Basement level plagued by water seepage, delaying construction of final building in redevelopment project
By: Marjorie Censer
A new solution for the seepage in the basement of the Spring Street garage is in the works, and Princeton Borough Administrator Robert Bruschi said he may receive a proposal as early as the end of the week.
The garage part of the downtown redevelopment has been plagued by a wet basement since it opened in 2004, and the borough and developer Nassau HKT have been in discussions about the best way to repair it. Mr. Bruschi said a new solution has been proposed that appears to satisfy both Nassau HKT and the borough.
Robert Powell, principal of Nassau HKT, said the intended fix has two elements. First, the garage’s structure will be strengthened using rock anchors.
The anchor bolts will attach the concrete slab to bedrock, Mr. Powell said, to "stop any of the flexing of the slab that is currently occurring."
He said he expects that step alone to eliminate most of the water seepage, but new plans also call for grout described as an expanding foam insulator by Mr. Bruschi to waterproof the slab.
Mr. Powell said the details of the solution have not been completed, but Nassau HKT is in talks with several contractors. He said he hopes to receive price estimates in the next few weeks.
Mr. Bruschi said the borough’s independent consultant has reviewed the proposed solution and thinks it is reasonable.
The repair proposed in the past was a "sandwich slab" that would cover the lower level concrete slab. That solution would have reduced the height of the basement level.
Nassau HKT remains in discussion with garage designer HNTB Architects about the cause of the water seepage, Mr. Powell said. An independent analysis received in August suggested that the garage’s design caused the problem, but HNTB denied responsibility.
The borough will not allow work to begin on Building C the proposed five-story, mixed-use building on the site of the Tulane Street parking lot until the garage’s basement is available.
The downtown redevelopment project includes the Spring Street garage, Witherspoon House and its accompanying plaza, and Building C.
The remainder of the downtown development is virtually complete. Mr. Powell said he still is waiting for the pergola planned for the plaza. The pergola is available for installation, he explained, but the construction crew is still waiting for the removal of a utility pole from the plaza’s southern end. Mr. Powell said Nassau HKT has made repeated phone calls to Verizon and agreed to pay the cost of the pole’s removal, but is waiting for the company to develop a plan for taking it down and submit an estimate.
Witherspoon House is fully occupied, except for the restaurant planned for the ground level, and Mr. Powell said he expects a "soft" opening in December. Jack Morrison, a partner in the downtown redevelopment and owner of the as-yet-unopened Witherspoon Grill, could not be reached for comment.

