By Dr. Michael Izard-CarrollMarch 31, 2018
Hurricane Maria made landfall in Puerto Rico in late Sept. 2017. While the majority of sustained news media coverage was concerned with power restoration, there were countless other blows to critical infrastructure resulting from the storm; the 90-year-old dam in Guajataca was one such structure.
On Sept. 22, dam operators notified authorities that a failure of the dam's spillway was posing a significant risk to the dam's structural integrity, which was putting some 70,000 residents in nearby communities at risk; a number of communities evacuated at the urging of Puerto Rico Gov. Ricardo Roselló, who had solicited assistance from local police and the Puerto Rico National Guard in the effort to get people out of harm's way.
The Puerto Rico Electric Power Authority, who owns the dam, received emergency assistance through the Federal Emergency Management Agency; FEMA in turn sought technical expertise from the U.S. Army Corps of Engineers for both performing inspections and actual repair work to the dam.
The USACE Jacksonville District was in charge of the dam inspection project and the district requested assistance from Buffalo to provide condition assessment and determine detailed measurements for repair design to the intake tower of the dam.
The USACE Buffalo District dive team heeded the call to action and mobilized to Isabella, PR to perform underwater assessments of the dam from Feb. 26 through 28, 2017, after several months of repairs and maintenance work were already underway following the storm on the emergency spillway at the dam. The inspection work the team performed was on the dam's tower, which was not related to the spillway concerns.
"We first used an ROV [remote-operated vehicle] to give us an idea of the safety conditions below the water, before we were willing to send a diver down there, as well as inspect and record portions of the structure that would not be accessible to one of our divers" said Weston Cross, a Buffalo District Engineer and dive team member. "We were able to determine that the gates were where they were supposed to be, the concrete was in good condition, and there weren't any obstructions that could foul the diver.
There were a total of six divers on the team, each from the Buffalo District, including Shanon Chader, PE Brian Dockstader, Michael Draganac, Andrew Hannes, David Bala, and Weston Cross, PG. Overall, the ROV inspection occurred over two days, followed by two days of dive inspections.
"We had to be self-sufficient," Cross said. "This mission was unique in that we had no electricity on the dam and there were some logistical challenges we had to overcome as this was our first time inspecting the structure; we had to familiarize ourselves with it."
While the Buffalo dive team's focus was exclusively to perform inspection work on this mission, the team has the capability of performing specific types of small repair work at sites they inspect.
The life of a Buffalo Dive team member is fast-paced and ever on the go. In fact, at the time of this interview with Weston Cross, he was sitting in an airport awaiting a flight to Okinawa, Japan, where he and his dive team colleagues will be performing inspections at the Naha military port and military facility at Whites Beach.
The Corps of Engineers Buffalo District provides full-scale diving services to partners across the United States and abroad. With an experienced staff of registered professionals, the group is qualified to perform services in-house as well as expeditiously award contracts to support your agency's mission. For more information about the dive team, visit http://www.lrb.usace.army.mil/Missions/Interagency-Support/Dive-Team/.