A geospatial perspective of flood risk hotspots, transport networks and emergency response services in Accra, Ghana

ABSTRACT

This paper adds to existing knowledge about flood management in Accra and contributes insights into emergency responses to major flood events in a geospatial context. The study identifies and analyses the specific routes from the facilities of emergency responders to designated flood-prone areas within four sites in the peripheral areas of the Greater Accra Metropolitan Area. Flood hotspots were ascertained from several sources including local knowledge and bluespot maps derived from a 10 m resolution elevation model. GIS-based network analysis was used to determine the fastest routes from emergency responder facilities to flood hotspots, based on OpenStreetMap data. Interviews revealed that the computed routes are unsuitable for emergency services due to narrow passages and prevailing conditions during the floods. It is necessary to incorporate the individual responder’s knowledge gained through familiarization with the local terrain to identify the optimal routes. The study further analysed the accessibility of emergency response services using indicative service area maps that present an account of time-distance from various emergency responders’ bases. Finally, the study recommends the need for better planning of the expanding areas of the Greater Accra Metropolitan Area, in terms of accessibility for emergency responders.

KEYWORDS:

• Flood hotspots
• emergency response
• geospatial, transport networks

Disclosure statement

No potential conflict of interest was reported by the author(s).

Ethical consent

All data collection activities for this project have been approved by the Ethics Committee for the Humanities at the University of Ghana (approval code: ECH 182/17–18).

Additional information

Funding

This research was funded by a grant awarded by the Danish Ministry of Foreign Affairs (Danida/DFC/FFU under Grant Number - R445-A31-887/170/01-KU).