Road Network Connectivity Implications on Urban Wetlands Accessibility in the City of Douala, Cameroon

Abstract

Urban wetlands have an established record to provide essential services such as flood mitigation, water purification, and biodiversity conservation, but the uncoordinated growth of third world cities have triggered an influx into these wetlands. The Douala urban peripheral mangrove wetlands that were non-constructible areas have succumbed to this human pressure which compromises their accessibility and functionality. This study investigates the implications of road network connectivity on urban wetland accessibility in Douala, Cameroon. Field survey of the road transport network was carried out and analyzed for road network connectivity using the Beta index in addition to a survey through targeted questionnaires to 500 households in three wetlands that epitomize the road accessibility trait. Results of the study revealed that the road network of Mambanda and Makepe Missoke is high with 7.1 km/km2 and of 8.1km/km2 while that of Bois des Singes is low with just of 3.5 km/km2. The connectivity of the road network in the wetlands from the beta indices gives a connected road network with Mambanda, Makepe Missoke and Bois des Singes having beta indices of 1.17, 1.11 and 1.02 respectively. The implication is that the urban wetland road connectivity gives a false impression of accessibility for the flux of good and human services that are constraint by the natural hydro geomorphological conditions. There is need to rethink the mobility plight of the urban wetland duellers once left to colonize such inedificandi areas. This study recommends that stakeholders managing these wetlands should engage in the planning of the wetlands in a sustainable, resilient and inclusive way, by improving on the road transportation system and the accessibility of only those areas that do not affect the health of the wetlands and evict the wetland inhabitants from the peripheral highly inaccessible parts where the improvement in accessibility may results in the degradation of the wetlands.