Modelling water demand and efficient use in Mbagathi sub-catchment using WEAP

  • Nyika J
  • G N Karuku
  • R N Onwonga
Keywords: Water systems, WEAP model, High population


Water systems have complex component interactions necessitating development and evaluation of management amidst uncertainties of climate and constrained natural resources. Conceptual models such as WEAP when used are effective planning and management tools as they forecast future effects of resource use efficiency at sub-catchment level using existent hydrological and climate data thereby acting as corrective measure to poor resources management. This study aimed at using WEAP model to forecast demand and analyze scenarios on efficient water use in Mbagathi sub-catchment. WEAP model schematic was set to develop current and reference scenarios. Parameters used to run WEAP model were a GIS map of the sub-catchment, climate data from Kenya Meteorological Department at Dagorretti Corner Station, hydrological and water demand data from WRMA databases. High population growth and prolonged drought were predicted to increase water demand while reuse though not practised, was found by the model to be the most effective approach to manage unmet demands as compared to reduced conveyance losses and increased reservoir capacity. The study concluded that water reuse through exploitation of wastewater could be a viable solution to Mbagathi sub-catchment's water problems.


Abrishamchi, A., Alizadeh, H. & Tajrishy, M. (2007).Water resources management scenario analysis in the Karkheh river basin, Iran using the WEAP model. Hydrological Science and Technology, 23 (1-4), 1-10.
Alfarra, A. (2004). Modelling water resource management in Lake Naivasha. Msc. Thesis, International Institute for Geo-Information Science and Earth Observation.
Ali, M. Y., Waddington, S. R., Timsina, J., Hodson, D., and Dixon, J. (2009). Maize-rice cropping systems in Bangladesh: status and research needs. Journal of Agricultural Science and Technology USA, 3(6), 35–50.
Amarasinghe, U.A., Sharma, B.R., Aloysius, N., Scott, C., Smakhtin, V. and de Fraiture, C. (2005).Spatial variation of water supply and demand across river basins of India. Research Report 83. Colombo, Sri Lanka: International Water Management Institute.
Ansari, M. (2013). The water demand management in the Kingdom of Bahrain. International Journal of Engineering and Advanced Technology, 2 (5), 544-554.
Arampatzis, G. and Evangelides, C. (2016).Water losses during distribution and application in collective pressurized irrigation networks. Journal of Irrigation and Drainage Engineering, 111 (3), 265-275.
Arranz, R. (2006). Future water demands and resources in the Olifants catchment, South Africa: A scenario analysis approach using the WEAP model. Thesis, Colorado State University.
Azad, R. and Sarwar, T. (2014).Effect of watercourse aging on conveyance efficiency and water productivity in District Muzaffarabad, Azad Jammu and Kashmir. Sarhad Journal of Agriculture, 30 (4), 466-471.
Azlinda, S. and Mohd, A. (2008).Assessment of water demand in Langat catchment using water evaluation and planning (WEAP).Hydrology, 4, 18-31.
Bäumle, R., C. Neukum, J. Nkhoma, and O. Silembo. 2007. The Groundwater Resources of SouthernProvince, Zambia (Phase 1) Volume 1 – Technical Report. Prepared by Department of Water Affairs, Ministry of Energy and Water Development, Lusaka; and the German Federal Institute for Geosciences and Natural Resources, Hannover. Project No. BMZ PN 2003.2024.2/BGR 05-2315-01, Lusaka, Zambia, November 2007.
Bharati, L., Smakhtin, V. and Anand, B. (2009). Modelling water supply and demand scenarios: the Godavari-Krishna inter-basin transfer, India. Water Policy, 11 (1), 140-153.
Bhardwaj RM. 2005. Status of Wastewater Generation and Treatment in India, IWG-Env Joint Work Session on Water Statistics, Vienna, 20-22 June 2005.
Conway, D., Persechino, A., Ardoin-Bardin, S., Hamandawana, H., Dieulin, C., and Mahé, G. (2009). Rainfall and Water Resources Variability in Sub-Saharan Africa during the Twentieth Century, Journal of Hydrometeorology, 10, 41–59.
Chu J, Chen J, Wang C and Fu P. (2004). Wastewater reuse potential analysis: implications for China's water resources management. Water Resources 38(11): 2746- 2756.
Dan, N., Khoa, L., Thanh, B., Nga, P. &Visvanathan, C. (2011). Potential of wastewater reclamation to reduce freshwater stress in Ho Chi Minh city Vietnam. Journal of Water Sustainability, 1 (3), 279-287.
Dienya, R. (2007). Application of the WEAP model in integrated water resources management of the Nyando River Basin, Kenya. Msc. Thesis, Jomo Kenyatta University of Agriculture and Technology.
Droogers, P. (2009). Climate change and hydropower, impact and adaptation costs: case study Kenya. Report Future Water, 85.
