The dredging of Zeekoevlei will start in June this year. That’s according to the City’s Spatial Planning and Environment Directorate. The City’s Deputy Mayor and Mayoral Committee Member for Spatial Planning and Environment, Eddie Andrews says the project team is making great progress with the preparations for this major operation that will take about 2 years. It forms part of the City’s plans to improve water quality.

MMC Andrews says, “The last time the City undertook a dredging project was in 1983 when parts of Home Bay were dredged.”

Zeekoevlei dredging to commence in June

Andrews says Zeekoevlei is located in the False Bay Nature Reserve and is a Ramsar site of international importance for wetlands. He says the City is accredited as a Ramsar City. Andrews added that improving water quality is a key international commitment, which is aligned to the Mayoral Priority Programme (MPP): Sanitation and Inland Water Quality MPP.

MMC Andrews added, “The current dredging is more extensive and a significant milestone event,’ said Alderman Andrews.

The City says 2 sections of Zeekoevlei will be dredged: first Storm Bay, and thereafter the contractor will move to the section known as Home Bay.

Two sections of Zeekoevlei will be dredged

MMC Andrews says the dredged material will be pumped with a slurry pipeline from Zeekoevlei to dewatering ponds where the sediment can dry out. He added that over the past decades, there has been a significant build-up of sediment and nutrient-rich organics in the Zeekoevlei lakebed that has resulted in algal blooms, which have been impacting the overall health of the vlei and its water quality for recreational users.

Dredging information

• Two sections of Zeekoevlei will be dredged over 26 months, namely Home Bay and Storm Bay
• The total volume of sediment to be dredged from Home Bay is 157,000 m³ and is estimated to take about 14 months
• The total volume of sediment to be dredged from Storm Bay is 207,000 m³ and is estimated to take about 12 months
• Hydrographic surveys of the dredged area will be conducted every two weeks to measure the progress
• The dredged sediment will be pumped from Zeekoevlei via a 4,3km long slurry pipeline to ponds for dewatering and storage
• The slurry pipeline will cross several roads within the area, amongst which Governors Walk and Peninsula Road
• The supernatant water will be pumped from the dewatering ponds to the Cape Flats WWTWs via a 2,3km long pipeline
• The contractor will be constructing rubble mound bund walls at the dewatering ponds to assist with the dewatering and drying of the dredged sediment
• Dewatering sumps will be constructed around the perimeter of the dewatering ponds to assist with the drainage of supernatant water to the Cape Flats WWTWs
• The contractor also needs to upgrade the access roads within the Cape Flats WWTWs area for the transportation of dredged sediment