A Levee/Embankment Failure and Quarry Flooding Attributed to the May 2010 Nashville Flood

During the May, 2010 Nashville flood, a 250 foot section of earthen levee and rock quarry wall located between Richland Creek and ReoStone Quarry failed, allowing the flood waters of Richland Creek and the Cumberland River to empty into, and fill, the ReoStone Quarry. As part of the forensic investigation team, K. S. Ware and Associates, L.L.C. (KSWA) was tasked by the Metropolitan Government of Nashville and Davidson County to evaluate and report on the site conditions, events and related issues that contributed to the failure of the levee and quarry wall.

After the flood waters receded and Richland Creek was routed away from the quarry, a large, linear, open joint, about 2 to 3 feet wide at its widest point, was exposed in the limestone bottom of the creek channel extending into the quarry. Observations of the site suggest that the open rock joints appear to have been formed by a rock stress release mechanism. Further evidence of this stress release was the presence of large limestone boulders at the bottom of the quarry that were observed below the location of the breach after the quarry was dewatered.

Large rock excavations, such as quarry excavations or highway rock-cuts, enhance the stress release mechanism along the remaining rock walls, allowing existing rock joints to increase in size, and thus increasing the potential of failure. There is strong evidence suggesting that water pressure in the rock joints from the flood waters produced sufficient hydrostatic pressure to move the wall of the quarry. A combination of events likely contributed to the wall failure including the flood waters, the site geology and the proximity of quarry operations. This presentation will discuss the flooding event and related issues contributing to this failure. 11 pp.