Investigation of seepage near the interface between an embankment dam and a concrete structure: monitoring and modelling of seasonal temperature trends

Seasonal subsurface temperature monitoring, which exploits the fact that increased seepage flow may locally alter distribution, is a useful approach for leakage monitoring and evaluation within embankment dams their foundations. At Mactaquac Generating Station, New Brunswick, Canada, spatial temporal variations of have been monitored modelled at steeply inclined interface between compacted clay till core dam an abutting concrete diversion sluiceway. Over 4-year period, two seasonally recurring anomalies different depths were observed by fibre optic distributed sensing in structure close to interface. A 3D coupled heat transport model was developed FEFLOW simulate distribution resulting from seasonal air reservoir temperature. Leakage zones near simulated embankment. depth 13 m below crest, significant lag time shows responsible anomaly must be limited enhanced concrete. much shallower depths, where temperatures fluctuate nearly phase, paths are more challenging determine.