9. Quality Characteristics of water used for irrigation in urban and peri-urban agriculture in Greater Accra Region of Ghana: Health and Environmental Risk
Joseph Richmond Fianko, Mavis Korankye
West African Journal of Applied Ecology
Urban Farm DB summary
A study assessed the environmental and health impact of urban and peri-urban irrigated agriculture in Ghana by analyzing the physico-chemical and microbiological characteristics of irrigation water in the Greater Accra Region, calculating a comprehensive pollution index (CPI) and sodium adsorption ratio (SAR). Water samples used for informal irrigation contained significant microbial loads: total coliform ranged from 25×10² to 1209×10² cfu/100ml and E. coli from 2×10² to 651×10² cfu/100ml, with a mean total coliform level (517.917×10² cfu/100ml) far exceeding the recommended maximum guideline values of 5,000 and 1,000 cfu/100ml for irrigation water. CPI values ranged from 0.16 to 0.43 (average 0.27), indicating moderate pollution; about 42% of samples were classified as sodic waters, and SAR values of 3.42 to 24.75 meant nearly all samples exceeded the threshold (SAR > 4) associated with reduced water infiltration and soil permeability problems. The water is described as under persistent pollution pressure from expanding human activity, posing high risks to the health of the environment, farmers, traders, and consumers.