American Journal of Water Resources
ISSN (Print): 2333-4797 ISSN (Online): 2333-4819 Website: Editor-in-chief: Apply for this position
Open Access
Journal Browser
American Journal of Water Resources. 2019, 7(4), 155-162
DOI: 10.12691/ajwr-7-4-4
Open AccessArticle

Assimilation of Pollution Loading on Sosiani River in Eldoret Municipality, Kenya: As a Wastewater Management Strategy

Obiewa James Oduor1, , Kariuki David Kinuthia1 and Damaris Nduta Wachira1

1Department of Chemistry, University of Nairobi, P.O.BOX 30197 Nairobi, Kenya

Pub. Date: November 15, 2019

Cite this paper:
Obiewa James Oduor, Kariuki David Kinuthia and Damaris Nduta Wachira. Assimilation of Pollution Loading on Sosiani River in Eldoret Municipality, Kenya: As a Wastewater Management Strategy. American Journal of Water Resources. 2019; 7(4):155-162. doi: 10.12691/ajwr-7-4-4


In this study, the pollution loading on Sosiani River, in Uasin Gishu County, Kenya, was assessed. The aim of this study was to determine assimilation of pollution loading by the two wastewater treatment plants located in the Eldoret Municipality. Samples were collected from six points along the river, influents and effluents of the treatment plants. Faecal and Total Coliforms, heavy metals; Pb, Cd, Cu and Zn, anions; Cl-, F-, NO3-, PO43- and SO42-, flow and pollution loading points, PLP, were determined. The parameters were determined using experimental procedures. The PLP was 800 and the river’s tolerance limit 10 %, hence a threshold of 880 PLP. Heavy metals’ levels were; Pb 0.583 - 0.970 mg / L, Cd 0.081 – 0.112 mg / L, Cu 0.038 - 0.105 mg / L and Zn 0.097 - 0.116 mg / L. Faecal and Total Coliforms were 25 - 1144 and 120 - 1555 Cfu / 100 ml, respectively. Chemical parameters were in the range; F 0.0125 - 0.469 mg / L, Cl 141.800 - 529.390 mg / L, NO3 2.990- 6.495 mg / L, PO4 0.038 - 4.052 mg / L and SO4 0.319 - 6.424 mg / L. The river flow range was 13920 - 70560 L / minute. The effluent flows were 1560 and 3960 L / minute. The coliforms exceeded the nil Cfu / 100 ml limit. Chloride levels at S2, S4, S6 and phosphate at S6 exceeded the 275 and 0.11 mg / L limits, respectively. The study will provide information on the contribution of the treatment plants to the pollution loading into the river. It will highlight the role of a river volume in determining its assimilative capacity and this will inform decisions made by water service providers on effluent volume.

wastewater pollution loading water resource assimilation tolerance limit

Creative CommonsThis work is licensed under a Creative Commons Attribution 4.0 International License. To view a copy of this license, visit


Figure of 3


[1]  WRMA (Water Resources Management Authority), Effluent Discharge Thresholds, July 2009.
[2]  UN-Water, Waste Water Management. A UN-Water Analytical Brief, 2015.
[3]  Ontumbi, G., Nyabero, C. and Sang, C.C., An Assessment of Water Quality Variation on Human Health in the River Sosiani Catchment, Kenya, International Journal of Innovation and Research in Educational Sciences, 2 (2), 63-68, 2015.
[4]  Wang, H., Wang, T., Zhang, B., Li, F., Omosa, I.B., and Pradhan, M., Water and Wastewater Treatment in Africa – Current Practices and Challenges, Clean-soil, Air, Water, 42 (8), 1029-1035, January 2014.
[5]  WASREB (Water Services Regulatory Board), Guidelines on Drinking Water Quality and Effluent Monitoring, March 2008.
[6]  WRMA (Water Resources Management Authority), Strengthening Regulations for Sustainable Water Resources Management in Kenya, March 2015.
[7]  Andersson, K., Rosemarin, A., Lamizana, B., Kvarnstron, E., McCoville, J., Seidu, R. and Trimmer, C., Sanitation, Wastewater Management and Sustainability: from Waste Disposal to Resource Recovery. Nairobi and Stockholm: United Nations Environment Programme and Stockholm Environment Institute, 2016.
[8]  Jhansi, S.C., Shah, M. and Mishra, S.K., Wastewater Treatment and Reuse: Sustainability Option, The Journal of Sustainable Development, 10 (1), 1-15, 2013.
[9]  UN (United Nations), The Sustainable Development Goals Report, 2016.
[10]  Government of the Republic of Kenya, Sessional Paper No. 10 of 2012 on Kenya Vision 2030, 2012.
[11]  Ndwiga, T., Selected Trace Elements in Domestic Water Boreholes and Their Implications on Human Health in Huruma Estate, Eldoret Municipality, Uasin-Gishu County, Kenya. Journal of Environmental Protection, 5, 65-65, 2014.
[12]  LVNWSB (Lake Victoria North Water Services Board), World Bank Funds More Projects. Africa Water, Sanitation and Hygiene, 8 (4), 32-35, December 2013.
[13]  Masakha, E.J., Moturi, W.N. and Ogendi, G.M., Microbiological Water Quality of Urban Streams and the Health Implications: Case Study of Sosiani River Eldoret Municipality, Kenya, Journal of Environmental and Earth Science, 7 (6), 5-13, 2017.
[14]  Meme, F.K., Arimoro, F.O. and Nwadukwe, F.O., Analyses of Physical and Chemical Parameters in Surface Waters nearby a Cement Factory in North Central, Nigeria, Journal of Environmental Protection 5, 826-834, July 2014.
[15]  Ogendi, G.M, Getabu,A.M., Onchieku, J.M. and Babu, J.M., An Assessment of Some Physical, Chemical and Biological Characteristics of Nyanchwa – Riana River Flowing through Kisii Town in South West Kenya. International Journal of Applied Science and Technology 5 (2), 68-79, April 2015.
[16]  Wagner, R.J., Boulger, R.W. and Smith, B.A., Revised Guidelines and Standard Procedures for Continuous Water Quality Monitors: Station operation, record computation and data reporting. 2005.
[17]  Patil, P.N., Sawant, D.V. and Deshmukh, R.N., Physico – Chemical Parameters for Testing of water. International Journal of Environmental Sciences 3 (3), 1194-1207, November 2012.
[18]  Halder, J.N. and Islam, M.N., Water Pollution and its Impact on the Human Health, Journal of Environment and Human Health 2 (1), 36-46, January 2015.
[19]  Obiewa, J.O., Mineral Composition of Some Selected Indigenous Vegetables and Soil in Kendu Bay, Homa Bay County, Kenya, International Journal of Scientific and Educational Studies, 1 (2), 10-19, December 2015.
[20]  Bedu-Addo, K. and Akanwarewiak, W.G., Determination of the Pollution Loads of Brewery X and the Impacts of the Pollutant on the Sisai River, Journal of Public Health and Epidemiology, 4 (10), 316-319, December 2012.
[21]  Lente, I., Ofosu-Anim, J., Brimah, A.K. and Atiemo, S., Heavy Metal Pollution of Vegetable Crops Irrigated with Wastewater in Accra, Ghana, West African Journal of Applied Ecology, 21 (1), 41-58, 2014.
[22]  Dulo, S.O., Determination of Some Physico-Chemical Parameters of the Nairobi River, Kenya. J. Appl. Sci. Environ. Manage 12 (1), 57-62, March 2008.
[23]  WHO (World Health Organization), Guidelines for Drinking-Water Quality, Fourth edition, WHO Press, Geneva, 2011.