GPR, ARCSWAT AND SUAV TO ESTIMATES SEDIMENTS ACCUMULATION AND WATER VOLUME WITHIN KELLER RESERVOIR, UNION COUNTY, PA

Keller Reservoir located 8.7 miles East of Lock Haven, PA, serves as a source of drinking water supply for 19,500 subscribers. The reservoir is fed by McElhattan Creek and East Kammerdiner Creek. These creeks carry a substantial amount of sediment with surface run-off during high precipitation events. Over 90% of the watershed is wooded with deciduous forest and 7% agricultural land. Accumulation of sediment poses a major problem because it reduces the potential of water storage within the dam and raises cost of filtration at water filtration plants. To evaluate the volume of the sediment in Keller Reservoir, three techniques including: 1) Ground Penetrating Radar (GPR) surveys 2) Application of ArcSWAT and 3) a small Unmanned Aerial (sUAV) Vehicle for photogrammetry to identify the accurate topographic of the dam boundaries. GPR data shows high sediment accumulation near the dam and the 3D bathymetry and sub-bathymetry models revealed the total volume of sediment that has accumulated since the construction of the dam. The 3D model has also revealed the volume of water within the reservoir at present. The water volume was estimated to be 247,474.15 m³ and the sediment deposition of 311,359.27 m³. This showed that the Keller Reservoir has lost over 50% of its storage capacity since inception.