June 27, 2002
By Lucille Davie
A CITY-BACKED test of Johannesburg's rivers and streams indicates that the quality of water in a number of "hotspots" across the city is "bad" or "unacceptable".
The testing, carried out by Water Quality Management, a division of the City of Johannesburg's Development Planning and Environment Directorate, is ongoing and covers all 11 regions of the city.
Some 117 water samples of Johannesburg's rivers and streams were tested during the period November 2001 to January 2002. The test did not involve sources of ordinary tap or drinking water, but water courses near industries, overcrowded informal settlements and mines.
Reports on the Jukskei River and its tributaries described the water quality of 87% of samples as "bad" and "unacceptable", while the water quality of 67% samples were "bad" and "unacceptable" in the Klip River catchment area. The main sources of pollution are sewage, mining activity and industry.
Two rivers drain from the central ridge of Johannesburg - the Klip River in the south, and the Jukskei River in the north. These rivers and their tributaries are tested for their bacteriological and chemical quality in the quarterly Water Quality Monitoring Programme, which tracks the results.
The programme also monitors the remediation measures taken by Johannesburg Water, the Johannesburg Roads Agency, Pikitup, Environmental Health officers and mine owners - and reports are that these measures are beginning to yield results.
Jukskei River catchment
Surface water in the Jukskei catchment is monitored at 71 sampling sites; 40 samples are taken monthly and 31 fortnightly. The aim of the monitoring is to "best capture the overall water quality" which is subjected to drainage from the CBD, industry, suburban developments, informal settlements and effluent discharged from the Northern and Driefontein Wastewater Treatment Works.
The report found that the "bacteriological quality of the surface water throughout this catchment is poor with high bacterial contamination indicating faecal contamination", showing an extraordinarily high 87%. This contamination is caused by overloaded sewers which lead to blockages and leaks. The problem is exacerbated by sewer infrastructural problems.
Adding to the problem is extensive paving in large housing complexes, which causes fast run-off into storm water drains, which are then overloaded, causing the rivers to flood and wash down pollution.
There are a number of bacteriological hotspots which have been problem for some time. Among the places they are found are Athol, Wynberg, Bez Valley, Zoo Lake and Bruma Lake. Several new hot spots - "new" defined as sites which have deteriorated in bacteriological water quality since the last test was taken - have been added to the list, including sites in Modderfontein, Little Falls, Ekurhuleni in Edenvale, and along Beyers Naude Road in Windsor.
The chemical quality of the water was also tested and found to be unacceptable at six sites. High ammonia levels in particular were found in the Sebenza Spruit, the Zoo outlet feeding Zoo Lake, the Kaalspruit, Bruma and in Bez Valley.
Effluent discharged from the six Wastewater Treatment Works is also tested. On one occasion, 28 January, the faecal count was found to be "slightly elevated" and has since been remedied.
Johannesburg Water (JW), the city's water and waste utility, has to comply with conditions laid down by the Department of Water Affairs and Forestry. When waste water is released into the rivers, it has a beneficial effect since "dilution of pollution" is achieved. On the negative side, the effluent adds to the phosphate level that eventually reaches the Hartebeespoort Dam.
Litter in the river systems was also found to be a problem, particularly at Bruma Lake. The litter tends to block the stormwater systems.
Klip River catchment
The bacteriological quality shows the presence of sewage in the water, with an unacceptable 67% of samples falling within the "unacceptable" and "bad" range.
Bacteriological hotspots include the upper reaches of the Harrington Spruit and the Natal Spruit, the Robinson Canal, the Russell Stream, and the tributary running through Protea and Moroka in Soweto.
Chemical tests show evidence of mining pollution, with chemical hotspots being the upper reaches of the Natal Spruit, the tributary in Davidsonville, Roodepoort and the Russell Stream.
There is a partial recovery of pollution of the Klipspruit and the Klip River due to the purifying effects of the extensive wetland areas, and the diluting effect of treated effluent from the nearby wastewater treatment works. The report stresses that these effects "should not be seen as a solution to the problem".
Bushkoppies and Goudkoppies Waste Water Treatment Works still need to come fully in line with national compliance levels.
Although littering was not so great a problem as with the Jukskei River in terms of water quality, it is an aesthetic problem; the litter is deposited on the river banks and remains trapped in the bankside vegetation.
Corrective action
Results of bacteriological pollution caused by sewage were forwarded to the Development Planning and Environment Directorate and then passed on to JW, which has taken corrective measures to deal with the problems.
JW has located and repaired blockages and overflows in a range of areas on both the Klip and Jukskei catchment areas.
Mine owners have been approached to reduce chemical pollution. Other industrial polluters are to be identified by Environmental Health officers and members of the public are encouraged to report polluters to these officers. On-site monitoring of industrial sites in Wynberg is being undertaken.
The Johannesburg Roads Agency has installed a system of nets at Bruma Lake, in an effort to trap litter before it enters the Lake. The Bruma Lake Owners' Association has employed a contractor to clean the surface of the Lake, and Pikitup will collect the bagged litter.
People taking samples on the Klip catchment are reporting cases of litter and illegal dumping to Pikitup.
Vigilant on-site inspections of sewer leaks and blockages will be undertaken in the industrial Wynberg area.
The removal of informal dense settlements has allowed access to leaking and broken sewer pipes, which have subsequently been repaired.
The pollution entering the Zoo Lake system is being investigated, with Water Quality Management, the Johannesburg Zoo and Environmental Health working together to solve the problem.
Field record sheets are now supplied to samplers, on which they record the water colour, odour, litter, flow, weather, and condition of river banks.
Bi-monthly water quality and sampling meetings have been initiated and chaired by Water Quality Management. All role players are encouraged to attend and participate.
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