Rethinking Infrastructure Design - Rethinking Infrastructure Design for Multi-Use Water Services - page 11

Fig. 11 Examples of rain gardens and multifunctional trees ( http://www.phillywatersheds.org )

Water storage, both natural (open water bodies such as retention ponds or
wetlands) or engineered ones (water tanks or water gardens), serve as run-off
control, but also provides opportunity for water demands to be met during longer
and more frequent dry periods.
The MUS paradigm is aimed at behaviour and perspective change. People have
to realise that water can be something beautiful, watering attractive

plants within low maintenance arrangements while providing habitat for wild life
and increasing amenity of space (see Fig. 11 ). In the US, the simple but powerful
idea of the multifunctional rain garden is spreading rapidly.

' drainage '

4.2 Water Pollution

What about the quality of water in our water streams? Indeed, most of the urban
run-off comes from roofs, streets and paved areas. Pollutants from vehicles
including oil, oil combustion products and heavy metals accumulate on sealed
surfaces and are washed into drains and ultimately into water streams following
rainwater. The water has to be filtrated before discharging. The solutions may be in

redirecting run-off water through the soil and vegetation (including tree pits), which
would enable natural microbes to remove pollutants before they reach drains or
streams. If geology allows, water can be in

ltrated to recharge groundwater or

over ow to conventional drains, which will reduce stress on sewers and water

treatment plants (Fig. 12 ).
It is a common misconception that sustainable drainage systems may not be
possible to deal with the amount of water or that at the least, need additional
over

ow protection or connection to a drainage system. However, integration of
MUS solutions such as rainwater harvesting, green roofs, rain gardens and other
features may be enough to retain complete participation run-off. Good example of
such solution is Potsdamer Platz in Berlin. The whole area is designed in a way for
all run-off to be intercepted and stored in underground storage or waterpark. In
10 years, there has been no run-off from the site.