The 5 Minute Rain Garden

Rain & Stormwater

• Rain that falls in the native landscape…– Some is absorbed by trees– Some transpirates back into the air– Some flows under the surface to creeks– Some infiltrates back into the ground

• This is good :-)

In Towns…

• Rain falls onto roads and car parks– Picks up pollutants and flows into drains– Floods roads

• Rain falls onto roofs– Picks up pollutants and flows into drains

• The drains empty into the ocean

• This is all bad :-(

Rain Gardens

• A rain garden takes rain from the roof.– Some of this water is absorbed into the

ground.– Some transpirates back into the air.– The excess is bio-filtered and flows into the

storm drains.– Clean water now flows into the bay.

Designing a Rain Garden

• You need to calculate roof size drained.

• Know how much rain falls and when.

• Decide how much rain to allow for.

• Calculate how big a hole to dig.

• Set it out on the ground and dig it.

• Amend the soil and plant the plants…