There have been at least two big sewage spills into the Silvermine River Estuary in the space of four months
The City of Cape Town has blamed load shedding for causing sewage pump stations to fail, leading to sewage overflowing into stormwater drains and from there into the estuary.
Last month, one confirmed spill and one unconfirmed smaller spill followed an earlier spill in December (“Estuary flushed after sewage spill,” December 20, 2018).
Clovelly resident Ina Streicher accused the City of allowing the estuary at Clovelly to become a sewer pit.
She said she had been walking to Clovelly beach on Sunday March 3 when she had noticed the state of the estuary.
“What a total shock. All the birds are gone (can’t blame them). There is still evidence that raw sewage is floating, plastic is dumped in the estuary between the railway bridge and motor bridge. Vagrants living under the bridge are messing the place up and nobody says a word,” she said. “When the rain comes all that mess will end up in/ on our beautiful beach.”
Evanne Rothwell, of Fish Hoek, said she had noticed a big spill on Wednesday March 20.
According to her, she reported it the next day and got a reference number, but it continued for another five days before the municipality did anything about
it.
“By now faecal matter had been observed in the wetlands and we have probably lost most, if not all, our aquatic life, as little could survive a spill like this,” Ms Rothwell said in a letter to the False Bay Echo.
“It is an ecological disaster and an indictment on the City that a biodiversity area could be ignored to this extent. From what I saw, biological enzymes were only applied on Monday March 25 to try to mitigate the effects of five days’ solid flow,” she said.
The wetlands are a breeding ground for the endangered western leopard toad, and Ms
Rothwell said it was unclear what impact the spill would have on the estuary’s aquatic life, but she feared it would be “devastating” and would have a knock-on effect on bird life and other creatures relying on the wetlands for their habitat.
But mayoral committee member for community services and health, Zahid Badroodien, said the recreation and parks department had found no “observable effect” on the aquatic diversity and bird life. And any impact on the toads would be “negligible”, he said, because they only used the wetland to breed between July and December and the rest of the
time they lived in gardens more than 2km away. They were un-
likely to suffer if the wetland was “flushed” before the next breeding season.
He said there had been an increase in algae in the middle pond, which was being closely monitored. “Since the spill was primarily contained to the upper two ponds, the bird life in the lower sections of the wetland appear to be unaffected by the spill. It is likely that they will move to a more habitable site, in the event that the environmental conditions no longer become conducive,” he said.
The department was continuously reviewing the ecological impact of sewage spills on the wetland, he said.
“It will, however, take some time to determine whether any long-term damage has been sustained,” he said.
Mayoral committee member for water and waste, Xanthea Limberg, said Eskom’s load shedding damaged the City’s expensive infrastructure, which was not designed to be switched on and off.
But why had it taken five days, according to Ms Rothwell, to act?
Ms Limberg failed to answer that question, saying only that the spill had been dealt with “in a reasonably quick time”. The overflow had been traced through the stormwater system, she said.
Ms Limberg said the spill on March 20 was not the same blockage area as the one in December 2018, although the sewage had ended up in the same stormwater system leading to the estuary.
The estuary area had been dosed with bio-enzymes after clearing the blockage, she said.
“The City’s water services department will be checking this overflow system to distinguish how it operates and whether it can be closed off. This will assist in lessening
the volume of any possible future spills that may occur without any other detrimental effects,” she
said.
