ROV PENETRATION INSPECTIONS
Farr Pump Plant, Willow Creek Intake and Grandby Lake Intake
Project completed August 2014
Farr plant intake inspection: Required the internal and external inspection of the intake structure utilizing a SEAEYE Falcon ROV. The structure was located in 113 feet of water at an altitude of 8200 feet. A wet diver team was utilized to remove a 48 inch diameter access hatch to allow entry into the intake structure. In conjunction with the ROV inspection, an 8000 pound dewatering bulkhead was placed and removed in 3 separate positions to allow the three six foot diameter intake tunnels to be dewatered.
Willow Creek Intake inspection: The Willow Creek intake is located in approximately 40 feet of water at an altitude of 8200 feet. An internal and external inspection of the intake trash rack structure was performed. The 120 foot vertical drop shaft and the 300 foot horizontal 6 foot diameter concrete intake pipe were inspected. At the end of the pipe, the closed guardian gate was inspected. A wet diver was utilized to remove a trash rack to provide access for a Seaeye Falcon ROV to perform the required inspections.
Grand Lake Intake Inspection: The Grand Lake intake is located in approximately 80 feet of water at an altitude of 8200 feet. An internal and external inspection of the intake trash rack structure, the 120 foot vertical drop shaft, and the 350 foot horizontal six foot diameter horizontal pipe, reducing down to 24 inch for the last 25 feet were inspected.
The twin guardian gates at the end of the line were inspected. A wet diver removed the trash rack for the ROV access. A Seaeye Falcon was utilized to perform the majority of the inspection in the larger diameter pipe. A Seabotic LBV 200 was utilized to perform the 24 inch diameter pipe and guardian gate condition inspection.