Restoring Blesbokspruit Wetland through bugs and home decoration | Infrastructure news

The Blesbokspruit Project (one of the five Blue Deal South Africa projects) works on restoring and optimising the health of the Blesbokspruit Wetland.

Located in the Upper Vaal catchment within the quaternary drainage area (C21D) near Springs, Ekurhuleni, the Blesbokspruit Wetland is along the Blesbokspruit River, one of the largest tributaries of the Vaal River in Gauteng. However, the Blesbokspruit Wetland has been under threat from acid mine drainage as well as poorly operated and maintained wastewater treatment plants, sewer reticulation and stormwater systems.

The Blesbokspruit Wetland was awarded the prestigious Ramsar status, but it has lost this due to the poor quality of water. The large quantities of water hyacinth and lack of reed management can cause flooding, while other fauna and flora have either died due to the depleted oxygen reserves and sunlight or have been unable to grow, as the hyacinth takes up all the space. Furthermore, water hyacinth loses a lot of water through its leaves, reducing water reserves in the wetland.

Improving the water quality within the Blesbokspruit Wetland will contribute to cleaner and properly managed water for the Vaal Water Catchment Management Area.

Stakeholders of the project

Interestingly, traditional healers have been most interested in rehabilitating Blesbokspruit Wetland, as they use some of the flora (that has largely disappeared) in Blesbokspruit to make medicines. “The involvement of the traditional healers in this project has been helpful, as they are community leaders and can win over the local community in working together to restore and preserve Blesbokspruit. We are working with them so that they can grow their herbs and plants in the area and by doing so, the local community will understand that any pollution will affect the plants and herbs that they use as medicine,” explains Mariska van Rijswijk, from the Dutch Water Authorities (DWA) and a team member of Blue Deal South Africa.

She adds that there is also a lot of enthusiasm from the many other stakeholders. “Blue Deal South Africa is unique in that we provide assistance as opposed to funding. We want to create systems that are independent and do not rely on the DWA. These projects (like the Blesbokspruit Project) need to be imbedded in the local government and local systems, so that when the project is finished, it is self-sustaining. Our focus is on water governance and knowledge exchange. We facilitate projects and make parties work together.”

The Blue Deal South Africa Programme has connected a multitude of private and public entities together in the Blesbokspruit Project, including: the Department of Water and Sanitation (DWS); the Gauteng Department of Agriculture and Rural Development (GDARD); Ekurhuleni Metropolitan Municipality; the Department of Forestry, Fisheries and the Environment (DFFE); the Centre for Biological Control (CBC) at Rhodes University; as well as traditional healers, community leaders and businesses.

Improving water quality

The Blesbokspruit Project is addressing the factors that impact the water quality and ecology on a practical scale, with key activities comprising:

  • Setting up a monitoring programme on water quality. Here, the DWS will start reviewing the existing monitoring programme, explore opportunities for extra real-time and/or innovative sensors, data software like Hydronet, and decide upon new monitoring locations with help of Dutch experts and other stakeholders.
  • Optimising the integrated management plan of the Blesbokspruit area by the GDARD, which will work with Dutch experts to optimise the existing plan on the themes of reed management and the water hyacinth. The goal of the management plan is to manage the reed and water hyacinth in such a way that is ecologically valuable, and the local community can reuse the harvested reeds and water hyacinth to craft innovative products.
  • Develop a business case on reed and water hyacinth management: GDARD and the DWS will develop a business case to make the management of reed and water hyacinth cheaper and more cost-efficient. It is envisaged that this can be done in a manner through which local communities can profit from these activities and thus community members will be trained to do the harvesting of reed and water hyacinth.
  • Allocate and use budget for additional sensors and probes: the DWS will allocate budget to buy extra sensors and probes to monitor the water quality.
  • Construction of a pilot bio-bed: Bio-beds are an innovative and natural technique to purify surface water using local materials and plants. The aim is to construct one or more bio-beds in and monitor its contribution to the water quality of the wetland.
Biological control – bugs to fight against water hyacinth

A free-floating South American weed that was introduced into South Africa in 1910, water hyacinth can produce hundreds of seeds per plant and remain viable for roughly 50 years. These seeds move between different water bodies, will lie dormant and then start to germinate when conditions are perfect (like nutrient-rich water). Without natural enemies, water hyacinth has spread throughout the Blesbokspruit Wetland.

A 2021 satellite image of the Blesbokspruit Wetland, where the green, fluorescent markings indicate the extent of the water hyacinth infestation.
Water hyacinth is thriving in South Africa due to the damming of freshwater systems and the creation of artificial lakes, slowing down water movement and producing a similar environment to the Amazon Basin, where the water hyacinth was originally found.

The CBC is using biological control to deal with the water hyacinth. Biological control – or the development of host-specific natural enemies – offers the most effective and long-term solution to many alien invasive plant species and insect pests. It aims to reunite invasive species with their natural enemies.

Residing at Rhodes University, the CBC has a particular interest in the development of biological control methods for invasive plants. The CBC focuses the majority of its research on understanding the ecological dynamics of invasive pests, aquatic and terrestrial weeds. It has been using Megamelus scutellaris (water hyacinth planthopper) as a means of biological control for water hyacinth at a number of sites, including the Blesbokspruit Wetland.

“These are small (3 mm long), sap-sucking insects that pierce the plant tissue, damaging cells. Damage in the petiole leads to water logging, which reduces plant buoyancy and causes the tissue to rot. This is evident once leaves start to turn brown, and sooty mould develops on the leaves,” explains Dr Rosali Smith, a postdoctoral fellow at the CBC who has been visiting Blesbokspruit since the end of 2020.

