Rondout-West Branch Bypass Tunnel (BT-1)
This New York City Department of Environmental Protection (NYCDEP) project, Rondout-West Branch Bypass Tunnel, is a roughly $120M project to repair leaks in the Delaware Aqueduct. The first contract in this $1 billion program included site preparation in both Newburgh and Wappingers, and the sinking of two new shafts which would allow for the construction of the 2.5 mile bypass tunnel under a follow-up contract. The launch and reception shafts were 900 and 700 feet deep respectively, and approximately 30 feet in diameter.
HVEA was responsible for the design and trial batching of a specialty concrete mix in our AASHTO Accredited Laboratory. The mix had to meet workability requirements and achieve design strength quickly to maintain the contractor’s schedule without generating excessive heat during mass placements. During trial batching, representatives from the Owner, the Owner’s third-party concrete testing firm, the Contractor, and the Construction Manager witnessed the operations. HVEA tested fine and coarse aggregates and evaluated the results of 14 different mix designs. Following a full array of tests, HVEA determined the acceptable trial point and made recommendations for a production concrete mix to the client and owner.