7. EVALUATING THE APPLICATION OF THE STUDY IN WATER RESOURCE MANAGEMENT
7.3 APPLICATION TO WATER RESOURCE MANAGEMENT IN SOUTH AFRICA
7.3.2 Aligning with South African Policy
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The laboratory at the Unilever Centre for Environmental Water Quality, Institute for Water Research is the only laboratory undertaking toxicity tests in the Eastern Cape. This highlights the lack of capacity and laboratory facilities to undertake toxicity testing in South Africa and further highlights the importance of the role that this laboratory plays in advancing micro- algal toxicity testing in South Africa. Not only does this laboratory have an established culture of the standard toxicity test species P. subcapitata, there are culturing facilities and capacity to maintain indigenous cultures as well. The addition of indigenous species in a suite of species for routine toxicity testing will not only advance research but will also be a practical applicable addition to water resource management.
Another further challenge to be recognised is the difficulty associated with establishing and maintaining micro-algal cultures (Griffin et al. 2011). This task is labour intensive but very necessary. The international trend is towards the use of battery of species in micro-algal toxicity testing and South Africa needs to adopt this if this country wants to be aligned with the rest of the world. This study has provided the ground work in terms of identifying the species that would be useful toxicity test species. The locally isolated species identified in this study are easy to isolate and maintain in culture. Chlorella sorokiniana is a particularly sensitive species while C. vulgaris has the advantage of being a true cosmopolitan species that is found in freshwater environments around the world. Chlorella vulgaris has also been recommended by some countries as a toxicity test species in addition to P. subcapitata, and doing the same in South Africa would be a great contribution to routine toxicity testing in South Africa, especially with now that it is known for certain that this species is available in our own freshwaters.
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Act (Act N0. 36 of 1998) is the main South African legislation that incorporated water resource protection into policy. The relationship between the NEMA and the NWA is implied in the land-based activities such as mining that have water related impacts such as effluent discharge. Controlling the impacts of such activities on the country’s water resources is a requirement of the NEMA and the NWA. Chapter 6 of this study draws attention to the contribution that micro-algal toxicity testing can have in this regard. Micro-algal toxicity tests maybe appropriate and useful in assessing and regulating effluent discharges to natural aquatic systems as they are able to respond with stimulation, inhibition or both, thereby reflecting synergistic or antagonistic effects that the components of these effluents.
The NWA forms the basis of managing water resources through balancing protection and use and ensuring that water resources are developed, conserved and controlled in a sustainable and equitable manner for the benefit of all persons. The two approaches that balance water resource protection and use according to the NWA are referred to as ‘resource directed measures’ (Chapter 3) and ‘source directed controls’ (Chapter 4) respectively. Resource directed measures provide descriptive and quantitative goals for the state and condition of the resource and are geared towards the protection of water resources, while source directed controls specify the criteria for controlling impacts such as waste discharge and abstraction licences thus focusing on the use of the country’s water resources.
The NWA recognises three resource directed measures: water resource Classification, the Reserve and Resource Quality Objectives. These three measures form the basis of protecting South Africa’s water resources according to Chapter 3 of the NWA. In recent years micro- algae have been used as one of water quality assessment tools in resource directed measures in South Africa. Diatoms and periphyton (green-algae) are now a major part of water quality monitoring in Reserve and Resource Quality Objective determinations. Incorporating of toxicity testing in source directed controls as one of the conditions in wastewater and industrial discharge water licences would advance water resource management in South Africa. The addition of micro-algae as one of the recommended toxicity test organisms in this regard would be a significant contribution as they play an important role in aquatic ecosystems as the base of the aquatic food chain.
Mining and mineral processing are major land-use activity as well as contributors to the South African economy. A number of mining and mineral processing activities either require
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Environmental Impact Assessments to be conducted in terms of NEMA or constitute water use requiring a licence in terms of the NWA. The Minerals and Petroleum Resources Development Act (Act No. 28 of 2002) is linked to NEMA in that it makes provision for environmental planning and management (Chapter 4, Sections 37-39) in activities associated with mining, mineral processing and fuel production. Some of the water related activities associated with the aforementioned processes are included in the broad definition of water use as stated in the NWA (Chapter 4, Section 21). Monitoring programmes and tools such as the DEEEP and the NTMP that include micro-algal toxicity testing when fully implemented could be instrumental in ensuring compliance of mines with the set effluent discharge standards and toxicity limits, in order to protect the country’s aquatic resources.
As one of the major land-use practices in South Africa, agriculture impacts on the management of the country’s water resources. The quality of some water resources in South Africa is deteriorating due to agricultural return flows, as well as pesticide spray-drift and surface run-off. According to the Pesticide Management Policy (Gazette No. 33899, December 2010) there need to be restrictions on users to limit the movement of harmful pesticides to water resources, under the Fertilizers, Farm Feeds, Agricultural Remedies and Stock Remedies Act (Act No. 36 Of 1947). The Conservation of Agricultural Resources Act (Act No. 43 of 1983) makes provision for control over the utilisation of the country’s natural agricultural resources in order to promote conservation of the soil, water resources and vegetation, and to combat weeds and invader plants. Invasive plants do not only threaten the country’s biological biodiversity, but also water security and the ecological functioning of aquatic ecosystems. Working for Water, a programme administered by the Department of Water Affairs and Sanitation is at the forefront of the fight against invasive alien species.
Chapter 6 of this study includes toxicity tests with Roundup, one of the pesticides used to combat invasive plants in South Africa, and assessing the effects of these pesticides to non- target organisms such as algae in the country’s waters is an important contribution of this study to water resource management. Water quality guidelines for Roundup have recently been developed and this study (Chapter 6) has contributed to the toxicity data that was used to determine those guidelines.
Eutrophication is one of the significant water quality issues in South Africa (NWRS 2013), particularly in catchments where agriculture and mining are prevalent. This issue is exacerbated by the poor performance of some of the wastewater treatment works in the
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country. Some of the wastewater treatment works lack proper maintenance and management of the infrastructure and processes, resulting in poor treatment and high nutrient loads in the discharged effluent. As shown in Chapters 5 and 6 of this study, understanding the contribution of the stimulatory effects of salts and effluents to micro-algae to the problem of eutrophication could be the key to controlling the problem in the country. Including micro- algal toxicity testing in monitoring programmes such as the National Eutrophication Monitoring Programme (NEMP) would be major step forward in dealing with eutrophication.
This study has shown stimulatory effects of effluents on micro-algae, although this requires further investigation, it could be a starting point and a justification for including micro-algal toxicity testing (particularly with indigenous micro-algae) in eutrophication monitoring for water resource management.