Water hyacinth is one of the world’s worst aquatic weeds. It devastates aquatic environments and costs billions of dollars every year in control costs and economic losses. The primary aim of this project is to use Remote Sensing and GIS to monitor the impact of hyacinth on the residents living in coastal area of Ondo State, Nigeria. Landsat images of 1986, 2001 and 2016 of the study areas were obtained. The images were geometrically corrected and ground control points obtained through intensive ground surveys permitted the co-registration of all images to a Universal Transverse Mercator (UTM). The satellites imageries were made to pass through processes of image enhancement, geo referencing, re-sampling, image classification and digitizing. A supervised classification was performed on false colour composites (bands 4, 3 and 2) into the land use and land cover classes. Minimum likelihood algorithm with Arc GIS 9.3 software was also used. Questionnaire was used to determine the effect of water hyacinth on the socio-economic life of the resident. The results reveal that in 1986, water hyacinth covered 18452.29ha which constitute 3.02% of the water body and in 2001, the water hyacinth decreased to an area of 6568.18ha which constitute 0.93% of the study area and a further decrement of 4583.70ha which constitute 0.79% of the study area in 2016. Also between 1986 and 2016 the built-up area increased from 0.80% to 4.23%. The study therefore recommends proper monitoring of water hyacinth using satellite technique which will provide valuable information necessary for planning that would sustain future urban development.

Water Hyacinth, Coastal Area, Remote Sensing, GIS, Satellite Images, Aquatic Environment