A Bethlehem firm will perform emergency repairs to the Lehigh Canal in Allentown.
Joao & Bradley Construction Company has been awarded a $126,750 contract from the city of Allentown to make the repairs which include replacing a 17-foot deep manhole.
The canal failed on April 6 in the area of Lock No. 1 off the Lehigh River and is draining through the bottom to a broken more than 100-year-old 42-inch stone arch cross culvert.
Ongoing deterioration of the underlying cross stone arch culvert pipe could lead to a more catastrophic failure and higher replacement and retirement costs for the existing pipe.
City engineering prepared a design solution, scope of work and related tasks which were submitted to the Pennsylvania Department of Environmental Protection (PADEP) and approved for an emergency permit.
The canal repair must include a cofferdam and canal flow pipes in order to isolate the canal water away from the failure zone/sinkhole area prior to proceeding with a new manhole and 36-inch high density polyethylene pipes (HDPEP) watertight pipe installation and ultimately filling the broken pipe with a flowable fill to prevent further failures.
A new manhole facilitates the design and corrects other existing pipe and manhole failures on the east bank of the canal.
The cofferdam, manhole replacement, cross pipe and flowable filling of the existing stone arch culvert must all be performed as one continuous operation by one contractor as the cofferdam and cross pipe must be manipulated by the constructing contractor in order to cross the canal.
The estimated time to complete the cofferdam and restore canal flow is within the next two weeks. The estimated time to complete the installation of the new cross pipe beneath the canal, construct the new manhole, and fill the failing stone arch culvert with flowable fill is less than six weeks.
The canal is closed for recreational purposes, but Lehigh Canal Park remains open to visitors.