M. scutellaris is monophagous – it can only eat and develop on a target plant (in this case it is the water hyacinth). “We went through a vigorous, three-year process to bring these insects into South Africa. Two government departments (the Department of Agriculture, Land Reform and Rural Development and the DFFE) had to approve a permit that allows them to be imported into South Africa where they can be kept alive in a special quarantine facility that is built to specifications where insects cannot escape. Here, host-specificity testing is done (under strict guidelines) with a variety of plants to validate that the M. scutellaris is monophagous,” adds Smith.

M. scutellaris specimens are given a diet of plants to see if they will eat, survive and develop on them. Plants that are closely related to the target plant are selected. The CBC starts with species in the same genus, and then moves on to plants that are within the same family, and then in the same order. An extensive report is then written on the results and submitted to a scientific panel for review. Once the results are validated by the panel, and it is proven that the insect does not a pose a risk to South Africa’s indigenous fauna or flora, as well as agricultural produce, field testing can start.

There is an M. scutellaris rearing station set up at Blesbokspruit where the insects are then collected and released on to the water hyacinth. It takes time for the insect’s numbers to increase to a substantial number that is capable of causing visible plant damage. A few weeks after release, nymphs should be seen around the base of the plant and up the petioles (the bulbous stem). The population increases, and continues to feed off the sap of the water hyacinth until it eventually dies. They can also help reduce flowering; thus fewer seeds are introduced into the system.

The Megamelus scutellaris (water hyacinth planthopper) is used as a means means of biological control for water hyacinth at a number of sites, including the Blesbokspruit Wetland.
“There is no quick way to reduce water hyacinth at present and until the seed banks are depleted, which will take years, regrowth from the seedlings is to be expected every year. Water hyacinth will never completely disappear, but it can be kept below a level that is damaging. Biological control is the most effective and cost-efficient method of controlling invasive water weeds, as well as being entirely eco-friendly and sustainable,” states Smith.

The CBC was introduced to the Blue Deal Programme by a Gauteng biodiversity officer. “This is an example where a lot of people are working towards the same end goal, but no one communicates with each other. We were really interested in all of Blue Deal’s efforts to improve the water quality at Blesbokspruit and are really excited about the fact that Blue Deal brought everyone together. This is an excellent opportunity to bring expertise together. For instance, we don’t specialise in water quality but we do monitor it, as hyacinth thrives in nutrient-rich water. Getting rid of hyacinth is treating a symptom, not the problem. Therefore, using a water quality expert’s data will assist us,” maintains Smith.

She adds that the success of the project is dependent on everyone working together. “For instance, if the DWS sprays water hyacinth with a chemical spray, the M. scutellaris may die, or if water hyacinth is manually removed, the insects will be removed too. So there needs to be a lot of communication around how the water hyacinth project is tackled so that we do not waste resources. It is important to note that while biocontrol may take a longer time frame to work, it is often far more sustainable. But we can successfully use a variety of tactics if everyone works together.”

From water hyacinth to home decoration

Water hyacinth from Blesbokspruit is also being removed by the local community to make products that can be sold, such as woven baskets, rugs, office accessories, pet furniture and homeware. This improves the water quality while ensuring economic growth.

Tumi Mphahlele, a social entrepreneur, used the opportunity to contribute towards water conservation and uplift communities by creating these water hyacinth products under an entity called Thekga, which means ‘to support’ in Sepedi.

“Thekga is a collective of women on a mission to change the world, one drop of water at a time, through the eradication of alien invasive plants and the alleviation of poverty within the communities in which it operates,” explains Mphahlele.

The water hyacinth is harvested, the leaves and roots are cut and discarded, and the stems are sun-dried and then graded by size. They are then bundled, cleaned and stored for secondary processing. Secondary processing involves braiding in which the stems are spliced to create long bundles of rope.

A lot of research and development has gone into the development of these products. Hyacinth weaving is a novel technique in South Africa. After exploring modern methods, Mphahlele reverted to indigenous methods of weaving (looming) and coupled this with modern technology like steel fabricated frames for structure. The woven products are hand-braided and hand-loomed; however, hand tools are being procured to assist with primary processing in braiding.

“Once we have converted the stems into rope, we then use that rope as yarn to begin looming the baskets. Many hyacinths are needed to complete a basket. Each bundle contains 150 stems of water hyacinth. A small basket would typically use three bundles, with 450 stems of water hyacinth on average. We are also prototyping another briquette technology using the offcuts from the weaving as well as other alien invasive species such as wattle and sawmill waste,” explains Mphahlele.

“This is largely possible due to the encouragement from Dr Duncan Macfadyen, head of Oppenheimer Generations Research and Conservation, Debbie Muir from the Department of Environmental Affairs, as well Blue Deal South Africa to set my ideas in motion,” she explains.

Initially, Thekga was not allowed to harvest the hyacinth and create goods, as there was a focus on the total eradication of hyacinth and a fear that more hyacinth would be grown to create hyacinth products. But due to the long lifespan of hyacinth seeds (up to 20 years), South Africa will never eradicate the species. There is now a shift towards the management of hyacinth. By encouraging the manual removal of hyacinth from wetlands, Thekga is assisting with conservation as well as social development.

To date, 11 local women from the Blesbokspruit area have received formal entrepreneurial training on how to make products from water hyacinth. A team of creative freelancers comprising industrial designers and green architecture graduates is used for technical support.

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