Biological Assessment of Water Quality: A Study of Challawa River Water Kano, Nigeria

Abstract

This study was carried out to survey the biotic community of Challawa river water in Kano, Nigeria, using Biological Monitoring Working Party Score (BMWP) and Average Score Per Taxa (ASPT) assessment tools to evaluate the water quality in the field. Using standardized sampling technique insects, insects’ larvae, benthic invertebrates, fresh water vivalve, prosobranch and Pulmonate Gastropods of the river were collected, indentified using identifications keys and BMWP score table. BMWP performances and ASPT values obtained were recorded for each selected site A, B, C and D during sampling period between February to October. The results revealed that Site A, close to water treatment plant, had a total of 63 species count, the total performance of 53 BMWP score; was (high)10 in March but fell sharply to 2(low) in May and the ASPT value obtained was 0.84 as the less sensitive species dominate the sample size and indicating water of B-class quality. Site B, the water intake Station of the Challawa water works had 37 species count, 44 BMWP performances and 1.19 ASPT value assessed A-class. Site C, industrial effluent discharge point, had 51 counts, 28 BMWP performances with 0.55 ASPT value assessed D-class. Site D, the confluent point between River Challawa and River Kano had 67count, 58 BMWP performances and 0.87 ASPT value assessed B-class. The implications of the findings were discussed and recommendations for possible abatement of the situation made.

Key words: Macro invertebrates, quality, assessment, Challawa River, ASPT, BMWP