Determination of the Rate of Expansion of Magarya River Channel Upstream of Doma Bridge in Gombe Metropolis, Gombe State, Nigeria

The research focused on determining the rate of expansion of the River Magarya Channel upstream of Doma Bridge, Gombe Metropolis. To achieve this, data were gathered from satellite images. The collected data were analyzed using ArcGIS (GIS) software and simple descriptive statistics. The results obtained showed that the Magarya Basin covers an area of 85.74 km². In 1992, gullies covered 2.22 km², which is 3% of the total area. The results also show that the extent of gully erosion in 2022 covered a land area of 5.25 km², making it 6.5% of the total land area of the Magarya Basin. It was concluded that between the years 1992 and 2022, about 3.03 km² of land has converted to gullies due to erosion, with an average rate of 1.1 km² every 10 years. It is recommended that there should be routine inspections of all areas in the community to identify possible future occurrences of gullies and decide on possible ways of controlling the effects of gully erosion on the basin. Additionally, farmers should adopt modern mechanized agricultural practices and ways of mitigating the effects of gully erosion on the basin. The study did not involve a detailed analysis of the economic impacts of gullies but focused on the physical and environmental impacts. The study recommends that further research be conducted on the economic impacts of gullies.