Stormwater is the water that runs off surfaces when it rains. It may fall on to the roof and be directed through gutters and downpipes, or directly onto surfaces including roads, gardens and driveways.
In the city, this water runs down drains into underground stormwater pipes and is carried to the nearest waterway – stream, beach, harbour or wetland. This water is not treated along the way, so it is important that it remains as clean as possible to protect the health of our waterways and marine life.
The purpose of a city stormwater system is to prevent flooding and provide a safe, contained way for water to drain away from populated areas, but increased urbanisation, rapidly growing city sizes, and changing weather patterns are putting extra pressure on the system, meaning additional stormwater management solutions are often required.
Did you know?
In a natural landscape rainwater surface runoff averages about 27% but in urban areas, due to the increase in hard surfaces such as roads, driveways and reduced vegetation, average runoff is in the region of 58%.
What causes pressure on the stormwater system and what are the effects?
- As infrastructure is developed, the number of impervious surfaces such as concrete, asphalt and roofing are increased, and natural surfaces and vegetation are reduced. This decreases the amount of water that can soak into the ground and reduces the number of plants that would normally help to absorb moisture. As a result, the flow of stormwater into drains is increased which can cause flooding and increase erosion of waterways and coastal environments.
- Due to human activities including traffic, housing and industry, stormwater can carry contaminants into waterways, causing pollution. As the water flows to the drains it is contaminated by things including herbicides, soil, detergent from car washing, oil residue from driveways, human and animal waste, household cleaners etc. All of these are swept up in the water and transported to the environment.
- The changing weather patterns and global warming is resulting in longer, heavier bursts of rain can overwhelm systems and increase the risk of flooding.
What can we do to ease the pressure on Council stormwater systems?
A stormwater detention tank is a safe and easy way to improve the management of stormwater on your property and, in turn, reduce the pressure on the Council stormwater system. A detention tank, such as the stormVAULT by Devan Plastics, is a tank that is intended to remain empty except for during periods of rain. When it rains, the tank collects stormwater and releases it at a rate specified by design into the council stormwater system. Take a look at the Devan stormVAULT range and contact us for more details.