Hard Hat News, 2006. Demolition of the Carbonton Dam, by Gwen Laird Pernie
In the Central Piedmont Region of North Carolina an effort is underway to restore 10-miles of the Deep River, a tributary to the Cape Fear River Basin. The river has been environmentally damaged for the past 200 years, when the first dam was built at Carbonton to power a mill on the riverbank. This $8.2 million dam-removal project, the largest ever of its kind in North Carolina, is also the first dam removal in the state to be done primarily for mitigation purposes. This project is the culmination of a five-year planning effort by Restoration Systems, LLC, of Raleigh, NC (owner of the dam) to re-establish the native aquatic ecology of the Cape Fear River Basin to gain “mitigation credits” under the North Carolina Ecosystem Enhancement Program. It was planned and is being implemented in close coordination with multiple county, state, and federal regulatory agencies. The dam is a former hydropower generating facility that is licensed under the Federal Regulatory Energy Commission. Site contractor for the project is Backwater Environmental of Pittsboro, NC, a subsidiary of Osborne Company General Contractors of Eden, NC. Osborne will handle the physical demolition and heavy work of the project, while Backwater will handle the earthmoving, grading, site restoration, and softer work. Restoration Systems retained Milone & MacBroom Inc. (MMI), of Cheshire, Connecticut and Greenville, South Carolina to investigate the existing dam and assist with agency permitting, and to design the removal strategy, prepare construction documents, and handle inspection during demolition. MMI is also designing a future public recreation park that will occupy the south riverbank at the dam site. According to Ken Kloeber, branch office manager of MMI’s southeastern regional office in Greenville, the most challenging aspect of the project was to design a dam removal sequence and methodology that will get heavy equipment in and out of the river quickly. “The challenge is to minimize the exposure of the removal operations on the Deep River system and the aquatic critters that this entire project will benefit,” Kloeber explained. “We wanted to avoid short term effects while accomplishing the greater good in the long term.” “An additional challenge was that much of the planning involved working with and getting approval from many county, state, and federal agencies–sometimes with overlapping authorities–on a fast-track schedule,” Kloeber continued. “Hydropower dam demolitions involving FERC approval typically take years in the planning and design stage. With the owner, contractor, and agencies cooperating, this one took a matter of months.” “Every dam removal is unique because no two are constructed the same,” Kloeber said. “We had to first evaluate and understand the structural components of the spillway and the powerhouse before designing the demolition methodology and sequence. It’s typically easiest to demolish dams in reverse order of their construction sequence.” “The planning of the particular project has been especially interesting because we were able to locate original 1921 construction photos of the powerhouse and spillway in their de-watered state, which gave us insight into how the facility was constructed,” Kloeber stated. “It literally painted a picture of what was hidden under the water, and allowed us to anticipate in order to save time.” “Typically, dam removals involve starts and stops as structures are uncovered and new situations need to be assessed, Kloeber said. “Having the right information and evaluations of the structures up front has allowed this demolition to proceed very smoothly. To the credit of Restoration Systems, the owners recognized the need for adequate investigations right away, and they provided us the resources to make that happen.” “Because of its age and type of construction, the Carbonton Dam is eligible for the National Register of Historic Places,” stated Kloeber. “So, Restoration Systems has taken extra care to preserve the history of the structures.”
Here’s a short music video I made following a preliminary reconnaissance trip on the Deep River hosted by Restoration Systems for the NC Division of Water Quality. Three years later, in 2006, we removed the Carbonton Dam in order to restore the area through which we are traveling from impoundment to natural river. The lowered impoundment revealed rapids and channel features not seen since the early 1800s. The newly restored river has subsequently thrived, including the re-establishment of the federal listed Threatened and Endangered Cape Fear Shiner, which was reported nationwide.
New faculty members at the University of North Carolina at Chapel Hill spent the week after Commencement on the Road, getting to know the state and its people a little better. May 12th – 16th marked the 11th Annual Tar Heel Bus Tour. The idea of the bus tour is a way to teach new faculty about NC, its needs and where most of Carolina’s undergraduates grow up. This year the Institute of the Environment department at UNC was able to choose a site to visit. They chose RS’ Carbonton Dam project site.
Present day Carbonton.
The bus arriving at Carbonton Dam Park.
George Howard addressing the group
Dickie Harrison of Deep River Parks Association (keeper of the Carbonton Dam Park), Uncle Larry and Barrett Jenkins.
Adam Riggsbee addressing the group.
This morning George Howard and I drove down to the site of the former Carbonton Dam to meet Randy Turner and Dr. Adam Riggsbee, both of Restoration Systems, and Dick Harrison, Executive Director of the Deep River Parks Association.
Adam, Randy, Dick & George assemble in front of the old powerhouse.
Carbonton Dam was removed almost a year ago, but the project is nowhere near finished. As anticipated, Restoration Systems is working hand-in-hand with Mr. Harrison to plan and implement a public park at the site, which is the exact geographic center of the state of North Carolina resting in Chatham, Lee and Moore Counties.
On our visit today, we had a chance to take a look at the transformation that the park has undergone in the past year. We were all amazed, in hindsight, to look at the flowing river and the massive remnants of the dam along the bank of the river. It is a little piece of history that will remain intact in the community, along with the steep powerhouse that remains on the opposite bank of the river. It is a testament as to how much progress can be made in one year.
This photo shows the piece of the old dam that remains, along with the newly sprouting grass along the bank.
Our resident park expert, and “office blog laureate,” Randy Turner, spent a great deal of time on the planning and implementation of the layout and design of this green space; and it shows. Some trees needed to be removed to make space for the park, but Randy hand-picked several immense, aged trees to shade the area. It was truly fascinating, and rather humbling, to stand next to these century old trees that have stood the test of time. It reminds you of where you stand in the scheme of things.
A view of some of the trees lining the park.
We all walked from the car and descended down a winding gravel pathway toward the river bank, which was a beautiful sight, given the time of year and the vivid colors of the leaves. Randy explained that a system of tubing and mats, about three inches deep, was placed below the surface of the gravel to provide stability and to keep the gravel from shifting off of the pathway. It was a very innovative and thoughtful solution to a possible erosion problem in the future.
A view of the gravel path leading to the future boat ramp.
Standing on the bottom of the path near the bank, I was reminded of the thick brush and overgrown weeds that shadowed the view of the river less than a year ago. Now the area adjacent to the powerhouse is lined with an expansive grassy field leading to the river.
The bottom of the park, which used to be overgrown with thick brush.
It was a pleasure getting the chance to meet Dick Harrison and gather an idea of his plans for improving the park and the community by keeping this historical area alive. He seems to take a great deal of pride in planning the park and working with Randy to get it right. He summed it up best when he was standing on the lawn alongside the river. “Can’t you just picture it?” he said. “I’ll be standing right here in this spot next summer cooking hamburgers on the grill.” We agreed that we were anticipating a Restoration Systems BBQ at the park in the spring. The site will also play host to the 9th annual canoe trip on the Deep River on New Year’s Day; an event that Mr. Harrison says he has participated in every year since its inception, along with many other members of the community.
Randy, Dick & George discuss plans for the park.
We all take great pride in the new park, resulting from a great deal of hard work, planning and community support. We look forward to keeping you updated on our progress, the renovation of the powerhouse as a public use facility and, of course, events that are certain to take place at the park in the near future.