About Lake Conestee Dam Restoration project
We completed the Lake Conestee Dam Restoration Project in October 2025. The purpose of the LCDRP was to ensure that the vast store of contaminated materials behind the historic Lake Conestee Dam built in 1892 would not be mobilized downstream if the historic dam failed. The goal of this page is to give a bit of context, and at the very bottom, to provide fact sheets for more in-depth information.
Located approximately seven miles downstream from Greenville, South Carolina, Lake Conestee and the Lake Conestee Preserve provide unique and valuable ecological resources for the upstate of South Carolina through their riverine and lacustrine habitats and the associated upland resources. The lake was formed in 1892 by a dam across the Reedy River installed to provide hydroelectric power for Conestee Village and Conestee Mill. Built to last only fifty years or so, the dam was well beyond its engineered life span. As a result, it had significant deficiencies that required immediate action. If the dam were to have failed, there would have be serious consequences downstream, including the release of 2 to 3.25 million cubic yards of sediment contaminated with hazardous substances into the mainstem of the Reedy River, which flows directly to Lake Greenwood, Greenwood County's only source of drinking water. To put it into context, that is enough contaminated sediment to fill a football stadium to the brim twice over! A breached dam would also result in the loss of approximately 400 acres of riverine, lacustrine, and wetland resources in the reservoir and its upstream habitat, including a bird sanctuary providing a home to more than 225 species of birds. Finally, it would cost hundreds of millions or billions of dollars to clean up, decimate water-based activities and tourism on the Reedy River and in Lake Greenwood, and negatively impact property values all along the Reedy River system and Lake Greenwood.
Fortunately, there was a solution. Since 2012, three commissioned engineering studies and countless hours of work have pointed to the solution: construction of a new dam immediately downstream of the existing dam. Attempting to fix the existing dam or tear it out would result in mobilization and release of the contaminated sediments, a result DHEC and EPA have said is an unacceptable risk to human health and the environment. The Lake Conestee Dam Restoration Project (“LCDRP”) has consolidated the years of accumulated knowledge and effort and channeled it towards implementing this solution. With enormous support of the public in and around Lake Conestee and the Reedy River downstream of the lake, all the way to Lake Murray, and generous funding from the SC General Assembly, we will succeed. Now is the time to fix this for the communities of the Reedy River and for all South Carolinians. Now is the time.
Frequently Asked Questions
What is the Lake Conestee Dam Restoration Project?
The Lake Conestee Dam Restoration Project ("LCDRP") came into being to address the dangerous condition of the existing dam across the main stem of the Reedy River. The historic dam was built in 1892 to provide hydroelectric power for Conestee Village and Conestee Mill. Built to last only fifty years or so, the dam was well beyond its engineered life span. As a result, it had significant deficiencies that required immediate action. If the dam were to fail, there would be serious consequences downstream, including the release of 2 to 3.25 million cubic yards of sediment contaminated with hazardous substances into the Reedy River, which flows directly to Lake Greenwood, Greenwood County's only source of drinking water. A breached dam would also result in serious harm to the Conestee Nature Preserve and the loss of approximately 400 acres of riverine, lacustrine, and wetland resources in the reservoir and its upstream habitat. Finally, it would cost hundreds of millions or billions of dollars to clean up, decimate water-based activities and tourism on the Reedy River and in Lake Greenwood, and negatively impact property values all along the Reedy River system and Lake Greenwood. The LCDRP aimed to prevent this tragic outcome by constructing a new dam immediately downstream of the existing dam, thereby holding the hazardous substances in place, capped in place and undisturbed.
What is the Lake Conestee Nature Preserve?
Conestee Nature Preserve is a 400-acre (160 ha) preserve along three miles of the Reedy River in Conestee, South Carolina, just 7 miles downstream of downtown Greenville, with 13 miles (20.9 km) of trails, more than 6 miles (9.7 km) of them paved and 1 mile (1.6 km) of boardwalk. The Preserve contains both hardwood and evergreen forest, extensive wetlands, and a rich diversity of reptiles, mammals, and birds. At least 223 bird species have been reported, and the National Audubon Society has designated the park as an Important Bird Area of Global Significance. In 2016 the state of South Carolina made the privately owned facility a wildlife sanctuary. It is truly a treasure. Take the time to walk the trails with your family or friends. You will not be disappointed!
What is in Lake Conestee?
Below the surface of this ecological treasure, Lake Conestee hides a terrible secret. Since the early 1800s, the area now known as Lake Conestee served as a collection point for a large portion of Greenville County's economic growth. It is estimated that the lake contains between 2.5 and 3.25 million cubic yards of sediment -- enough to fill a football stadium 1.5 or 2 times over. Unfortunately, the vast majority of the deeper sediment is contaminated with hazardous substances, including toxic metals like chromium and mercury, PCBs, polycyclic aromatic hydrocarbons (PAHs), pesticides, and others. Many of these contaminants do not break down quickly and are carcinogenic, and most are present in the deeper sediments at levels well above human health and ecological limits. Fortunately, the sediments deposited since the Clean Water Act's creation if 1972 have been much cleaner, but they cannot remove the legacy of Greenville's history.
What would have happended to that sediment if the dam had failed?
The sediment and the hazardous substances contained in the sediment would have been eroded by the flow of the river and by rainfall, and would thereby be mobilized downstream. These contaminants would move down river for years, ending up in Boyd Mill Pond and Lake Greenwood. Large storms and rain events, like those commonly experienced during the wet season and with hurricanes, would move the pollutants faster.
What would the impacts be to human health and the environment?
The impacts would have been severe. The persistent nature of many of the hazardous substances means they would not readily break down. They would have been present in the river and the lake for years, negatively affecting human health and the natural ecological systems of the river and the lakes. Many become concentrated in the food chain, compounding their effects over time and potentially making fish unsafe for human consumption. Some believe the sediment also contains large amounts of nitrogen and phosphorus; if true, this could lead to algae blooms and fish kills.
Would there have been flooding or flood damage?
Yes, but there likely would not have been a huge wave of floodwaters. Rather, some of the mill buildings adjacent to the river would be flooded, and the bridge at Conestee Road over the Reedy would be in the direct path of flood waters, debris, and a large mudflow.
How expensive would cleanup be?
Estimates vary, ranging from the hundreds of millions to billions. Also, Lake Greenwood is the sole source of drinking water for the area. This type of contamination would likely require major retooling of the water treatment process serving the community, costing millions more.
What was the solution to this problem?
Since 2012, three commissioned engineering studies and countless hours of work have pointed to the best solution: construction of a new waste containment structure (i.e., a new dam based roughly on Klienschmidt's Recommended Alternative #6) approximately feet (50') downstream of the existing dam and built to last into the next century. Attempting to fix the existing dam or tear it out would have resulted in mobilization and release of the contaminated sediments, a result DHEC and EPA have said is an unacceptable risk to human health and the environment. The construction phase included safeguards to protect against contingencies during construction.
