OPWA Booklet I Design 2025 (4) - Flipbook - Page 26
EMERGENCY CONSTRUCTION / REPAIR
> $10 MILLION
CITY OF MARKHAM| MONTROSE ENVIRONMENTAL COMPANY |
R&M CONSTRUCTION
John Street at Settlers Park - Erosion Restoration
On August 18, 2024, the John Street road embankment at the entrance
of German Mills Settler Park in Markham failed, causing significant
scour along the slope, undermining the sidewalk and trail, and exposing
a gas main.
Emergency work was completed immediately to secure the gas main
and prevent further slope collapse. A bypass pump was installed to
maintain stormwater flow until a permanent solution was implemented.
In September, the City hired Montrose Environmental (formerly Matrix)
for detailed design and contract administration, followed by R&M
Construction in November for construction of a permanent solution.
The project aimed to restore the sidewalk and trail, stabilize the road,
protect the exposed gas main, and reinstate stormwater flow while
improving drainage to reduce future failure risks.
Public notices and signs were used to redirect pedestrians around the
sidewalks and this busy trail system. Traffic disruptions were
minimized by scheduling work outside rush hours and using park space
for staging.
Since the site falls within the TRCA Regulation limit, TRCA staff were
consulted, and an emergency permit was granted while the full
application was being prepared. ESC measures, including heavy-duty
silt fencing and fiber rolls, were implemented to protect German Mills
Creek.
To enhance longevity, the original CSP pipe was replaced with a High Performance pipe. Spray-in-Place Pipe
Liner technology was used for a portion of the pipe to avoid deep excavations adjacent to the road. A drop
structure was incorporated to lower outlet velocities, minimizing erosion.
Substantial completion was achieved in December 2024.
26 | OPWA AWARDS LUNCHEON
