The volume of the water lettuce and water hyacinth across the Vaal River Barrage Reservoir has reduced markedly over the past few months as removal efforts continue.

According to a Rand Water statement, water lettuce and hyacinth coverage shrunk from 395 ha in April to 100 ha currently.

While water lettuce emerged in the Vaal river as far back as 2021, flooding in 2021 and 2022 discouraged the aquatic invasive species from settling. However, with lower rainfall in the summer of 2023 and continued high levels of nutrients in the river, mainly from sewerage, the aquatic weed grew exponentially and out of control.

The reduction in the invasive plant species is the culmination of a close working relationship since early this year among the Vaal River community, Rand Water, the Department of Water and Sanitation (DWS), Rhodes University’s Centre for Biological Control, AfriForum, Omnia and Save the Vaal Environment.

The community, collaborating with Rand Water and various authorities, using their own resources and spending about R10-million over six months on the Vaal Barrage reservoir, assisted in removing the alien invasive species.

Federated Hospitality Association of South Africa national chairperson Rosemary Anderson said the “unsung heroes” tirelessly and generously provided the funds, significant resources and time to lead the way.

“Without them, we would not be winning the invasive aquatic weed war.”

“We are also most appreciative to Omnia, which donated funds for the removal of over 7 km of aquatic alien invasive weed from the Taaibos,” added Rand Water corporate services GM Mbuyiswa Makhubela.

The DWS appointed Rand Water as the official implementing agent for 3 years to control and eradicate the alien invasive weeds in the Vaal River Barrage reservoir, and the water utility is continuing its implementation of the control plan under the authorisations issued by the DWS and the Department of Forestry, Fisheries and the Environment (DFFE).

This includes an integrated approach of physical extraction, curtaining, biocontrol and the use of herbicide to halt the out-of-control growth.

“The significant contribution of the Vaal Barrage reservoir community and positive approach in working closely with all parties definitely needs to be acknowledged and applauded. I look forward to continuing this positive working relationship going forward, with government taking appropriate accountability by committing significant resources to enable sustained control over these alien invasive aquatic weeds and improvement of water quality that will ensure communities livelihoods are not threatened again,” said DWS water use compliance chief director Anet Muir.

Rhodes University Centre for Biological Control’s professor Julie Coetzee and Dr Kelby English assisted with various aspects such as mapping, biocontrol agents and a range of technical support to assist with introducing weevils and hoppers to assist in controlling these invasive alien plants.

With Rand Water’s recently awarded order for the physical removal of 60 ha of alien invasive plants, Omnia’s contribution and the communities' own continued self-funded efforts, there should be little to no more aquatic weed in the Vaal River Barrage by the end of July.

“This has definitely been a group success story, where working closely with all parties and meeting regularly between all of us, has resulted in the success we see today. We have not won the war yet since we are not sure what this coming summer will bring, but we are in a far better position to be ahead of the game and control the alien invasive aquatic weed narrative than we were before,” said Rand Water’s Dr Leslie Hoy.

The DWS, in collaboration with the DFFE, is also focused on the water quality and pollution of this critical water resource, in addition to the invasive species.

Former Water and Sanitation Minister Senzo Mchunu, during an April 2024 workshop with municipalities in the catchment, announced the establishment of an anti-pollution forum for the Vaal catchment and approved the chairperson, with work set to start in July.

The department is also finalising its criteria for the publication of a polluters list while continuing with the enforcement action against transgression polluters, including municipal wastewater treatment works.