As humans gravitate more and more to urban centres, we are paving over fields and forests and wetlands, burying streams and rivers and causing rain to fall on impermeable surfaces where it not absorbed back into the ground. Sponge cities were pioneered in China to help urban centres deal with flash floods and stormwater overflows made worse due to climate change.
Sponge cities design urban centres to absorb water and keep the city cooler during heatwaves. A number of Canadian cities are looking seriously at water retention designs. Another exciting concept whose time has come!
