Geospatial mitigation of the effect of undulating terrain on efficient water distribution network: a case study of Enugu Urban, South-Eastern Nigeria

Undulating terrain has continued to aggravate pipe-borne water supply challenges in the Enugu Urban area. The rapid increase in urbanization has worsened the situation. This, therefore, calls for the deployment of systems that can support the effective planning of surface and underground facilities for the development of an efficient water distribution network in this region. Remote Sensing, Geographic Information Systems (GIS), Hydrographic Survey, and Geophysical Survey, collectively referred to as geospatial technologies, have been combined in different ways by developed nations to resolve challenges facing surface and underground facilities. This study, therefore, demonstrates the application of this technology in designing an efficient water distribution network for urban areas with undulating terrain. The spot heights dataset extracted from Light Detection and Ranging (LiDAR) satellite imagery offered the bases for the re-structure of the existing water distribution network map to accommodate the undulation of the topography. This was integrated into a GIS tool to synergize the topography with the radial and dead-end standard water distribution patterns. The result was a sub-division of the Enugu Urban Area into 12 zones with reservoirs at the most elevated points to facilitate water reticulation by gravity. The efficacy of this distribution network map was confirmed suitable with EPANET software. HIGHLIGHTS Designing a functional piped water infrastructure in urban cities requires a holistic view and understanding of the topography of the terrain. This is what geospatial technologies have provided to resolve the perennial scarcity of piped water supplied in the Enugu Urban area.