Bulk scale industrial effluent reuse potential in South Africa

Abstract

Rationale: Water scarcity, increased pollution, unprecedented population growth and climate change are collectively driving the need to reuse water with the aim to enhance water security, sustainability, and resilience. It is clear that South Africa’s already strained water resources will become even more stressed in the near future. The Department of Water and Sanitation predicted that by 2030 water demand will reach 17.7 billion m3, far more than what is available to allocate. Globally, responsible and efficient water management is fast becoming a pressing reality for domestic users, agriculture and industry alike. The challenge is therefore to capitalise on the limited water we currently have. Solution: Bulk-scale reuse of industrial water effluent can play a significant role in water security in a water scarce country, such as South Africa, as it can augment or partially substitute freshwater resources needed for domestic purposes and future development. Water reuse in South Africa is however lagging. Approach: An Atlas for potential industrial bulk scale water reuse was produced from publicly available Natsurv and WARMS data. It highlights the urgent need for water reuse to form an integral part of an integrated water management supply approach in South Africa. While South Africa has progressive legislation to support the implementation of wastewater reuse, it can also be regarded as a barrier in implementing reuse projects, as often water reuse standards and guidelines are far too stringent to allow for cost-effective reuse options to be developed and implemented. Findings: Currently, very little to no data exists regarding wastewater reuse options, treatment options and capabilities, or costs, which can be used for decision making, and much more directed research and information is needed in order to identify wastewater and industrial effluent volume availability, quality and fitness for use in South Africa. A web-based Decision Support System (DSS) tool is being developed to enable municipal and industry partners, and water quality managers to make informed decisions for possible reuse options. The tool aims to directly assist by linking industrial effluent volumes and quality to fitness for use, and linking it with specific industries in the geographical vicinity based on industry specific water quality and quantity requirements. The DSS can be particularly useful in wastewater reuse as it can provide assistance in the evaluation and selection of alternatives for a given reuse application. In addition, the tool will enable engineers and industry partners to collaborate to identify and employ treatment technologies and capabilities to link industrial effluent quality and volumes available to that of potential user requirements in a geographical area.