Stormwater is rain, melted snow or any other form of precipitation that has come into contact with the ground or any other surface. This water either seeps into the ground, is absorbed by vegetation, evaporates or runs off the land into storm sewers, streams and lakes.
Stormwater can come from any type of land – residential, industrial, commercial or institutional.
Stormwater must be managed for two key reasons:
But we humans have interfered with this cycle – precipitation can't reach the soil through the hard surfaces we build such as roads and buildings. We've also built storm sewers to quickly drain that water away.
Municipalities and developers create strategies to prevent stormwater pollution and design systems to treat stormwater and route it safely back into our natural environment.
There are many benefits to stormwater management. It supports environmental sustainability by:
Stormwater management also contributes to community safety and financial risk management by reducing the risk of urban flooding and erosion. The associated basement flooding and damage to public and private properties can also be avoided (in conjunction with major drainage systems built by municipalities).
Please explore the rest of this section to learn what stormwater management involves, find out what municipalities and property owners need to know about stormwater management, learn how we're adapting stormwater management for climate change, encouraging the creation and export of innovative clean-water technology and promoting water conservation.