By Niemah Davids
Rapid urbanisation, an increase in the number of informal settlements and ageing infrastructure are to blame for the "badly polluted" 14 rivers and 10 wetlands around the Cape Metropole.
And the City of Cape Town has warned residents in at least six suburbs to stay clear of the rivers and vleis in their areas.
This comes after scientists detected increasing counts of E coli and faecal coliform bacteria in rivers and wetlands.
Speaking to the Cape Argus, Clive Justus, mayoral committee member for utility services, said the poor water quality was the result of an increasing number of informal settlements, rapid urbanisation and ageing infrastructure.
In the past eight years, the average conformity with acceptable standards of inland water resources for recreational use had dropped from 80 percent to 58 percent, Justus said.
He urged residents near wetlands including Lotus River, Kuils River, Eerste River, Milnerton Lagoon, Zeekoevlei and Princessvlei to exercise caution and avoid coming into close contact with the contaminated water.
"These are but a few of the rivers I have mentioned. Residents are warned to beware."
He warned that the water was not suitable for human consumption and that open wounds should not be allowed to come into contact with the water.
Justus said that while the reasons for the polluted water varied, the main reason was the increase in informal settlements in the city.
"Have a look at the Lotus River there's a number of informal settlements surrounding it, as well as the Kuils River, (which) runs past the Khayelitsha informal settlement.
"Here they don't have proper sewerage and this is possibly the biggest contributing factor," he said.
Justus said Cape Town's population had increased from 800 000 to 3,4-million in the past 50 years, but infrastructure investment had not kept pace with this growth.
"Our infrastructure is now under great strain, so we have to move fast to catch up with the backlogs and get ahead of the curve."
He said the country's electricity crisis and ageing infrastructure had also proved to be among the key reasons for the deterioration of the water's quality.
"With the electricity crisis, pumps are switched off and on a lot. This way they become ineffective.
"And with the infrastructure, we have undersized capacity. These pumps were designed to cope with a certain amount of sewage; now suddenly this amount doubles and pipes can't deal with it.
"Our infrastructure is under great strain," he said.
Justus said R280-million had been set aside during this financial year to upgrade Cape Town's wastewater treatment plants. This was expected to improve the quality of treated water entering vleis, rivers and the sea.
The city is building a new wastewater treatment plant at Fisantekraal, north of Durbanville, and upgrading existing facilities at Potsdam, Athlone, Zandvliet, Bellville, Scottsdene and Westfleur to provide adequate treatment capacity.
"We are working with a plan," he said.
"This is not pie in the sky. (But) there is no quick fix solution and we realise that the water quality will only improve significantly once the infrastructure backlog is eliminated," Justus said.