Producing Safe Drinking Water: Ultra-filtration Membrane for the Removal of Indicator Bacteria

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1 Producing Safe Drinking Water: Ultra-filtration Membrane for the Removal of Indicator Bacteria

2 South African Vision To provide access to an adequate, safe and affordable supply of potable water to all people living in South Africa All people should be knowledgeable about healthy living practices and use water wisely Water supply should be sustainable and be provided by efficient and effective services providers who are accountable and responsive to the customers they serve

3 Prior 1994 Provision of Water Services An estimated % of South African population (14-18 M) without adequate water supply services Since 1994 South Africa has excellent advancements in the Water Sector Delivery of water services to an estimated 12 M of previously un-served households

4 Development of world class policies and legislation Ongoing expansion and upgrading of an extensive network of water infrastructure Compulsory national standards for the quality of the potable water provided are defined in SANS 241: Specification for Drinking Water

5 The South African National Water Act provides the foundation for water to be managed in an integrated manner based on the principles of equity, efficiency and sustainability. In terms of Constitution and the 1997 Water Service Act (Act 108 of 1997), Water Service Providers (WSPs): Responsible

6 Each Water Service Authority must: o implement a programme for monitoring the quality of drinking water provided to consumers o Ensure satisfaction of the Compulsory National Standards for Water (Gazette in June 2001) o Communicate immediately any threat to public health to the Department of Water Affairs and Forestry (DWAF) and to the Department of Health (DOH)

7 The regulations require that water supplied (by water service providers) which is intended for drinking or domestic purposes must be of a quality consistent with SANS 241 If the regulations relating to the compulsory national standards are contravened, the WSA will be held accountable

8 DWAF is the National Regulatory Authority o DWAF has the responsibility of ensuring that Water Services Institutions producing water for drinking and domestic purposes comply with the Compulsory National Standards Safe drinking water that complies with SANS 241 does not pose a significant risk to public health over a lifetime of consumption

9 Safe drinking water that complies with the SANS 241 is the norm in almost all South African metropolitan Areas Safe drinking water still a dream in rural areas High incidence of poor drinking water quality Poor service delivery

10 An estimated 5 million people in South Africa still have no access to treated drinking water within reasonable distances from their dwellings Many thousands more take water from water sources and use it untreated because of problems experienced with adequate and reliable potable water supply.

11 End user point - semi rural Dept of Environmental, Water and Earth Sciences

12 The Amazing World Of Microorganisms in the Water Domain: Imperatives for Sustainable Livelihood

13 National Profile» MIG Allocation o Lack of understanding by WSAs regarding the requirements for effective drinking water quality management o Inadequate management including monitoring of drinking water services o Inadequate asset management o Inadequate Water Service Authority institutional capacity (staffing, funding, expertise, education) o Lack of intervention to address poor drinking water quality when needed

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15 FRAMEWORK FOR A DIAGNOSTIC TOOL FOR TECHNICAL COMPLIANCE PROGRAM START TREATMENT PLANT MEASUREMENTS Design Aspects (from manual/measurements) Quality Control (final water) Process Control (unit processes) Plant Monitoring (sampling; analyses; record keeping; communication; statistics) Maintenance practices Risk Management NEXT COMPLIANCE MONITORING CYCLE Resample to confirm COMPARISON WITH STANDARDS (comparison of the plant measurements against standards and accepted norms) No problems identified REPORT COMPLIANCE IN ORDER TO DWAF (web etc)

16 Remeasure Problems identified REPORT COMPLIANCE NOT IN ORDER TO DWAF FLAG PROBLEM - AREAS Describe problems Mention implications / consequences Rank in priority order PROVIDE CORRECTIVE MEASURES AND PREVENTATIVE MEASURES Immediate and Longer Term Technical Management

17 ure FRAMEWORK FOR A DIAGNOSTIC TOOL FOR NON-TECHNICAL COMPLIANCE PROGRAM START AUDITS OF MANAGEMENT ISSUES AND HUMAN RESOURCES ISSUES Consider: Strategic Level Tactical Level (medium term planning) Operational Level (day-to-day) NEXT COMPLIANCE MONITORING CYCLE AUDIT OF MANAGEMENT PRACTICES Local and international management practices (Emanti/DWAF/AWWA) Draw up own criteria when none are available AUDIT OF HUMAN RESOURCES Number of personnel at the plant? Qualifications? Plant classification by DWAF Job conditions? (*) Motivational levels? (*) Inter-relationships? (*) Performance indicators?

18 Re-measure FINANCIAL Which financial systems in place? Are there sufficient funds for: operation? maintenance? overtime? Information sharing meetings? Procurement is it adequate? Transparency COMMUNICATION Which systems are in place? Emergency systems? Risk systems? SHEQ Safety, Health and Environmental Quality COMMUNITY INVOLVEMENT AND AWARENESS Refer to earlier studies undertakenh by NGO's, etc. Develop minimum requirements for assistance with compliance Customer care Trust of the public FLAG PROBLEM - AREAS and PROVIDE CORRECTIVE MEASURES REPORTING Immediate and Longer Term

19 Strategies to Ensure Sustainable Production of Safe Drinking Water in Water Supply Systems ECMA - Establishment of Catchment Management Agencies IWRM- Implementation of Integrated Water Resource Management

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21 Capillary Polysulphonate Ultra-Filtration (CPSUF) Membrane technology potentially offers the water industry a simple one or two-step treatment barrier to secure compliance with drinking water standards In South Africa, the Institute of Polymer Science, University of Stellenbosch, has developed low cost capillary membrane: CPSUF

22 Table 1.1: Summary of UCPSUF module characteristics Parameter Value Type of module Total length Hollow fibre, in/out operation, one permeate outlet, 8 bundled modules 1200 mm Max. feed pressure -48 Pa Hollow-fiber inner diameter 0.8mm Type of membrane Polysulphonate ph-range 4-9 Temperature-range ( C) Design performance 5-45 Pore size (µm) Feed water turbidity <20 NTU, permeate turbidity <0.2 NTU

23 UCPSUF system at the process evaluation facility, Wiggins Waterworks, Durban

24 The UCPSUF system has potential to produce high quality water that meets the standards required by South African guidelines in terms of bacterial indicator Current challenges for the system to be used in rural areas The cost of the membrane versus the quality of water it produces Increase of the operating cost of the system as due to the fouling of the membrane after use Membrane blockage in the worst situation where the membrane is operating in very high turbidity of greater than 100 NTU for extended periods Daily monitoring of the operating conditions ( pressure, flow rate, turbidity) Mechanical servicing (break down of the different parts of the membrane such as pumps, tubing pipes ) that needs to be done by experts. Lack of skills in rural areas

25 Conclusions Cost implication is one of the most crucial and controversial matters that seems to delay the implementation of UF system in rural areas A sustainable system must be cost effective Choices exist in terms of developing a low capital cost unit which will have high operating costs, or a higher capital cost unit, which will have lower operating costs The Conversely, the system could be highly automated (high capital) with low operator requirements (low operating costs)

26 Thank you Tshwane University of Technology, Faculty of Science Department of Environmental, Water and Earth Sciences Arcadia Campus, 175 Nelson Mandela Drive Republic of South Africa Tel W: +27(0) /6232 Fax: +27(0)