Document Type : Research Paper


1 Department of Geography, Faculty of Law, Arts and Social Sciences, Kenyatta University, Nairobi, Kenya.

2 Soil, Water and Environmental Engineering Department (SWEED), Faculty of Biosystem and Environmental Engineering (SoBEE), Jomo Kenyatta University of Agriculture and Technology (JKUAT), Nairobi, Kenya.

3 Department of Water and Agricultural Resource Management, Faculty of Agriculture, University of Embu, Embu, Kenya of Embu.



Surface water pollution is a challenge due to effluent discharge from land-based factors like agro-based sectors, settlements, and poor sanitation. The research investigated the spatial and seasonal variation of physico-chemical and biological water quality due to land use changes along the Thika River sub-catchment, Upper Tana, Kenya. The study applied purposive sampling technique from the different zones within the catchment during the dry and wet season of 2021. The samples were tested for physico-chemical and microbial contaminants. R-studio was used to calculate the mean values and t-test performed at a 95% confidence interval to determine variation of the parameters in the two seasons and mean levels compared to the Kenya Bureau of Standards (KEBS) 2010 and the World Health Organization (WHO) acceptable quality for drinking water. There was significant variation in sulphate and nitrate concentration, total coliform and fecal coliform and no significant variations in physical parameters throughout the seasons. The total coliform and fecal coliform exceeded KEBS and WHO limits.


