What is Water Sensitive Urban Design (WSUD)?

We offer maintenance and installation for many stormwater and WSUD devices such as Rainwater tanks, Biofilters, Pit inserts and OSD’s. But what exactly do these devices do and what is Water Sensitive Urban Design?

WSUD?

Water Sensitive Urban Design (WSUD) is a scientifically proven technology to effectively manage stormwater.

Why do we need WSUD?

Stormwater has a detrimental impact on waterways due to the excess nutrients and pollutants it carries. After the rain, stormwater flows down our waterways in large volumes, contributing to creek bed and bank erosion.

Social and environmental benefits of WSUD?

  • Improved health of waterways by filtering, reducing and slowing the flow of stormwater before it reaches local waterways.
  • Enhanced flora and fauna habitats.
  • Improved streetscapes and landscape attractiveness.
  • More green spaces established, reducing urban heat
  • Reduced reliance on drinking water

Common types of WSUD devices:

  • Rainwater tanks (with and without on-site stormwater detention)
  • Biofilters (also known as Bioretention systems or rain gardens)
  • Gross pollutant traps (GPTs)
  • Pit inserts
  • On-site stormwater detention (OSD)

Rainwater tank

A rainwater tank captures and stores roof water for reuse on-site. It may also play a part in local flood control.  It is important that the tank fills and empties regularly, as water stored in tanks for extended periods can become a health hazard. Regular inspection and maintenance are needed for your rainwater tank to run effectively.

Biofilters

Biofilters (also referred to as Bioretention systems or rain gardens) are engineered garden beds that filter stormwater runoff through a vegetated filter media. Treatment of stormwater occurs as the water infiltrates and soaks down vertically through the system, where plant roots and microbes in the soil naturally remove pollutants. Biofilters can be constructed as basins (in raised beds, planter boxes or at ground level), swales or medians, and will have the same inspection and maintenance requirements.

Gross Pollutant Traps (GPT’s)

Gross pollutant traps (GPTs) capture litter, sediment and debris that is washed into the stormwater system. Most GPTs are proprietary products that vary in exact form and function but are comprised of similar components.

Pit Inserts

These devices are fitted into stormwater drainage pits to capture litter, debris and other pollutants from urban runoff. They are often used as the primary treatment of stormwater before it enters a secondary or tertiary treatment system.

On-site Stormwater Detention (OSD)

On-site stormwater detention is the temporary storage and controlled release of stormwater generated on-site. OSD temporarily stores and slows down the rate of stormwater runoff from a property so that it does not worsen flooding downstream, whereas a rainwater tank stores rainwater for reuse purposes.

OSD systems can be located above ground or below ground. They should remain empty except during periods of rainfall and shortly after the rainfall ceases. Ponding of water should not last for more than 2 hours in most rain events. If ponding persists, it is likely that maintenance attention is required.


Stormwater Sydney provides Inspection, Cleaning, Maintenance, Repairs, Construction, and Advisory on stormwater systems across Sydney. Ensuring you comply with Council and EPA requirements