Methodology
Ventilation and odor control used:
Fresh air pumped into pipe past upstream air dam; maintained sealed lids during non-work periods, and adequate ventilation to carry odors downstream during the work periods.
Rehab method used:
Danby Panel Lok III in top portion of pipe from 12" below the pipe centerline, with full annulus grouting with cementitious grout with minimum compressive strength of 5000 psi. Prior to installing liner, 4"x4"x1/4" welded wire mesh was mechanically fastened to pipe wall in those areas were the wall corrosion exceeded 2".
Cleaning method used (if required) and who cleaned the line:
High pressure (18,000 psi) water blasting performed by the Danby licensee (Rondeau Bay Construction).
Method of flow bypass or diversion, if used:
Constructed work platform over low flow level and partially regulated flow at pump plant.
Hurdles
Problems encountered during construction:
Significant diameter increase at crown after high pressure water blasting due to corrosion created enlarged annulus far exceeding the original estimate of surface wall loss; thus increasing the amount of welded wire mesh and grout required to meet the specification. Also, in these very large diameter pipes the grouting must be done in many more "lifts" (to limit vertical rise per lift) to avoid deforming the PVC liner.
Problems encountered after construction:
None
