ERS 482/682 (Fall 2002) Lecture 19 - 1

Urbanization

ERS 482/682Small Watershed Hydrology

ERS 482/682 (Fall 2002) Lecture 19 - 2

Figure 11-14: Dunne and Leopold (1978)

ERS 482/682 (Fall 2002) Lecture 19 - 3

Effects on hydrology

AuroraReservoir

ERS 482/682 (Fall 2002) Lecture 19 - 4

ERS 482/682 (Fall 2002) Lecture 19 - 5

ERS 482/682 (Fall 2002) Lecture 19 - 6

Effects on hydrology

• If storm size stays same (e.g., 2-year storm with 1 inch rainfall)– More runoff– Higher peak flows– More perennial flow

ERS 482/682 (Fall 2002) Lecture 19 - 7

Impacts on receiving waters

• Increased channel erosion– Reduced habitat– Reduced wetlands

• Increased flooding downstream

ERS 482/682 (Fall 2002) Lecture 19 - 8

Impacts on water quality

• Increased loading of– Suspended solids– Nutrients– Heavy metals– Fecal bacteria

ERS 482/682 (Fall 2002) Lecture 19 - 9

“Remedies”

• Best Management Practices (BMPs)– Practices that are a combination of

management, cultural, and structural approaches that most effectively and economically control urbanization effects without disturbing the quality of the environment

ERS 482/682 (Fall 2002) Lecture 19 - 10

“Remedies”

• Best Management Practices (BMPs)

Source: http://www.cwp.org

ERS 482/682 (Fall 2002) Lecture 19 - 11

“Remedies”

• Best Management Practices (BMPs)

Source: http://www.cwp.org

ERS 482/682 (Fall 2002) Lecture 19 - 12

“Remedies”

• Best Management Practices (BMPs)

Figure 11-17: Dunne and Leopold (1978)

ERS 482/682 (Fall 2002) Lecture 19 - 13

“Remedies”

• Best Management Practices (BMPs)

Figure 11-22: Dunne and Leopold (1978)

ERS 482/682 (Fall 2002) Lecture 19 - 14

“Remedies”

• Best Management Practices (BMPs)

Figure 11-19: Dunne and Leopold (1978)