At least 32 million liters of untreated sewage is pumped into Cape Town's marine reserve every day through the Greenpoint, Sea Point and Hout Bay outfalls.
A new feasibility study suggests it would cost up to R8 billion to either build a wastewater treatment plant to treat the wastewater in the first place or pump it into an existing sewage plant.
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Cape Town has been pumping sewage into the sea from its Atlantic coast for decades, but the practice has faced increased scrutiny and public opposition since photos of sewage floating along the ocean surface were published in 2016. .
Marine outlets have come under renewed public scrutiny over the past year, after Forestry, Fisheries and Environment Minister Barbara Creasy ordered the city to begin a public engagement process regarding the required release permits for the outlets. It's increasing.
Read: Cape Town orders public hearing on sewage pumped into sea
The public participation process ended Nov. 21 with 1,979 comments submitted, according to a presentation by Zutari, the consulting firm that managed the city's process.
Mr Zutari also announced early last year that sewage from Greenpoint (including all sewage from the city center to Salt River), Camps Bay and Hout Bay would be released into the outfall. was commissioned to determine the feasibility of processing beforehand.
The study was presented at a workshop on January 31 attended by the city's Water and Sanitation Directorate, the Water and Sanitation Portfolio Committee and the Mayor's Advisory Committee on Inland Water Quality.
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A presentation provided to GroundUp on Friday said upgrading the marine water pumping station and current infrastructure would cost R100 million in the short term.
Zutari pointed out that the Hout Bay Outlet does not comply with the Coastal Water Discharge Permit issued by the Department of Forestry, Fisheries and Environment (DFFE) in terms of total Kjeldahl nitrogen (a measurement of organic and ammonia nitrogen in sewage). did. The probability of meeting the requirements was only 41%.
It was also reported that the outlet of Hout Bay did not meet permit conditions such as maximum discharge volume.
READ: Marine sewage: City fails to meet Hout Bay permit conditions
When it comes to releasing heavy metals into the marine environment, the Green Point Outlet met only 34% of the zinc level requirement, while the Camps Bay Outlet had an overall compliance rate of 46%. However, since 2020, overall compliance has improved.
As designated marine discharge outlets, all three are exempt from measurements of fecal bacteria (such as E. coli and enterococci) and chemical components.
solution
This research provides medium- to long-term solutions for treating sewage discharged from ocean outlets.
In the medium term, this study presents the option of simply extending the existing ocean discharge pipeline. The pipeline is currently between 1.35km and 2.1km long, but in the case of Camps Bay and Hout Bay, the actual discharge is only about 700 meters from land. This is due to the shape of the bay.
Without providing treatment options, extending the pipeline by 10km at Camps Bay, 15.3km at Greenpoint and 11.6km at Hout Bay would result in: It will cost between R2.2 billion and R2.6 billion. It's buried underneath.
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Building new sewage treatment facilities in Greenpoint, Camps Bay and Hout Bay will cost between R2.2 billion and R3.4 billion, depending on the extent of treatment.
The long-term scenario presents the option of pumping sewage from all three regions to various existing sewage treatment facilities via new marine or land-based sewage pipelines.
The wastewater treatment facilities being considered are Potsdam (Milnerton), Cape Flats (Strandfontein), Athlone, and Vildevowerlei (Komeje). To cope with increased sewage flows, additional facilities must be built at these wastewater treatment facilities.
These options range in price from R2.2 billion to R7.3 billion, with onshore piping options generally being cheaper than offshore pipelines.
Report is in final stages
In a media statement issued on Thursday, Mayco's member for water and sanitation, Zahid Badroudien, said that in light of comments received during the spill permit's public participation process, a more detailed report will be published. He said that a final decision is being made.
“Preliminary insights reveal that treatment quality is rated as the biggest concern…the main reason for opposing marine outlet discharge permits, and that sentiment is based on three The same was expressed at all outlets,” Badrudeen said.
He said the city is busy compiling Creasey's public engagement report, scheduled for Feb. 29.
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“In the immediate future, short-term solutions will be considered, focusing on replacing and refurbishing existing treatment facilities and drainage infrastructure. Additionally, addressing maintenance gaps and extending the life of the infrastructure will be considered. You can also.”
He said it was agreed that an environmental impact assessment would need to be carried out as part of considering the proposed options, as well as assessing the impact on the city's budget.
The viability of the options would need to be assessed and “if found to be viable” funding would come from a long-term infrastructure programme.
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© 2024 GroundUp. This article was originally published here.
