Corrosive Environment Forces Innovative Solutions In Denver

September 2009 Vol. 64 No. 9
A manhole after rehabilitation.
  • A saw cut in surface pavement was made to expose the perimeter of the existing manhole barrel;
  • Excavating around the existing cone section allowed removal of the cone;
  • The plug assembly was installed to manage wastewater flows;
  • Existing coatings and liners were removed from base sections and the invert area;
  • Complete surface preparation of base, benches and invert area by abrasive blasting and pressure washing;
  • Base, benches and invert area were rebuilt with C 120 calcium aluminate mortar and applicable reinforcing bars;
  • SewerShield 100 epoxy was applied to rebuilt portions of the structure;
  • Plug assemblies were removed to restore flows to rehabilitated invert;
  • The SewerShield composite manhole insert (barrel and cone section) was installed; inserts were specifically manufactured for each structure;
  • Annular spacing between the existing structure and new composite insert were filled with hydrophobic polyurethane grout;
  • Backfill around new composite cone sections was completed and paved surfaces restored;
  • And last, coated surfaces were spark tested and visually inspected in the presence of a project owner representative to detect any pinholes, which were patched as necessary.


Fisher Company Inc., (970) 887-9006,
SewerShield by Environmental Coatings, (480) 984-7608,
Plug-It Products, (800) 575-8448,