Hydrological assessment of sediment transport dynamics in river Watari, Kano State, Nigeria: a field-based study

Abstract

The problem of reduction in the installation capacity of dams, especially in the northern part of the country as a result of rainfall seasonality and sediment load, cannot be overemphasized. The aim of this study is to assess the sediment loads and concentrations in Watari River of Kano State, Nigeria using a field based technique. The methodological approaches employed for primary data collection were field measurements involving reconnaissance survey, measuring of coordinates, monitoring of stream discharges of the five major tributaries upstream using Velocity Area Method from June 2024 to November 2024 which marks the hydrological period in the study area. Water samples were also collected for analysis in the laboratory to determine the suspended sediment load and dissolved sediment concentration. Simple descriptive and statistical tools (ANOVA, Post Hoc test) were used. The suspended sediment load for the five tributaries indicates that Danzabuwa has the highest sediment load of 14,280 mg/l and Kwaski has the lowest value of 6,828 mg/l. However, the result using ANOVA shows that there is no significant difference in the suspended sediment loads for the five tributaries upstream of the Watari River. For the total dissolved sediment, it shows that Kwaski has the highest value of 9,286.4 mg/l and Kokai has the lowest value of 2,387.6 mg/l. However, the results for the dissolved sediment show that there is a significant difference. Therefore, a post hoc multiple comparison test using Tukey’s HDS was conducted. The variation in the total dissolved sediment concentration may be a result of farming activities which predominates the basin especially the Kwaski sub-basin. Recommendations were made among which are: The need to put sustainable land management practices such as controlled grazing and erosion control farming techniques, should be promoted. Continuous monitoring of stream discharges and sediment load by relevant authorities for comprehensive watershed management should be put in place.