Application of Geographical Information Systems (GIS) and Analytical Hierarchy Process (AHP) in the Selection of A Suitable Sanitary Landfill Site for Solid Waste Disposal

Abstract

Shortage of land for waste disposal and inappropriate dump sites is the biggest problems in the Niger Delta Area of Nigeria, Warri in particular. This problem has its negative impact on human and environment owing to the menace often caused by indiscriminate dumping of solid waste. The swamping nature of the soil and the irregular topographic nature of the land hinder the flow of accumulated water formed by rains. This makes runoff during the rainy season almost impossible leading to flood in most cases. To select an appropriate site for landfill, there is need to consider different alternative areas using numerous criteria’s before making decision. In this study, geographical information systems (GIS) and analytical hierarchy process (AHP) were employed to analyze selected criteria’s that can influence the selection of a suitable site for sanitary landfill application in Warri, Delta State, Nigeria. The selected criterions include; flood extent, stream, rivers, swampy areas, ground water, built-up areas, roads, slopes, airport, palaces and point of interests (POIs). Features of interest such as roads, built-up areas, swampy areas, rivers and streams in the SPOT 5 satellite imagery were converted to vector format by digitizing in order to create a geographic database dataset. Weighted Overlay Linear Combination for map superimposition was adopted while constraints and factors were employed as the criteria for decision-making process.  Suitability rating value of 1 to 5 meaning; not suitable, least suitable, moderately suitable, highly suitable and mostly suitable was use as the final index for land suitability.  Results of the weighted overlay revealed three potential sites within the study area and they include; site 1, site 2, and site 3 with 3.334, 5.418 and 47/582 hectares of land suitable for sanitary landfill applications.

Keyword: Sanitary landfill, weighted overlay, Suitability rating, geographical information systems (GIS), analytical hierarchy process (AHP)

DOI: 10.7176/JNSR/10-2-02

Publication date: January 31^st 2020