• The key driving forces in Greater Johannesburg are population growth, urbanisation, industrialisation and mining, and to a lesser degree agriculture.
• Exotic species in gardens alter the drainage patterns, the amount of runoff and erosion. A bluegum tree for instance evapotranspirates up to 150 litres of water per day. Exotic species also take over indigenous species and may destroy established ecosystems.
• Large areas also continue to be exploited for the location of squatter settlements and mining activities, and this reduces the conservation potential of these areas.
• Further population growth and development also encroaches on the natural habitat of many species of fauna and flora, reducing their chance of survival. This results in many species becoming endangered and eventually extinct.
• The slow rate at which people are obtaining access to effective water services and the lack of education about the efficient use of this service, is contributing to continued wastage and loss of water.
• Population growth and development in the city and its surroundings are threatening this scarce resource, while the implementation of laws and policies is problematic.
• Up to 200 litres of water are used per person per day, particularly in the more affluent parts of the metropolitan area. In the poorer communities and informal settlements, a lack of water and education on its use are the main driving forces, while ignorance and wastage creates problems in the affluent northern suburbs.
• Population growth and industrial development are placing extreme pressures on energy consumption.
• The north-western areas of the metropolitan area are rapidly being encroached on by the extensive housing development in the area. There is presently no coherent plan to integrate environmentally suitable land into a sustainable system. Legislation is needed to support environmental planning (WMLC: LDO, 1997).
• The increasingly built up nature of the local environment has altered the hydrology of watercourses. Increased impermeable surfaces, stormwater systems, soil compaction and the decreasing number of natural water retention systems have speeded up the delivery of water into watercourses. Water flows therefore peak faster and flood level lines have thus been extended (NMLC: LDO, 1997). Numerous developments already fall within the 1 in 50 year flood line, and the increasing amount of development around water courses is increasing the number of flood events.
• Business nodes of increased activity are being developed in close proximity to conservation areas.

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