Abowei, J. F. N., (2010) ‘Salinity, dissolved oxygen, ph and surface water temperature conditions in Nkoro river, Niger Delta, Nigeria’, Advance Journal of Food Science and Technology, 2(1), pp. 36-40.
Adongo, M. J. et al. (2022) ‘Seasonal variation in physicochemical properties of groundwater, a case study of Kamiti-Marengeta Subcatchment Kiambu, Kenya’, Journal of Water Resource and Protection, 14(2), pp. 72-85.
Benedict, M., Khaldoon, A. and Omondi, B. (2018) ‘Uncertainty analysis and calibration of swat model for estimating impacts of conservation methods on streamflow and sediment yield in Thika River Catchment, Kenya’, International Journal, 3(1), pp. 1-11.
Bwire, G. et al. (2020) ‘The quality of drinking and domestic water from the surface water sources (Lakes, Rivers, irrigation canals and ponds) and springs in cholera prone communities of uganda: An analysis of vital physicochemical parameters’, BMC Public Health, 20(1), pp. 1-18.
Cotruvo, J.A. (2017) ‘WHO guidelines for drinking water quality: First Addendum to the Fourth Edition,’ Journal‐American Water Works Association, 109(7), pp. 44-51.
David, M. M., John, W. K. and Bonface, J. (2017) ‘Bacteriological and physicochemical characterization of aora loko stream water, Maseno, Kenya’, Journal of Asian Scientific Research, 7(4), pp. 119.
Dehghan, F., Karami, J. and Yazdanbakhsh, K. (2021) ‘Predicting environmental behavior by relying on water consumption behavior based on environmental awareness, attitude and concern’, Journal of Applied Research in Water and Wastewater, 8(2), pp. 113-117.
Edokpayi, J. N. et al. (2015) ‘Temporal variations in physico-chemical and microbiological characteristics of Mvudi river, South Africa’, International Journal of Environmental Research and Public Health, 12(4), pp. 4128–4140.
Githinji, M. W., Mwaura, F. and Wamalwa, J. (2019) ‘Land use and water pollution along the altitudinal gradient of the Likii river, Laikipia County, Kenya’, Journal of Environment Pollution and Human Health, 7(1), pp. 39-52.
Ibekwe, A. M., Ma, J. and Murinda, S. E. (2016) ‘Bacterial community composition and structure in an urban river impacted by different pollutant sources’, Science of the Total Environment, 566, pp. 1176-1185.
Kambwiri, A. M. et al. (2014) ‘Land use impacts on water quality of rivers draining from Mulanje mountain: A case of Ruo river in the Southern Malawi’, Malawi Journal of Science and Technology, 10(1), pp. 15-31.
Kithiia, S. M. (2007) ‘An Assessment of water quality changes within the athi and nairobi river basins during the last decade’, IAHS Publication, 314, pp. 205.
Langat, P. K. et al. (2021) ‘Monitoring of land use/land-cover dynamics using remote sensing: A Case of Tana River Basin, Kenya’, Geocarto International, 36(13), pp. 1470-1488.
Ly, K., Metternicht, G. and Marshall, L. (2020) ‘Linking changes in land cover and land use of the lower mekong basin to instream nitrate and total suspended solids variations’, Sustainability, 12(7), pp. 2992.
Mekuria, D. M., Kassegne, A. B. and Asfaw, S. L. (2021) ‘Assessing pollution profiles along little Akaki river receiving municipal and industrial wastewaters, central Ethiopia: Implications for environmental and public health safety’, Heliyon, 7(7), pp. e07526.
Ngatia, M., Kithiia, S. M. and Voda, M. (2023) ‘Effects of anthropogenic activities on water quality within Ngong river sub-catchment, Nairobi, Kenya’, Water, 15(4), pp. 660.
Njogu, I. N. and Kitheka, J. U. (2017) ‘Assessment of the influence of rainfall and river discharge on sediment yield in the upper Tana catchment in Kenya’, Hydrology Current Research, 8(1), pp. 263.
Njue, N. et al. (2016) ‘Influence of land use activities on riparian vegetation, soil and water quality: an indicator of biodiversity loss, Southwest Mau Forest, Kenya’, Open Journal of Forestry, 6(5), pp. 373-385.
Njuguna, S. M. et al. (2020) ‘Application of multivariate statistical analysis and water quality index in health risk assessment by domestic use of river water: Case study of Tana river in Kenya’, Process Safety and Environmental Protection, 133, pp. 149-158.
Noori, R. et al. (2010) ‘Multivariate statistical analysis of surface water quality based on correlations and variations in the data set’, Desalination, 260(1-3), pp. 129-136.
Nouri, M. and Montazer Faraj, A. (2022) ‘Monitoring and assessment of water quality in Tehran city using physicochemical and microbial indexes’, Journal of Applied Research in Water and Wastewater, 9(2), pp. 22-25.
Nyilitya, B. et al. (2021) ‘Nitrate source apportionment in the complex Nyando Tropical river basin in Kenya’, Journal of Hydrology, 594, pp. 125926.
Ogendi, G. M. et al. (2015) ‘Assessment of the microbial load of Nyanchwa-Riana and Nyakomisaro-Riana rivers, Kisii, Kenya’, International Journal of Fisheries and Aquatic Studies, 2(6), pp. 182-192.
Ondigo, D. A., Kebwaro, J. and Kayoo, A. M. (2018) ‘Water resources and management under increasing urban demography: A Kenyan perspective, A review’, Journal of Water Resource and Protection, 10, PP. 919.
Ondoo, K. O. et al. (2019) ‘Determination of selected water quality parameters in river Sio, Busia County, Kenya’, International Research Journal of Pure and Applied Chemistry, 18(3), pp. 1-16.
Ontumbi, G., Obando, J. and Ondieki, C. (2015) ‘The influence of agricultural activities on the water quality of the river Sosiani in Uasin Gishu county, Kenya’, International Journal of Research in Agricultural Sciences, 2(1), pp. 2348-3997.
Onywere, S. M. et al. (2007) ‘Intensification of agriculture as the driving force in the degradation of Nzoia river basin: The challenges of watershed management,’ LARS,
Ouma, S. O. et al. (2016) ‘Seasonal variation of the physicochemical and bacteriological quality of water from five rural catchment areas of lake Victoria Basin in Kenya’, Journal of Environmental Analytical Chemistry, 3(170), pp. 2.
Rasi Nezami, S. and Aghlmand, R. (2023) ‘Assessing the suitability of river water quality using water quality indices: A case study on Balikhlou river in Northwest of Iran’, Journal of Applied Research in Water and Wastewater, 10(1), pp. 1-6.
Sang, J. K. and Maina, C. W. (2018) ‘Modelling the impacts of structural conservation measures on sediment and water yield in Thika-Chania Catchment, Kenya’, International Soil and Water Conservation Research, 6(2), pp. 165-174.
Shah, K. A. and Joshi, G. S. (2017) ‘Evaluation of water quality index for River Sabarmati, Gujarat, India’, Applied Water Science, 7, pp. 1349-1358.
Sila, O. N. A. (2019) ‘Physico-chemical and bacteriological quality of water sources in rural settings, a Case study of Kenya, Africa’, Scientific African, 2, pp. e00018.
TNC (2015) Upper Tana-Nairobi water fund business case. Version 2. The Nature Conservancy: Nairobi, Kenya.
TNC (2016) Sub-Saharan Africa’s urban water blueprint: securing water through water funds and other investments in ecological infrastructure. The Nature Conservancy: Nairobi, Kenya.
United Nations world water development (2015), Water for a sustainable world (Vol. 1). UNESCO Publishing. ePub ISBN978-92-3-100099-7
van Vliet, M. T. et al. (2013) ‘Global river discharge and water temperature under climate change’, Global Environmental Change, 23(2), pp. 450-464.
Waithaka, A., Murimi, K. S. and Obiero, K. (2020) ‘Effects of temporal rainfall variability on water quality of River Ruiru, Kiambu County, Kenya’, ChemSearch Journal, 11(1), pp. 59-65.
Wilson, M. M., Michieka, R. W. and Mwendwa, S. M. (2021) ‘Assessing the influence of horticultural farming on selected water quality parameters in Maumau stream, a tributary of Nairobi river, Kenya’, Heliyon, 7(12), pp. e08593.