Droogers, P. and Terink, W. (2014).Water allocation planning in Pungwe Basin, Mozambique. Report Future Water, 129.
Flores-Lopez, F., Galaitsi, S., Escobar, M. & Purkey, D. (2016). Modelling of Andean Paramo ecosystems' hydrological response to environmental change. Water, 8 (94, 1-18.
Flores-Lopez, F. and Yates, D. (2013).A water system model for exploring electric energy alternatives in southeastern US basins. Environmental Research Letters, 8, 1-11.
Friedler, E. and Penn, R. (2011).Study of the effects of on-site grey water reuse on municipal sewer systems. Grand Water Research Institute. Retrieved on 08 February 2016.
Gichuki, N. and Kiteme, B. (2000). Water management constraints and opportunities: A case study of the Upper Ewaso Ngiro North Basin. Eastern and Southern Africa Journal, 8 (1), 15-28.
Grieg-Gran, M., Noel, S. and Porras, I. (2006). Lessons learned from payments from environmental services. Green Water Credits report No. 2. ISRIC, Wageningen.
Hamlat, A., Errih, M. and Guidoum, A. (2011).Simulation of water resources management scenarios in western Algeria watersheds using WEAP model. Arabian Journal of Geosciences, 1 (22), 2225-2236.
Ingol-Blanco, E. and McKinney, D. (2013).Development of a Hydrological Model for the Rio Conchos Basin. Journal of Hydrologic Engineering, 10.1061/(ASCE)HE.1943-5584.
Jaetzold, R., Schmidt, H., Hornetz, B., andShisanya, C. (2006).Ministry of Agriculture Farm Management. Handbook of Kenya (Vol. II, 2nd ed., Part C, Subpart C1). Nairobi, Kenya: Ministry of Agriculture.
Jamal, A. (2013). Using treated wastewater as a potential solution of water scarcity and mitigation measure of climate change in Gaza Strip, Journal of Water Resources and Ocean Science, 2 (5), 79-83.
Katana, S., Munyao, T. and Ucakuwun, E. (2013). Hydrological impacts of land cover changes in upper Athi River Catchment, Kenya. International Journal of Current Research, 5 (5), 1187-93.
Kaur, R., Dhir, G., Kumar, P., Laishram, G., Ningthoujam, D. and Sachdeva, P. (2014). Wastewater production, treatment and use in India. ICAR News (Jan-Mar) 18(1), 7-8.
Khan, A., Richards, K., McRobie, A., Fischer, G., Wiberg, D., Burek, P. & Satoh, Y. (2016). Accuracy assessment of ISI-MIP modelled flows in the Hidukush- Karakoram-Himalayan basin. Geophysical Research Article, 18, 650-666.
Kinoti, J., Mavengano, S., Zhongbo, S. &Becht, R. (2010). Water allocation as a planning tool to minimize water use conflicts in the Upper Ewaso Ng'iro North basin, Kenya. Water Resources Management, 24 (14), 3939-3959.
Koskei, K. and Ngigi, T. (2013).Assessing changes on the floodplain of sandy rivers using geospatial techniques: case of Athi sub-catchment in Makueni. International Journal of Science and Research, 6 (14), 2024-27.
Krause, P., Boyle, D. & Base, F. (2005).Comparison of difference efficiency criteria for hydrological model assessment. Advances in Geosciences, 5, 89-97.
Krhoda, G. (2002). Nairobi river basin phase II: The monitoring and sampling strategy for Ngong/Motoine River, pp.55.
Kuria, Z.N. 2008.Groundwater Resources Assessment of Lamu Island along Coastal Kenya. Prepared for National Museums of Kenya, November 2008, Nairobi.
Kusanto, N. (2013). Sustainable water infrastructure: Water management and reuse.
Le Roy, E. (2006). A study of the development of water resources in the Olifants catchment, South Africa: Application of the WEAP model. Retrieved on 20 May 2015 from
Manatunge, J., Priyadarshana, T., and Nakayama, M. (2010) Environmental and social impacts of reservoirs: Issues and mitigation. Oceans and Aquatic Ecosystems, 1, 1-13.
Mango, L., Melesse, A., McClain, M., Gann, D. & Setegn, S. (2011). Hydro-meteorology and water budget of the Mara river basin under land use change scenarios. Springer Publishers, 39-62.
McCartney, M. P. and Arranz, R. 2007.Evaluation of historic, current and future water demand in the Olifants River Catchment, South Africa. Colombo, Sri Lanka: International Water Management Institute. 48p. (IWMI Research Report 118).
Metcalf and Eddy. 2007. Water reuse. Issues, technologies, and applications. McGraw-Hill Publisher, New York.
