Physicochemical and Heavy Metal Characterization of River Kapingazi in Embu County, Kenya

Authors

  • Naomy Chepkirui Yego

    Department of Water and Agricultural Resource Management, University of Embu, Embu P.O. Box 6-60100, Kenya
  • Charles Onyari Nyambane

    Department of Water and Agricultural Resource Management, University of Embu, Embu P.O. Box 6-60100, Kenya
  • Rebbecca Yegon

    Department of Water and Agricultural Resource Management, University of Embu, Embu P.O. Box 6-60100, Kenya
  • Shadrack Kiprotich

    Department of Agricultural Economics and Extension, University of Embu, Embu P.O. Box 6-60100, Kenya

DOI:

https://doi.org/10.30564/re.v7i3.9873
Received: 5 May 2025 | Revised: 23 May 2025 | Accepted: 30 May 2025 | Published Online: 4 July 2025

Abstract

Surface water provides crucial support to the aquatic ecosystem and humans in numerous ways. However, its quality is paramount in determining its impact on the health of the aquatic ecosystem and humans. Currently, the malady of pollution arising from anthropogenic activities poses a significant threat to the quality of most rivers. The quality of water in the Kapingazi river in Embu County has received limited attention which is a concern that needs to be addressed. This study therefore, sought to investigate the status of water quality in river Kapingazi. The study analyzed 96 samples from four locations in a span of eight months which combined the dry and wet seasons of the year. Parameters measured in-situ included turbidity, pH, total dissolved solids (TDS), temperature, dissolved oxygen (DO) and electrical conductivity (EC) while ex-situ parameters were phosphates, nitrates and concentrations of heavy metals: iron and manganese. Results showed that Water Quality Index (WQI) during the drought period was74.05, suggesting that the water quality is only recommended for agricultural and industrial applications. During wet season, the water quality index was 89.67, reflecting a poor status, as more contaminants were likely introduced through surface runoff. Overall, the WQI averaged to 88.02.  This study concludes that water in River Kapingazi is not suitable for human consumption; therefore, appropriate treatment is essential prior to its use. Similarly, the findings indicate that both rainy and drought periods significantly affect water quality, presenting challenges for its use for various purposes. It is recommended that the allocation of resources towards water treatment facilities and regulation of pollution sources should be enforced to ensure the safety of river water for diverse applications.

Keywords:

Water Quality; Heavy Metals; River Kapingazi; Pollution; Physical & Chemical Parameters

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How to Cite

Naomy Chepkirui Yego, Charles Onyari Nyambane, Rebbecca Yegon, & Shadrack Kiprotich. (2025). Physicochemical and Heavy Metal Characterization of River Kapingazi in Embu County, Kenya. Research in Ecology, 7(3), 104–114. https://doi.org/10.30564/re.v7i3.9873

Issue

Vol. 7, Iss. 3 (August 2025)(in progress)

Article Type

Articles

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Copyright © 2025 Naomy Chepkirui Yego, Charles Onyari Nyambane, Rebbecca Yegon, Shadrack Kiprotich

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This is an open access article under the Creative Commons Attribution-NonCommercial 4.0 International (CC BY-NC 4.0) License.

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