Assessment of Water Hardness and Electrical Conductivity of Borehole Water in Katsina State

Borehole water supplies are the primary source of potable water for a large proportion of rural and semi-urban households in Katsina State, North West Nigeria. The physical and chemical properties of borehole water, including hardness and electrical conductivity, are important indicators of water quality and safety for domestic use. This study assesses the water hardness and electrical conductivity of borehole water samples collected from 30 boreholes distributed across Katsina, Dutsin-Ma, and Funtua local government areas. Samples are analysed using EDTA titration for total hardness and a calibrated conductivity meter for electrical conductivity. Temperature correction is applied to all conductivity measurements. Results indicate total hardness values ranging from 64 to 420 mg per litre as calcium carbonate, with samples from areas underlain by crystalline basement rocks exhibiting the highest hardness. Electrical conductivity ranges from 212 to 1,840 microsiemens per centimetre, reflecting varying mineral dissolution levels linked to geological substrate. Six borehole samples exceed the WHO guideline value of 500 mg per litre for total hardness, and four samples exceed the conductivity threshold of 1,500 microsiemens per centimetre. The findings are directed at the Katsina State Rural Water Supply and Sanitation Agency to inform water treatment strategy. Keywords: water hardness, electrical conductivity, borehole water, Katsina State, water quality