HOUSING sustainable use of resources and the protection of ecologically sensitive areas as a focal point for future urban development. Integral to environmental planning is the creation of green belts, open spaces and parks – features previously confined to the affluent suburbs of the countr y. Prior to construction on Cosmo City, an environmental management plan set out a list of criteria for fulfilment by the developers and professional teams on the project. These included the development of: • an ecological management plan for the conser vation areas • environmental management plans for construction and operational activities on site • an environmental impact assessment report (focusing on heritage, geology, soil, hydrology and storm water attenuation) • a biodiversity report. Cosmo City environmental management Once these had been completed and construction started, all building activities on the site had to be strictly monitored by a full-time environmental control officer, prescribed in the environmental management plan and approved by the Gauteng Department of Agriculture, Culture and the Environment (GDACE). According to Kannenberg, ahead of the construction work nearly 21 000 protected and medicinal plants were transplanted to the Suikerbosch Rand Nature Reser ve and the indigenous vegetation on the Cosmo City site was preser ved in a 300 ha conser vation park, protected by a 42 km palisade fence. While it was inevitable that large tracts of natural vegetation would be lost in the development process, this was compensated for by planting trees and shrubs throughout the area. “The fact that the terrain was sandy was a challenge because of erosion. However, the grassing of municipal parks by the city council and the establishment of gardens throughout Cosmo City reduced the impact of this dramatically.” Basil Read Developments established a pilot nurser y at Cosmo City and trained staff to propagate trees and shrubs as part of its Green Projects programme. Using the latest innovative technology, the nurser y conducts ongoing research on, for example, the use of microorganisms
and earthworm farming to help create and maintain sustainable ecosystems. There is also continual cross-linking between these kinds of private programmes and municipal schemes aimed at making Cosmo City an environmentally cohesive development. For example, the City of Johannesburg, in its Climate Proofing of Urban Communities Project, installed 700 low-pressure solar water heater (SWH) units, distributed compact fluorescent lamps and fitted insulated IsoBoard ceilings in all the subsidised houses. This follows the first phase of
Construction of the main access road in progress
downstream properties along the banks of the Zandspruit,” explains Kannenberg. Using the Civil Designer software helped WorleyParsons facilitate the shared design of Cosmo City’s civil infrastructure, which the other joint venture partners also used. Cosmo City has nearly 130 km of internal streets and similar lengths of water pipes. The City of Johannesburg manages the essential services and maintenance of park and environmental areas. In its entirety,
Cosmo City is the kind of development envisioned in the city's Spatial Form and Urban Management Sector Plan installation of 170 SWHs in 2007 as part of the Department of Energy’s target for the provision of one million SWH units throughout the countr y within five years. The low-cost units have also all been fitted with prepaid water and electricity metres. Storm water management One of the most important aspects of the development, and critical to the first stages of the environmental impact assessment, was the storm water management. This was designed by WorleyParsons and its joint venture partners using Civil Designer’s storm water module application with its multiple pipe layer functionality for the capture of pipe layer data according to dimension and material. “The increased storm water runoff is attenuated by a series of carefully designed and placed attenuation dams, thus mitigating the effect thereof on the
Cosmo City is the kind of development envisioned in the city’s Spatial Form and Urban Management Sector Plan, of which the aim is to “create a physical environment that meets the current needs of communities, but also protects the interests of future generations”. As a point of reference for similar development models, the significant elements of Cosmo City’s success have been the strength of the public-private partnership, combined with the buy-in of the communities, whose ownership of the development, through the Cosmo City Residents Association, has created a sense of pride and sustainability. Talking of this key project in his 33-year career, Kannenberg maintains that it was a unique development at the time of its conception, and it has since been replicated as a model for integrated, mixed-use and sustainable housing.
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