Content of Sponge City Construction

Investment cost (10,000 RMB/y)

Maintenance cost (10,000 RMB/y)

Conventional model

Sponge city model

Conventional model

Sponge city model

Total

21,860

18,426

876

831

1) Construction and operation maintenance

in residential area

3960

5576

96

144

a) Roof greening

0

200

0

18

b) Pavement (hard/ permeable)

1440

2160

15

30

c) Green space (traditional/ecological)

2160

2520

65

72

d) Green belt (traditional/grass planting ditch)

360

396

16

18

e) Rainwater storage device

0

300

0

6

2) Construction and maintenance of rainwater pipe network and pump station

6500

3900

360

340

3) Watercourse ecological construction and maintenance

5100

4500

270

250

4) Construction and operational maintenance of wastewater pipeline and wastewater treatment plant

4500

3250

141

91

5) Construction and operational maintenance of waterlogging prevention facility

1800

1200

9

6