NOTL Virgil I/I Study & Remedial Action Plan

Project Details
  • Location
  • Project Contact
    • Henry Szustka
  • Client
    Town of Niagara-on-the-Lake (NOTL)
  • Completion


This project was developed and completed by XCG Consulting Ltd. or XCG Consultants Ltd. In April 2017, Cole Engineering Ltd acquired the projects, history and resources of XCG’s Water and Training & Operations business.

Project Highlights

COLE developed an approach for I/I reduction to meet the needs of the Town of Niagara-on-the-Lake (Town) in a cost effective and timely manner recognizing the need to achieve real reductions in I/I through the completion of low cost repairs. The first phase involved the completion of a thorough flow monitoring study, which included flow meter and rain gauge installations and subsequent data analysis to determine areas having extraneous I/I contribution.  Catchment areas were priority-ranked.  Field investigations and inspections were carried out, starting with field surveys of roof downspout connections, low-lying areas, reverse driveways and runoff drainage. Select manhole inspections were completed documenting potential sources of I/I.

A Remedial Action Plan was then developed which included a review of CCTV data to identify sources of extraneous flow due to cracks, fractures, open/displaced pipe joints and other deterioration. This review identified the need for additional CCTV inspections in areas missing CCTV data. A Constructability Review was performed to determine the correct type of remediation.  The Remedial Action Plan included grout & seal and CIPP spot repair rehabilitation methods in numerous sewer sections. The Remedial Action Plan called for additional manhole inspections in select locations to identify extraneous flow around pipe connections, holes in walls/benching, cracks in barrels, risers and chimneys and other sources. Further field investigations confirmed downspout connections to either the sanitary or storm sewer system through a dye testing program.
A complete Tender Package was prepared for the sewer rehabilitation using the Town’s standard format. During the tendering process, assistance was provided in the preparation of the tender advertisement and responses to any technical questions.  Following tender closing, COLE reviewed the submissions and provided input to the Town on the award of the project. COLE is currently providing the Town contract administration and construction inspection services.
A post-rehabilitation flow monitoring program will be completed to assess extraneous flow reduction after system repairs are completed.