Impacts of Urbanization on the Water Environment Decrease in forest and grass cover Decrease in water conservation and storage capability Decrease in paddy and pond area>Decrease in rainfall storage capacity Increase in nonpermeable land surface>Decrease in infiltration and increase in runoff Population growth and concentration>Increase in demand for water supply and wastewater treatment Before Urbanization After Urbanization
Before Urbanization After Urbanization Decrease in forest and grass cover ➔ Decrease in water conservation and storage capability Decrease in paddy and pond area ➔ Decrease in rainfall storage capacity Increase in nonpermeable land surface ➔ Decrease in infiltration and increase in runoff Population growth and concentration ➔ Increase in demand for water supply and wastewater treatment Impacts of Urbanization on the Water Environment
How Do Humans Change the Water Cycle? 0 1-3% 4-40% 41-100% .US-impervious surface area/person (297m2)(Range 0-400 m2/person U.S.average 1.05%(Elvidge et al.2007)
How Do Humans Change the Water Cycle? •US - impervious surface area/person (297m2) (Range 0-400 m2/ person ) •U.S. average 1.05% (Elvidge et al. 2007)
Impervious Cover Stream Quality (Center for Watershed Protection) Relationship between Impervious Cover and Stream Quality 70 60 50 Non-supporting (>25%) 40 20 Impacted (11 to 25%) 10 Sensitive (0 to 10%) 0 Good Fair Poor Level of Stream Quality
Impervious Cover & Stream Quality (Center for Watershed Protection) Relationship between Impervious Cover and Stream Quality 0 10 20 30 40 50 60 70 Level of Stream Quality Watershed Impervious Cover (%) Good Fair Poor Non-supporting (>25%) Impacted (11 to 25%) Sensitive (0 to 10%)
Urbanization and Water Water resource scarcity 。Vater pollution 。Urban Waterlogging
Urbanization and Water • Water resource scarcity • Water pollution • Urban Waterlogging
