Robinson Lake

The Robinson Lake Dam was an unregulated, farm pond dam that posed multiple safety concerns as observed by CDM Smith in 2017. Located in Bartlett, TN, the dam is within the Carters Limestone Formation which is prone to solutioning and the development of karstic features. In 2019, the City of Franklin, Tennessee, proposed redeveloping the area into a new multi-recreational park around the lake. At the time, three sinkholes were present in the downstream area of the dam embankment, and water was visibly seeping under the auxiliary spillway through the right abutment.

S&ME’s Geophysical team completed a combination of Frequency Domain Electromagnetics (FDEM), Electrical Resistivity Tomography (ERT), and Spontaneous Potential (SP) surveys within the accessible portions of the site and overtop the lake to acquire additional subsurface information to assist CDM Smith’s evaluations related to seepage and possible karst risk.

The geophysical surveys indicated potential karst voids and fractured bedrock, some of which were not captured in test borings. Using these indicated geophysical anomalies, CDM Smith could target areas where those features could threaten the stability of the future rehabilitated dam if left untreated.