What Causes a Storm Drain to Clog
Leaves, roof grit, soil and yard debris wash into the drain grate and settle in the pipe. Over time the build-up narrows the channel until water can no longer pass at the rate a heavy rain delivers it.
Tree roots find the moisture at pipe joints and push through small cracks, which turns a surface clog into a structural one. Grease and silt from driveways can also harden inside the line.
Warning Signs of a Blocked Storm Drain
Standing water in a driveway, patio or yard after rain is the clearest sign. Water staining on a foundation wall or a damp basement corner often follows.
Gurgling sounds from the drain during rain, or a grate that overflows while neighbours stay dry, point to a blockage in your section of the line rather than the street main.
What You Can Safely Do Yourself
Clearing leaves and visible debris from the grate with a rake or gloved hand is safe and often restores flow. Keep the area around the drain clear before heavy rain.
Do not open a drain cover or enter a drain chamber. Confined spaces can hold dangerous gases, and underground work needs a licensed plumber with the right equipment.