A local, Patric Tariq Mellet, took this photo of Rietvlei recently after noticing water crossing the fence and ditch along the R27 highway. The waterbody had to be closed numerous times in the past due to a highly toxic blue-green algal bloom found in the water. In June 2020 a large spill occurred – high levels of E. coli were recorded resulting in the closure of the vlei to all water activities.
- Recent water sampling at Rietvlei revealed dangerously high levels of E. coli, raising public health concerns.
- Officials have requested urgent resampling and warned the public to exercise caution when using the waterbody.
- The City continues to investigate the source of contamination and is working to address the issue.
Alarming signs of contamination emerged from the latest water sampling at the Rietvlei waterbody last week (10 September), revealing dangerously high levels of E. coli.
Two key sampling points recorded readings over 4 000 per 100ml, far exceeding the safety threshold and raising urgent concerns for public health and the local ecosystem.
Louis van Wyk, reserve supervisor for the Table Bay Nature Reserve, said in an email last week that intermediate recreational contact with water can be expected to carry an increasing risk of gastrointestinal illness as faecal coliform levels increase.
“We have requested urgent resampling today (last week) and will update stakeholders as soon as possible with regards to the outcome. However, we urge water users to exercise caution when utilising Rietvlei’s recreational waterbody, especially in the vicinity of the Bayside canal outlet. We are engaging with relevant departments to trace and stop the cause/source of the contamination,”
Van Wyk said.
On Tuesday, 17 September, TygerBurger was still waiting for comment from the City and the cause of the contamination.
Background
TygerBurger previously reported (“Rietvlei woes continue: Water sport athletes demand City fix ‘mess’,” 1 March 2023) of several past pollution spills at Rietvlei waterbody. The waterbody had to be closed numerous times due to a highly toxic blue-green algal bloom found in the water. In June 2020 a large spill occurred – high levels of E. coli were recorded resulting in the closure of the vlei to all water activities.
This was due to the ingress of sewage water into the stormwater system, leaks, failed equipment, load shedding, and a total lack of the City’s engagement and accountability, environmentalists said at the time. However, the City has since launched “Otter”, the new weed harvester at Rietvlei waterbody in May, to help curb green algal bloom in the water. Otter’s job is to remove water weeds like hyacinth and water lettuce from waterbodies in an environmentally responsible manner.
READ | Rietvlei woes continue: Water sport athletes demand City fix ‘mess’
A weed harvester is a specialised vessel with blades underneath for the cutting of weeds. It is equipped to cut, gather, and remove weeds to improve water quality and assist recreational users. However, some algae are critical to the functioning of the vlei, thus, it is important to also keep these areas where weed is not harvested.
The Milnerton Aquatic Club (Mac) previously told TygerBurger the build-up of nutrients in Rietvlei is a direct result of pollution-related incidents over the past few years.
Bayside Canal upgrade
The City said the Bayside Canal, an R87,5 million upgrade which is curently onging, is set to improve Rietvlei’s water quality.
This comes after City investigations showed reed growth in the canal hindered flow which caused the past flooding incidents at the Bayside Mall.
As a result of development within the catchment area, the need to upgrade the Bayside Canal will cater for increased stormwater flow during peak periods. Upgrades to the canal will also address the major challenges where litter and pollution from various stormwater channels end up in the Rietvlei.
READ | Introducing Otter: Eco-friendly weed harvester at Rietvlei
Mayco member for water and sanitation, Zahid Badroodien, said he is optimistic about the promising progress being made on the upgrade of the Bayside Canal, from Blaauwberg Road to Rietvlei in Table View, which began in November last year.
The aim of this upgrade is threefold: to increase the capacity of the Bayside canal; to provide naturally-structured treatment facilities which improve the quality of stormwater run-off that flows from the canal into the Rietvlei, and to provide adequate access for systematic maintenance in the future.
This is one of the City’s major river and waterways infrastructure upgrade projects currently underway, which forms part of the R131 million investment into projects of this nature in the 2023-’24 financial year.
The City has started the upgrade of the canal with the removal of reeds and the widening of the current canal.