The Problem

What a Summer Storm Did to This Scarborough Home

Over 60 millimetres of rain fell within two hours during a severe summer storm, overwhelming municipal storm drains throughout the neighborhood. Water backed up through a below grade window well that had a failing seal, pouring into the basement faster than the homeowner's sump pump could keep up. Within 20 minutes, standing water covered most of the unfinished basement floor and had begun soaking into stored belongings and the bottom of framed storage shelving.

• Standing water across an 800 square foot unfinished basement
• Water entry through a failed window well seal during peak storm intensity
• Sump pump overwhelmed by the volume and speed of the inflow
• Stored belongings and cardboard boxes saturated near the point of entry
• Water approaching electrical outlets along the basement's lower wall

Why It Happened

Why Storm Flooding Is a Growing Risk for Scarborough Basements

Scarborough's storm sewer infrastructure in many older neighborhoods was not designed for the intensity of rainfall events becoming more common across the GTA. When a short, intense storm drops a large volume of rain in a short window, municipal drains can back up faster than individual home drainage systems can compensate, particularly at points of vulnerability like window wells, foundation cracks, or aging seals. A single sump pump, especially without battery backup, can also be overwhelmed when inflow volume spikes suddenly rather than rising gradually.

• Storm intensity exceeded the capacity of neighborhood storm drains
• Window well seal had degraded and was not caught during routine home maintenance
• Sump pump lacked battery backup for periods of peak inflow
• No secondary drainage or backwater valve installed at the point of entry
• Basement grading around the window well allowed surface water to pool before entering

Our Process

How Emergency Flood Services Responded to This Scarborough Flood

1. Rapid Emergency Response — Our team arrived within the hour despite storm conditions across the city, prioritizing active flooding calls.
2. Water Extraction — Submersible pumps and truck mounted extraction units removed standing water from the basement within the first hour on site.
3. Window Well and Seal Assessment — Our team identified the failed seal as the point of entry and recommended repair alongside our restoration work.
4. Structural Drying and Sanitization — Air movers and dehumidifiers dried the concrete slab and surrounding framing, with sanitization applied given the storm water's contamination risk.
5. Content and Belongings Assessment — Affected belongings were assessed, with salvageable items cleaned and dried and unsalvageable items documented for the insurance claim.

Prevention

How to Protect Your Scarborough Basement From Storm Flooding

• Inspect window well seals annually and repair or replace before they fail
• Install a battery backup for your sump pump to maintain function during power outages or peak demand
• Consider a backwater valve if your home is in an area prone to storm sewer backup
• Grade soil and landscaping away from window wells and foundation walls
• Keep basement storage off the floor using shelving to limit damage from minor water intrusion