Detection of internal defects in embankment dams

There are different types of hydropower dams of which embankment dams are the most common type. These dams might face internal erosion during their operational life and when the erosion develops the dam can break. In this project methods for erosion detection will be developed to mitigate this risk.

Internal erosion can be detected by leakage monitoring, although that can generally not pinpoint the location, and it is still often detected by visual inspection. In addition, there are limited opportunities to install sensors in or close to the core of existing dams. Hence there is a need to develop non‐destructive instrumentation techniques that have the capability of discovering the weak zones inside the core at an early stage. The overall goal is to develop improved monitoring techniques for early detection of internal erosion in embankment dams. The objective is to assess potential for long-term monitoring techniques in embankment dams, designed to detect defects inside the dam core, that are non‐destructive. The project will work with electrical resistivity tomography (ERT) monitoring data from two embankment dams, namely the Älvkarleby test dam and the dam upstream of the old power station in Näs.