you said was available. It’s not their responsibility for the additional mobilization costs.”
Cauley also questioned Wilson and Boyer on the size of the borrow pit needed to complete the dam. “These estimates are based on 10 acres, but I’ve heard anything from 15 to 20 acres,” Cauley said.
“We would not open anything not necessary. Until we do test pits we don’t know,” Boyer said.
The dam engineers said that regardless of whether the county elects to stay with the current contract for a concrete sea wall or not an additional source of suitable soils must be found to finish the project.
Wilson said that he and Boyer would be taking samples this week and would have the results back in 14 to 17 days.
Cauley told the engineers that the county would do whatever necessary to keep the project on schedule and he requested that he be kept informed when issues such as these arise.
“Just keep me in the loop. This isn’t just as simple as approving a couple of change orders,” Cauley said.
Chairman T.D David backed up Cauley and instructed the representatives with Schnabel and Brad Cole to make contact with the county attorney regarding issues with the lake project. “Make sure everything starts with him and we can go from there,” David said.
Cauley advised the board that no formal action was needed on Tuesday, but Wilson requested the board give direction on the sea wall versus using rip rap.
“If there is no additional cost to the county on opening the borrow pit or the remediation to keep the concrete wall moving forward, we would want to stay with the concrete. If there is any cost to the county then we would need to come back and get action,” Cauley said.
“There is no additional cost if we stay with the concrete wall, all you are doing is showing us some savings if we went with rip rap, right?” Commissioner Poitevint asked.
“That’s right,” Wilson responded.
“Let’s all be clear it’s up to Schnabel to keep the project moving forward. It’s not the county holding anything up,” Cauley told the Brad Cole officials.
He added, “The posture we’re leaving in is that Schnabel is driving the boat on this.”
Brad Cole officials told county commissioners approximately 160,000 yards of additional soil is needed to complete the dam. They estimate that there are 30,000 yards left in the existing borrow pit.
The next progress meeting on the dam is scheduled for Tuesday, Sept. 16, but county officials said a called meeting would be scheduled sooner, if necessary.