HINTON, W.Va. -- It took five years and a little less than $30 million to complete the Bluestone Dam 60 years ago.
Now, an upgrade program under way for the past 10 years has pumped another $130 million more into the flood-control structure, and it might take another decade and an additional $200 million or more to complete improvements to the dam to make sure that, even in the event of the most severe storm imaginable, the structure -- which has never budged from its bedrock foundation -- never will.
The dam provides protection from flooding for Charleston and the rest of the Kanawha Valley.
While the dam has not significantly changed over the years, design standards and threat assessments have, leading to Bluestone's massive 20-year makeover.
When the dam was being planned in the late 1930s, engineers designed it to be able to safely contain runoff from the region's worst storm on record, which at the time was a 1916 hurricane that dumped more than 13 inches of rain in 24 hours across much of the upper New River watershed.
In the 1990s, the U.S. Army Corps of Engineers instituted the Dam Safety Assurance Program to make sure dams built in the early to mid-1900s met modern design standards and would continue to operate safely long into the next century. The program followed the collapse of Idaho's Teton Dam in 1976 and the failure of the Kelly Barnes Dam in Georgia in 1979.
In conducting the review, the nearly 50 years of weather observations and flood data recorded since Bluestone Dam became operational were taken into account, along with new Probable Maximum Precipitation models developed by the National Weather Service. The 13-inch, 24-hour rain event used by the dam's designers in the 1930s was increased to a 20-inch downpour.
By factoring a 20-inch rainfall into the 4,565-square-mile watershed that drains into Bluestone Lake, Corps of Engineers planners determined, among other things, that the dam needed to be raised eight feet and anchors needed to be installed to better secure the dam's base to bedrock. New analyses made during the Dam Safety Assurance review of Bluestone also showed that the bedrock securing the dam might not be as strong as it was assumed to be in the 1930s, adding to the importance of extra anchors.
Additionally, penstocks designed to accommodate hydropower generation but, so far, never used for that purpose were determined to be in need of modification so they could be used to augment lake discharge during times of severe flooding.
A $19.1 million project to install concrete thrust blocks to support the dam, to modify penstocks to improve outflow, and build a temporary access bridge below the dam to accommodate construction got under way, and was completed in 2004.
Between 2004 and 2007, a $7.3 million project added a new concrete monolith to the dam's east abutment, and a new fishing pier to its west side. While that work was under way, Hurricane Katrina blasted across the Gulf Coast, causing a flood surge that led to the catastrophic collapse of the New Orleans levee system.
In the wake of that storm and levee failure, Corps of Engineers planners decided to take another look at worst-case scenarios involving flood-control projects across the nation.
The Dam Safety Assurance review and an Issue Evaluation Study that followed Katrina showed that, without additional improvements, "Bluestone does not meet current standards," according to Peggy Noel, a public information officer for the Corps of Engineers Huntington District.