Spraying of Vaal’s water salad started
Rand Water this week in a post on Facebook confirmed that an integrated approach, including physical removal, biocontrol, and chemical application will be followed in managing the water salad and hyacinth crisis on the Vaal River.
Spraying of the herbicide Glyphosate on the water lettuce and hyacinth, done by professional crop sprayers and drone operators, started on Tuesday 13 February.
Rand Water stated that the application of all herbicides used on the project has been approved by both the Department of Forestry, Fisheries and the Environment, and the Department of Water and Sanitation South Africa “and they are set at a sub-lethal dose because we are implementing an integrated approach”.
According to Rand Water the sub-lethal dose increases the sugar and carbohydrate contents of the Pontederia crassipes plant making it more palatable for the biocontrol agent. “The specific formulations of the glyphosate that were recommended are made based on expert opinion and research, and field work is being monitored for compliance at present.”
Photo credit: Vaal River Rats South Africa Facebook Page.
“Although biocontrol agents are already on the Vaal Barrage, additional biocontrol agents will be released on 15 February (should weather conditions permit it). They will hopefully be released in the upper reaches of various water bodies (stream inlets) on the Barrage as well as in some selected areas between reed beds on the Barrage, Rand Water concluded.
Meanwhile concern has been expressed with regard to the spraying of Glyphosate by among others the organisation WaterCAN and prof Anthony Turton.
Prof Turton said that as the Vaal River crisis escalates at an exponential rate, the lack of coherent government policy is increasingly driving irrational “solutions”. “This aerial assault is oblivious to the cause of the problem – dysfunctional sewage works run by many different municipalities collectively discharging untreated effluent into tributaries of the Vaal – so it seeks to remedy a symptom by adding more chemicals to a system already overburdened with a cocktail of chemicals and increasingly drug resistant pathogens,” prof Turton said.
He added that glyphosate, is known as a controversial substance with an international history of ‘public pushback’.
He questioned whether a root cause analysis has been performed by a competent team of independent professionals, and whether there is a coherent rehabilitation plan.
