Movement of the landslide at the Ituango Hyroelectric project in Colombia is reported to have exceeded an alarm threshold of 10mm per hour resulting in the evacuation of workers at the site.
Project developer Empresas Públicas de Medellín (EPM) has said in a statement at the risk of failure at the dam is high with concerns over the stability of the dam due to issues with the abutments, as well as concerns over stability of slopes above the impounded reservoir.
EPM has said that the water level impounded by the dam is currently at 393m and, with current rainfall levels, the company estimates that the level will overtop the 401m high dam in mid-June. EPM has said that the spillway will be used to release the water.
Ground monitoring of the slopes above the reservoir and the dam is continuing.
EPM’s main concern currently is seepage within the dam and bentonite grouting work was being undertaken to improve the permeability of the dam and prevent loss of fines.
The grouting work and efforts to raise the dame to its full 410m height are believed to have been suspended following the increased rate of ground movement.