NYC Water Tunnel Shafts 21B and 22B
Brooklyn, NY  (1991)

KiSKA-USA made a vital contribution to the completion 
of New York City's $4 billion water system expansion 
with the timely construction of two 650-foot deep access 
shafts.  Like much of KiSKA-USA's work, construction of 
these shafts was undertaken in a dense urban setting 
where the solution to complex logistical and regulatory 
requirements was the key to the project's ultimate success.  
Typically, KiSKA-USA's engineers work with proven systems 
and technologies to minimize costs and avoid delays.

For the New York City water system, soft soil around the shafts 
was fully stabilized through ground freezing techniques down 
to bedrock at a depth of 220 feet below grade.  Despite the 
risks associated with large, subterranean construction projects, 
KiSKA-USA's safety controls insured a perfect safety record for 
the duration of the project.