Hout Bay Beach has a pollution problem, according to the City’s latest coastal water quality report.
The beach rated “poor” for the second year in a row in the “Know Your Coast” report.
Other popular beaches ranking in the “poor” category include Seaforth, Simon’s Town Long Beach, Clovelly, Sunrise, Monwabisi and the beaches in front of Muizenberg station and the Muizenberg pavilion.
Llandudno Beach, one of Cape Town’s Blue Flag beaches, was, however, ranked “excellent” up from “good” the year before.
The latest report covers coastal water quality from December 1, 2020 to November 30, 2021. It reflects the outcome of statistical analysis of 2 400 bacterial sample tests taken from 99 sites on the Atlantic and False Bay coastlines, twice a month in the surf zone and in tidal swimming pools, along a stretch of 307km coastline from Silwerboomstrand on the Atlantic to Kogel Bay on the east side of False Bay.
The samples are analysed by the City’s scientific services unit and categorised as “excellent”, “good”, “sufficient”, or “poor”, based on a 365-day rolling period.
For most healthy people, water quality that meets acceptable standards, “sufficient” or above, will pose little risk to their health, said the report.
Coastal water quality is assessed by comparing the number of E coli and enterococci bacteria in the water samples to limits set out in the South African Water Quality Guidelines for Coastal Marine Waters. The bacteria serve as indicators of faecal pollution and the potential presence of pathogenic micro-organisms.
The ratings are based on the estimated risk of gastrointestinal illness per exposure to swimming for 10 minutes with three head immersions. Less than 2.9% is “excellent”, less than 5% is “good”, less than 8.5% is “sufficient” and more than 8.5% is “poor”. Enterococci under 100 cfu/100 ml is “excellent”, under 200 is “good”, under 185 is “sufficient” and “poor”. E coli under 250 is “excellent”, and under 500 is “good”, “sufficient” and “poor”.
The water quality was “excellent” at Frank’s Beach, Miller’s Point, Simon’s Town Harbour and Kalk Bay rocks. Boulders Beach went from “sufficient” to “poor” to “excellent”, and Dalebrook tidal pool went from “excellent” in 2017 and 2018 to “sufficient” in 2019 and 2020 and “excellent” in 2021. Scarborough and Noordhoek south were rated “excellent”, while The Kom was “poor”.
Fish Hoek’s south beach rated “excellent” while the central beach yielded a “sufficient” result, up from “poor” in 2019 and 2020, according to the latest report.
Brian Youngblood, chairman of the Fish Hoek Valley Residents’ and Ratepayers’ Association, said coastal reports were meaningless due to the dilution factor. “Kids actually play in the stormwater run-off on our beach,” he said.
According to mayoral committee member for spatial planning and environment Eddie Andrews, this is the third “Know Your Coast” report issued by the City.
The report included the sampling results of the previous five years, from 2017 to 2021, which was pivotal in understanding the longer term trends in coastal water quality for Cape Town’s beaches, he said.
Apart from the annual “Know Your Coast” report, the City also publishes bi-weekly data updates on its website.
Mr Andrews said effluent from the City’s sewage-treatment plants had an impact on coastal water quality results in specific areas, but R3.3 billion in upgrades were already under way at the Zandvliet, Potsdam, Mitchell’s Plain, Macassar and Bellville plants.
Caroline Marx, from the Milnerton Ratepayers’ Association, said: “We are still waiting for the Urban Run-Off and Inland Water Bodies reports. These provide information on the stormwater culverts leading to our beaches. They alert us to sewage overflows, such as sewage pump stations failing to restart after load shedding events and their alarm systems failing.”
Earlier this year, Ms Marx and others were appointed to the mayor’s Water Quality in Wetlands and Waterways Advisory Committee, which was established to improve communication between City officials, councillors, experts and activists and seek solutions to water-related problems.