Decision Making Support in Wastewater Management: Comparative analysis of techniques and tools used in centralized and decentralized system layouts UDK 628.2


  • Harmony Musiyarira Polytechnic of Namibia, Windhoek, Namibia
  • Cornelius Chris Reynders University of the Witwatersrand, Johannesburg, South Africa
  • Prvoslav Marjanovic Educons University, SremskaKamenica, Serbia



centralized systems, decentralized systems, decision support systems, multi criteria decision analysis, sustainability


             Wastewater management has been seen primarily as a technical and economic issue but it is now recognised that these are some of the elements in an array of other factors that affect sustainability of wastewater systems. Literature studies point out that municipal authorities have a general and long-standing tradition of using indicators in monitoring performance, reviewing progress and reporting the state of the environment as part of the regulatory enacted compliance. However, they have neglected other critical aspects of use of these indicators such as their input into the planning and decision making process. This research advocates for the use of sustainable indicators in a context based planning approach and the utilisation of Multi Criteria Decision Aid (MCDA) in a two step approach for comparative analysis and assessment of the sustainability of wastewater systems. The overall objective was to develop a methodology for wastewater systems selection and to produce a practical planning tool to aid in decision making for municipalities. Another objective was to provide recommendations for wastewater and sanitation management improvement in the case study area. The methodology consisted of comprehensive literature review, case study analysis, a review of the Decision Support Systems (DSS) in use and the development of the DSS for Gauteng Province. The full spectrum of viable wastewater or sanitation options was incorporated into the DSS. From the sustainability assessments carried out using Multi criteria decision analysis, one result showed that varying degrees of sustainability are obtainable with each treatment technology involved and decentralised technologies appear more sustainable. Based on the local context and indicators used in this research, the DSS results suggest that land treatment systems, stabilisation ponds and ecological treatment methods are more sustainable. One major finding from literature is that no technology is inherently sustainable on its own but is a function of the local context specifics. Since there is so much variation in social and economic needs within the areas; the overall results imply that a differential wastewater management approach should be employed with tailor made solutions resulting for each municipality or certain areas within a municipality.


Adewumi, R.J., Ilemobade, A.A & van Zyl, 1. J. E. (2010). Decision support for the planning of integrated wastewater reuse projects in South Africa. IWA Publishing.Water & Science Technology: Water Supply-WSTW (10) (2) 2010.

Agudelo, C., Mels, A. and Braadbaart, O. (2007) Multi-criteria framework for the selection of urban sanitation, 2nd SWITCH Scientific Meeting, Dan Panorama Hotel, Tel-Aviv, Israel. 25 - 29 November 2007

Ahmed, S. A., Tewfik, S. R. &Talaat, H. A. (2002). Development and verification of a decision support system for the selection of optimum water reuse schemes, Desalination, (152): 339-352.

Balkema, A.J., Preisig, H.A, Otterpohl, R., Lambert, F.J.D. &Weijers, S. (2001). Developing a model-based decision support tool for the identification of sustainable treatment options for domestic wastewater.Water Science and Technology, 43(7): 265–269.

Belton, V. & Stewart T. J. (2003). Multi criteria decision analysis: An integrated approach. Kluwer Academic Publishers.2nd print. 2003.ISBN 0-7923-7505-X.

Ellis, K. V. & Tang, S. L. (1990). Wastewater treatment optimization model for developing world, I model development. Journal of Environmental Engineering, (117): 501-518.

Gumbo, B. &Marjanovic, P. (2003). The Role of Decentralised Systems in Meeting Challenges

of Urban Wastewater Management in Africa Contribution to Meeting the Millennium Development Goal 7 – New Project Initiative by WaterNet and UNESCO-IHE

Hidalgo, D., Hirsuta, R, Martinez, L., Fatta, D. and Papadopoulos, A. (2007).Development of a multi-function software decision support tool for the promotion of the safe reuse of treated urban wastewater.Desalination, (215) 90-103

Ilemobade, A. (2003).“Decision support system for rural and peri-urban water distribution system design and operation”. PhD Thesis, Faculty of Engineering & the Built Environment, School of Civil & Environmental Engineering. University of the Witwatersrand, South Africa.

Ilemobade, A. A. and Stephenson, D. (2006). Application of a constrained non-linear hydraulic gradient design tool to water reticulation network upgrade. Urban Water Journal 3(4).199-214.

Ilemobade, A. A., Adewumi, J. R. & J. E. van Zyl (2008). Assessment of feasibility of using dual water reticulation system in South Africa.WRC Report No. 1701/1/09 ISBN 9781770057876

Jackson, R. (1996). Low cost sewerage. 1994. Chichester: J Wiley, 1996. ISBN 0-471-96691-6

Joubert, A. & Stewart, T. (2004). Guidelines for the use 13. of multi criteria decision analysis in the implementation of the national water Act. WRC Report No. 1298/1/04.

Kahinda, J. M., Taigbenu, A. E., Sejamoholo, B. B. P., and Boroto, R. J. (2009). A GIS-based decision support system for rainwater harvesting (RHADESS).Physics and Chemistry of the Earth.34(13-16) 767–775

Malamis, K., Moustakas, K., Papadopoulos, A., Loizidou, M. 2008 Multi-criteria analysis for the determination of the best WEEE management scenario in Cyprus. Waste Management 28 (2008): 1941–1954.

Massoud, M.A.,Tarhini, A., Nasr, J.A. (2007). Decentralised approaches to wastewater treatment and management: Applicability in developing countries, Journal of Environmental Management 90 (2009) 652–659.

Munda, G., Nijkamp, P. &Rietveld, P. (1994).Qualitative multicriteria evaluation for environmental management.Ecological Economics 10 (1994) 97 – 112.

Ndiritu, J. G (2003).Reservoir system optimisation using a penalty approach and a multipopulation genetic algorithm.Water SA 29(3) 273-280.

Ndiritu, J. G., and Daniel, T. M (2001) An improved genetic algorithm for rainfall-runoff model

calibration and function optimization. Mathematical and Computer Modelling.33(6-7) 695-706.

Newman, S., Lynch, T., Plummer, A.A., 1999. Success and failure of decision support systems: learning as we go. In: Proceedings of the American Society of Animal Science.

Palaniappan, M., Lang, M. &Gleick, P.H. (2008). A review of Decision making support tools in the water, sanitation and Hygiene Sector. Wash Pacific Institute.

Safaa, A. A., Shadia, R. T. and Hala, A. T. (2002). Development and verification of a decision support system for the selection of optimum water reuse schemes. Desalination, (152) 339-352.

Tang, S. L. & Ellis, K. V. (1994). Wastewater treatment optimization model for developing world, II model testing. Journal of Environmental Engineering, (120) 610-624.

Tayler, K., Parkinson, J. & Colin, J. (2003). Urban sanitation: A guide to strategic planning. ITDG Publishing. London: UK.

Zapatero, E.G., (1996). A quality assessment instrument for multi-criteria decision support software. Benchamarking for Quality Management and technology 3 (4) 17-27

Zeng, G., Jiang, R., Huang G., Xu, M. & Li, J. (2007). Optimization of wastewater treatment alternative selection by hierarchy grey relational analysis. Journal of Environmental Management 82 (2007) 250–259.