The Wastewater infrastructure index provides an overall summary of the response towards waste water treatment in Greater Johannesburg.   Wastewater is collected from all domestic, commercial and industrial properties in the central city by making use of an extensive underground sewer systems.

• The Water Boards, governed by the Rand Water Act (RWB Statutes Act), sells water to local authorities and also reticulates to individual consumers outside of local authority areas. In the past the former Regional Services Councils (RSC) might have assumed the regional water supply / distribution function, but Rand Water will retain this responsibility. The Department of Water Affairs is involved in large water schemes for both urban and agricultural uses and also sells bulk water to Water Boards or municipalities (GJMC, 1996).
• In terms of the legislation Water Boards are able to own and operate Waste Water Treatment Works (WWTW). Previously, the Regional Services Councils had the option to assume a regional function of wastewater conveyance and treatment. Today local authorities are responsible for water and sewer reticulation and storage within their own boundaries. Water Boards may resist expanding their supply to regional boundaries since supply at the margin is more expensive than the average cost of supply.
• The existing supply infrastructure was designed and constructed to conform to the boundaries of the former local authorities. The current Metropolitan Local Council (MLC) boundaries may therefore fall under different reservoir supply zones and reticulation networks. The former Johannesburg Administration acted to a limited extent as a bulk supplier of water within the Central Witwatersrand area, providing bulk supplies of water through its storage and distribution system to Lenasia South-East, Soweto, Diepmeadow, Alexandra and Bedfordview. Rand Water is responsible for the abstraction and treatment of raw water, which is distributed in bulk to local authorities at a fixed tariff. Rand Water supplies 81 bulk supply meters to the GJMC (GJMC, 1996).
• The water supply system consists of various elements including bulk conveyance from Rand Water supply points to local storage facilities (reservoirs, water towers, pump stations, bulk distribution mains and local reticulation mains) conveying water to the end user.
• The distribution of water is based on reservoir zones with reservoirs sited at predetermined levels within the local authority. This will ensure adequate minimum pressures and prevent excessively high pressures within the distribution system. The system is further broken down into water loss control zones within reservoir zones to monitor and control water losses. The planning, design and operation of the system are based on these zones. The boundaries of theses zones have been determined by existing or former political boundaries and to some extent by the incremental development of townships within former local authorities which have now been incorporated into the Metropolitan Council’s boundaries.
• The GJMC is also responsible for the bulk function of the provision and management of wastewater treatment and conveyance in bulk outfalls.
• Approximately 600 million liters of sewage is treated daily by different plant works in the Greater Johannesburg area:

1. The Northern Works in the north, and

2. The Bushkoppies, Goudkoppies and Olifantsvlei Works in the south.

• Wastewater emanates from the old administrative areas of Alexandra, Johannesburg, Randburg, Roodepoort, Sandton, Greater Soweto, Ennerdale and Lenasia. Approximately 95 % of the former Johannesburg area’s residents have access to waterborne sewerage systems, operated by the Council. The plants all operate on the so-called activated sludge system: a biological process specifically designed to remove major pollutants like carbon, nitrogen and phosphorous from the wastewater. By removing all the impurities it will be suitable for discharge into the river system.
• Approximately 10% of the recycled water is used as power station cooling water and 8% for irrigation of farms owned by the Council. The remainder is discharged into the Jukskei River in the north and the Klip River in the south (GJMC, 1996).
• Wastewater can be purified either by using expensive chemical processes or by using less expensive biological processes. The latter processes are very similar to those occurring in natural water bodies and are nature’s method of disposing of waste matter. Today wastewater treatment plants are used to compact and accelerate natural processes using engineering and scientific knowledge. The aim of any biological water treatment process is to purify the wastewater by using the organic and inorganic nutrient components of the wastewater as a food source for micro-organisms.
• Greater Johannesburg have achieved a lot in terms of service delivery between 1995 and 1998 (GJMC, 1999):
  * The development of modern housing units for staff have been done at the Bushkoppies Treatment Works to replace the outdated hostel accommodation.
  * The outfall sewer has been constructed for the Poortjie community, which enables the provision of waterborne sanitation for the township and the surrounding area.
  * Waterborne sanitation was provided for the Sweetwaters and Weilers Farm Reception areas. Once again, this not only improved living conditions and the health of the residents, but also opened up the catchment development.
  * Phase 1 of the South Western Outfall Sewer is well underway. Construction of 12 km of sewer has already taken place, giving additional capacity and allowing the full utilisation of the entire Outfall Sewer, which handles flows from the western part of Soweto allowing upgrading and permanency, and parts of Roodepoort and the south and west parts of Soweto for new development.
  * The Protea-Emdeni Sub-Outfall, which drains the western parts of Roodepoort, was upgraded to an acceptable and unified standard. This has improved drainage and reduced sewage spills.
• There were also some achievements in wastewater management (GJMC, 1999):
  * Creation and implementation of a strategic computerised planning model, based on GIS, which is used to determine the provision of new bulk water and wastewater supply, conveyance and treatment accross Greater Johannesburg.
  * A new sludge composting plant was successfully commissioned in June 1997, to produce materials for reuse in horticulture, land reclamation and agriculture.
  * A major refurbishment of the Driefontein Works, which started in 1996, has been undertaken. This has abated environmental pollution in the area, improved performance and reduced costs.
  * The refurbishment of mechanical and electrical equipment at Goudkoppies Works was completed in August 1996. This has greatly reduced the use of expensive chemicals for phosphorus removal.
  * Transferral of the Ennerdale Works to the Metropolitan Council and the introductions of a performance-based operating system resulting in the reduced running costs and mechanical upgrading.
  * A major extention was carried out on the Olifantsvlei Works and was completed in April 1997. This included an inlet pumpstation for the new south-western outfall sewer. The extention produced a good performance, with the effluent standards complied with for 90% of the time.

As Greater Johannesburg is situated far from the major river systems, the purification of its wastewater to high standards is absolutely necessary.

• The various MLC’s are responsible for sewage treatment in their areas. This sewage is treated either in the Northern or the Southern treatment plants according to the location, which are both under the responsibility of the GJMC.

Therefore Greater Johannesburg faces major challenges regarding the provision of water and sewage.

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