1. URBAN HYDROLOGY

2. URBAN FABRIC RUNOFF PROCESSES AND DRAINAGE CHANNELS

3. Hardened surface promotes rapid surface runoff

4. Runoff channeled along roadside flows rapidly downhill

5. Many streams in urban areas are at least partially channelised

6. The Kuils River on the Cape Flats is typical of urban channels

7. URBAN STRUCTURE RUNOFF SURFACES AND DRAINAGE NETWORKS

8. Panorama of Grahamstown: note proportion of hardened v. vegetated surfaces and degree of connectivity between runoff surfaces and the main stream channel.

10. How does the hydrological response change in different areas of the town?

11. Riparian zone of Blaukrantz river; how connected is the river to the build up area?

12. Upper catchment of small urban stream

13. POLLUTION SOURCES

14. Litter in an urban stream; pollution derived from the catchment surface

15. Sewage works below King Willliamstown and Zwelitscha: Note Buffalo River in trees to the left of the sewage ponds.

16. Saline outflow from the Da Gama textile factory

17. DOWNSTREAM IMPACTS

18. Algal growth in Laing Dam

19. Water hyacinth in Laing Dam

20. FLOOD PLAIN TRANSFORMATION

21. The modern flood plain of the Ebro River, northern Spain

22. Zaragoza town in early days: impact on river channel and flood plain is localised

23. Modern Zaragoza: impacts now extensive

24. Flood walls protect urban development

25. REGIONAL IMPACTS

26. Gareip dam: source of water for Port Elizabeth and Grahamstown

27. WATER SUPPLY TO GRAHAMSTOWN