After catastrophic floods in 2012, China made recovering from floods and minimizing their damage a national priority. To achieve that goal, China is creating “sponge cities” – urban areas able to absorb and hold large amounts of excess water, gradually flowing it back into nature.
Only about one-fourth of the rain falling on Chinese cities is absorbed into the ground. The rest falls on roofs and impermeable pavements, flooding homes, streets and overflowing drainage systems, forming unhealthy pools in cellars, parking lots and grassy areas.
Now, 30 Chinese metro areas are experimenting with man-made retention lakes, roof gardens, more parkland and green space, and paving surfaces with permeable materials.
Because inner cities are already built up, newer spongy materials and innovative designs are being tried in outlying areas. More densely settled areas will be converted gradually as old neighborhoods are rehabbed or torn down and rebuilt with flood-resistant designs. An added benefit: More greenery improves the quality of city life, particularly by absorbing some of China’s notorious air pollution.
The government has mandated “water resilience,” but leaves it up to individual cities to find the best way to get there – and pay for it. Presently, Beijing is putting up only about 20 percent of the needed funds.
TRENDPOST: Cities, particularly along coasts, will be forced to adopt building codes that focus on resilience – not only in confronting floods, but heat, drought and other hardships brought on by extreme weather. New businesses and industries are cropping up to meet these demands.