Black Rock Lock’s Dewatering Pumps Repaired and Back in Position

Published March 14, 2016
One of two 3,000 pound pumps are lowered 40-feet down into their casings.

One of two 3,000 pound pumps are lowered 40-feet down into their casings.

The two dewatering pumps repaired and replaced.

The two dewatering pumps repaired and replaced.

After a month of ongoing routine maintenance repairs, at Flygt Pumps in Rochester, NY, two dewatering pumps were safely and successfully re-installed back into the Black Rock Lock’s pump house, March 11 by the U.S Army Corps of Engineers (USACE), Buffalo District.

“Both pumps underwent standard maintenance, replacing bearings, seals, oil, and were repainted,” said Project Manager David Mastriano. “It was not known the amount of damage the pumps had sustained until they were opened up, but luckily the damage was minimal.”

One of the pumps had been cavitating for over two months during the last dewatering. It was determined during the event by the USACE Buffalo District New York/Pennsylvania Operation and Maintenance section that the pumps could not be shut down or the lock would fill back up with water. Cavitation is when the pump operates in a low pressure manner where air bubbles in the water collapse, and could lead to pitting and deterioration of pump surfaces, typically the impeller.

“Luckily, the pump never had a catastrophic failure during this period and the impeller was not damaged,” said Mastriano.

It was no easy feat removing, transporting, and replacing the two 3,000 pound pumps, but the Lock Wall team, directed by Lockmaster Tom Braunscheidel, handled the task without incident and with surgeon-like precision.

David Mastriano, David Bognar, Chuck Jensen, and John Barron worked as a team along with the contractor SAF (Akron, Ohio) to move, hoist, position, and lower each pump 40-feet into their casings. After the pumps were lowered and positioned atop their casings, SAF bolted the pumps into place. Next, wiring will be reconnected by Flygt and the pumps will undergo testing.

Every once and a while the 102 year-old lock has to be dewatered for maintenance and inspections. Now that the pumps are back in operation, dewatering of the lock may take place as the need arises, and without concerns of failure.

The lock is scheduled to be dewatered within the next few years to replace the pintle balls, which the 150,000 pound gate sits on and pivots at the bottom of the chamber. The gates will have to be disconnected and jacked up close to three feet to accomplish this task.

Maintaining the Nation’s aging infrastructure requires an extra level of tender loving care. The skillful efforts by USACE Buffalo District NY/PA Operations and Maintenance section ensures that the lock will continue to remain in operation and serve the navigating and shipping communities.