Moriasi, D., Arnold, J., van Liew, M., Bingner, R., Harmel, R. & Veith, T. (2007). Model evaluation guidelines for systematic qualification of accuracy in watershed simulations. American Society of Agricultural and Biological Engineers, 50 (3), 885-899.
Mounir, Z., Ming Ma., C and Amadou, I. Application of Water Evaluation and Planning (WEAP): A model to assess future water demands in the Niger river (In Niger Republic). Modern Applied Science, 5 (1), 39-52.
Mugatsia, A. (2010). Simulation and scenario analysis of water resources management in Pekerra catchment using WEAP model. MSc. Thesis, Moi University.
Mulwa, J. (2001). Geological and structural set-up of Kiserian-Matathia area and its influence on groundwater flow and distribution. Msc. Thesis, University of Nairobi.
Mumma, A., Lane, M., Kairu, E., Tuinhof, A. and Hirji, R. (2011).Kenyan groundwater governance case study. The Water Unit, Transport, Water and ICT Department, Sustainable Development Vice Presidency.
Mundia, C. & Aniya, M. (2006). Dynamics of land use/cover changes and degradation of Nairobi city, Kenya. Land Degradation and Development, 17 (1), 97-108.
Ndomba, P., Mtalo, F., and Killingtveit, A. (2008) SWAT model application in a data scarce tropical complex catchment in Tanzania. Physical Chemistry of the Earth, 33, 626–632.
Notter, B., Huruni, H., Wiesmann, U. & Abbaspour, K. (2012).Modelling water provision as an ecosystem service in a large African river basin. Hydrology and Earth System Sciences, 16, 69-86.
Nyikai, R. (2003). Commercial and subsistence farming: What is the future for smallholder Kenyan agriculture? African Crop Science Conference Proceedings, 6, 591-596.
Olago, P. and Aketch, F. (2000).Pollution assessment in Nairobi River basin. Pollution Assessment Report of the Nairobi River basin. Africa Water Network.
Purkey, D., Joyce, B., Vicuna, M., Hanemann, L., Yates, D. and Dracup, J. (2008). Robust analysis of future climate change impacts on water for agriculture and other sectors: a case study in the Sacramento Valley. Climate Change, 87 (1), 109-122.
Rahma, U. (2009). Evaluation of urban water supply options using WEAP: the case of Nablus city. MSc. Thesis, An-Najah National University.
Rukuni, S. (2006).Modelling the response of small multi-purpose reservoirs to hydrology for improved rural livelihoods in the Mzingwane catchment: Limpopo Basin. Retrieved on 25 June 2015 from Retrieved on 14 February 2016.
Santhi, C., Arnold, J. G., Williams, J. R., Dugas, W. A., Srinivasan, R., and Hauck, L. M. (2001) Validation of the SWAT model on a large river basin with point and nonpoint sources, Journal of American Water Resources Association, 37, 1169–1188.
Shawul, A., Alamirew, T. &Dinka, M. (2013). Calibration and validation of SWAT model and estimation of water balance components of Shaya mountainous watershed, Southeastern Ethiopia. Hydrology and Earth System Sciences, 10, 13955-13978.
Smith, M., de Groot, D., and Bergkamp, G. (2006).Establishing payments for watershed services. IUCN, Gland; 109pp.
Sultan, T., Latif, A., Shakir, S., Kheder, K. and Rashid, U. (2014).Comparison of water conveyance losses in unlined and lined watercourses in developing countries. Technical Journal University of Engineering and Technology, 19 (2), 24-27.
Tena, B., Rao, S. &Abbulu, Y. (2016).WEAP modelling of surface water resources allocation in Diadessa sub-basin, West Ethiopia. Sustainable Water Resources Management, 2 (1), 55-70.
Thubu, J. (2012). Developing a sustainable water management plan for Ruiru, Thiririka and Ndarugu basins in Kenya using WEAP. MSc. Thesis, Jomo Kenyatta University of Agriculture and Technology.
Uitto, J.I. (2004). Multi-country cooperation around shared waters: role of monitoring and evaluation, Global Environmental Change, 14, 5–14.
Vicuna, S., Garreaud, R. & McPhee, J. (2010) Climate change impacts on the hydrology of a snowmelt driven basin in semiarid Chile. Climate Change. Springer Publishers.
Wada, Y., van Beek, L. P., van Kempen, C. M., Reckman, J. W., Vasak, S.,and Bierkens, M. F. (2010). Global depletion of groundwater resources. Geophysical Research Letters, 37(20), L20402.
Wilson, K. (2016). Reducing water losses with intelligent pressure management.
Yates, D., Miller, K., Wilby, R. and Kaatz, L. (2015).Decision centric adaptation appraisal for water management across Colorado's continental divide. Climate Risk Management, 10, 35-50.
Zoltay, V. (2007). Integrated watershed management modelling: optimal decision making for natural and human components. MSc. Thesis, Tufts University.