By MC3 Emiline Senn, NPASE West
SW1 Honer Villanueva, NMCB 3, cuts rebar beams with an oxygen acetylene torch next to a Caterpillar 390b during a seaplane ramp construction project, San Diego, Calif., Feb. 3. Seaplanes had heavy use around Coronado, Calif., during World War II. (Photo by MC2 Mark El-Rayes/150203-N-TQ272-061)
Seabees assigned to Underwater Construction Team (UCT) 2 completed the conversion of an old seaplane ramp to create a boat ramp at Naval Air Station North Island (NASNI), Coronado, Calif., May 27.
The seaplane ramp, dating back to World War II, had been in use by various expeditionary and special operations units in Coronado, but was unable to safely handle the weight of the Navy’s newest boats. There were no original plans or drawings for the seaplane ramp, according to Chief Builder Jason Cortez, project officer in charge, UCT 2.
The Navy began researching a replacement for the ramp. The cost for a contractor was estimated at $2.6 million, according to Dave Watts, facilities manager, Navy Expeditionary Combat Command Pacific. UCT 2 was able to work with NASNI to reduce the cost by more than half.
During the initial phase of the project, the Seabees determined the majority of the old seaplane ramp was not structurally sound. This made the original renovation plan untenable, and forced the engineering design firm back to the drawing board. The new design added significantly more work to the project, but the Seabees pressed on.Seabees assigned to NMCB 3 and UCT 2 reconstruct a historic seaplane ramp formerly used during World War II, NAS North Island, Coronado, Calif., March 18. Photo by MC2 Carlos M. Vazquez II/150318-N-WD757-038)
“We ripped out about 240 cubic yards of concrete, and placed or poured 300 cubic yards,” said Cortez. “It’s a significant project for us. We laid an estimated 16,000 feet of steel and added a floating dock.”
This is the only boat ramp on NASNI and will be used for riverine craft, special boat teams and port operations among other uses.
“This ramp was designed for daily port operations and special watercraft,” said Cortez. “We specifically designed it for the Mark V and new Mark VI patrol boats. A Mark VI boat, fully loaded with the truck and trailer will weigh upwards of 110,000 pounds. We built the ramp at an angle that will hold that weight.”
UCT 2 Seabees used part of the old ramp and interwove the original foundation with the new design, increasing the overall load capacity.
“We used mechanical couplers to join the old piles to the new piles,” said Builder 2nd Class (SCW/DV) Chris Farmer, UCT 2. “Anti-corrosive inhibitors were mixed into the concrete so it will last longer than the previous ramp.”
Overall, the project took less than a year to complete.
“Construction took four and a half months [of] actively swinging a hammer,” said Cortez. “But we’ve been at it closer to eight months, including site visits and the project package that was put together.”
The boat ramp was completed in conjunction with Seabees from Naval Mobile Construction Battalion (NMCB) 3, NMCB 4 and Construction Battalion Maintenance Unit (CBMU) 303.
Navy UCTs provide a capability for construction, inspection, repair and maintenance of ocean facilities in support of Navy and Marine Corps operations, including battle damage repair. Teams also maintain a capability to support a Fleet Marine Force amphibious assault, combat service support ashore, and self-defense for their camp and facilities under construction, as well as emergency and disaster response and recovery operations.
BU2 Christopher Farmer, UCT 2, briefs NAVFAC Commander Rear Adm. Kate Gregory on the construction of a boat ramp at NAS North Island, Coronado, Calif., May 19. (Photo by BUC Jason Cortez/150519-N-ZZ999-001)