Month: December 2016

Pipeline Condition Assessment

Job Location: National Park Service – Fort Jay, Governor’s Island, NY

Hennigan Engineering was retained to perform a Utility Pipeline Infrastructure Condition Assessment for the National Park Service on Governor’s Island in New York Harbor.  Our client for this project is a global engineering company that provides consulting, design, construction, and operations services for corporations, and federal, state and local governments around the world.  The firm ranks in the top 3 of  Engineering News- 2016 list of Top 500 Design Firms.

Fort Jay waGovenors Island NY


Upon completion of the work, Hennigan Engineering developed a detailed report that included down-pipe snapshots taken from the video and other graphics as necessary for the owner to understand the status of their storm and sewer system.  This included our recommendations to effect repairs and maintenance of the system in the future in support of the impending site rehabilitation.

The owner and our client have reported that they intend to re-engage Hennigan Engineering to execute the recommendations made in our Fort Jay report and also; to repeat this performance at Castle Williams on Governors Island in 2017.


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Specialized Concrete Hydro Demolition

Hennigan responds to customer’s request to remove 7 inches of overhead concrete from an intake bay under critical path schedule.  Hennigan completes 1st bay 7 days ahead of schedule, safely and under budget.

Hennigan Engineering Co., Inc. was called in to perform a concrete demolition operation at a Nuclear Power Plant after 21 days of jackhammering by another contractor failed to achieve the specified results.  The failed pneumatic demolition effort during this outage caused a work stoppage and steel reinforcing beams needing to be installed to allow the plant to operate an ICW pump bay.

Because of live electrical lines and numerous pipe interferences and other obstructions in the work area, robotic concrete demolition technologies could not be used.  Hennigan was hired to design a concrete removal system to remove overhead concrete material and allow the plant to make the necessary structural repairs to satisfy both the Nuclear Plant and NRC.

Hennigan Engineering designed a remote cleaning system that allowed individual tool operators the ability to hand control the path of the water jets, 40,000 psi was used to remove the concrete at high rates of production.

high pressure waterjetting
Before Hydro Demoliiton

In  addition to the ceiling removal, Hennigan personnel removed a thrust beam that housed pump bracing.

Hennigan Engineering was able to map out electrical lines using Ground Penetrating Radar (GPR) and safely hydrolase concrete to the desired depth without incident.

hydro demoltion
After Hydro Demolition Rebar Remains Intact


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