• Engineering & Construction



Project Date



Southern BC

The LMIPSU project (Lower Mainland Intermediate Pressure System Upgrade) included the installation of a permanent sheet pile trench box beneath the Hwy 1 overpass on East 1st Ave, Vancouver, B.C. to accommodate a short section (i.e. 43m) of pipeline. Due to site restrictions and engineering guidance, it was determined that the pipeline excavation be within the confines of a reinforced sheet pile trench to ensure minimal impact on the overpass piers. The design required sheet pile to be driven to 7m depth using bolted splice plates, due to the restrictive overhead clearance (5m).

This project included the installation of steel sheet pile, excavation of material and reinforcement of the trench box with temporary and permanent bracing.  A detailed design and construction sequence was provided by the owner as well as complementary plans for traffic control, environmental management and overpass pier monitoring. The project was completed on schedule, avoiding any delays with pipeline construction company.

Scope of Work Provided by Landmark:

  • Pier and construction site monitoring throughout the project (using piezometers, inclinometers, accelerometers, tilt meters, and robotic total station to gather real time measurements and generate notification alerts),
  • Cutting and removal of asphalt surface,
  • Supply and installation of sheet pile (spliced and bolted),
  • Excavation and disposal of excavated soil,
  • Installation of sumps and disposal of site water,
  • Reinforcement of sheet pile walls with splice plates, walers, struts, and braces,
  • Placement of drainage gravel,
  • Turn site over to others for placement of construction sand, 30″ Intermeditae Pressure pipe, cellular concrete, and backfill.

Project Photos