What is stormwater?
When it rains, water can’t soak through the hard, impervious surfaces such as pavements, road and car parks that surround us in towns and cities. Instead, the rainwater travels across these surfaces and is channelled into a network of drains. The water entering these drains is known as stormwater.
What’s the difference between the stormwater system and the sewer system?
The stormwater system is designed to transport clean rainwater. Rainwater is collected in stormwater drains and carried through a network of pipes, which then flows into our streams and rivers. Stormwater doesn’t get treated, so whatever goes into the drain will end up in the nearest stream or river.
The sewer system is designed to take household waste water, such as water from showering, flushing the toilet and doing the laundry. This dirty water flows through a network of pipes to a treatment plant, where it is treated to make it safe before being released back into the environment.
Where does water go after it drains into a stormwater drain?
From a drain, stormwater travels through a network of pipes, which eventually discharges untreated into local waterways. So whatever goes into the drain will end up in our rivers and streams.
How does stormwater affect the quality of rivers and streams?
Stormwater picks up pollutants such as dirt, oil, chemicals and litter as it travels across impervious surfaces. Because stormwater doesn’t get treated, all these pollutants end up in our streams and rivers, where they reduce the quality of the water. This can make the water unsuitable for swimming or drinking and makes it difficult for plants and fish to survive.
How does stormwater get polluted?
Stormwater picks up pollutants from the surfaces it travels across on its way to a stormwater drain. The pollutants can come from all different sources, such as:
What can I do to help?
Get involved! Follow the top tips on this website to make sure you and those around you are keeping our waterways clean. Talk to people at your work or school about the things you can do in your area
What do I do if I see someone dumping into a stormwater drain?
If it’s someone you know – tell them that what they’re dumping is going to end up in your nearest stream or river, and encourage them to do the right thing. If you see a stranger dumping into a stormwater drain, call Environment Canterbury’s Pollution Hotline on:
0800 76 55 88.