Ecohealth model for groundwater quality improvement on the coastal cities of Cotonou and Lomé in West Africa

The city of Cotonou (Benin) in the delta of the River Ouémé and the city of Lomé (Togo) closed to the River Zio and depending lagoons have hydrosystems include aquifers and urban ecology under pressure of annual floods and discharge. So, bad sanitation and hygiene, poor physicochemical and bacteriological groundwater quality and occurrence of health risks (malaria, gastroenteritis, diarrheal) are observed ecohydrological characteristics. Well water quality data, sanitation and hygiene related public health data linking to the flow data of referred rivers are used to highlight a complexity of the ecohydrological state of the cities. With regard to the global agenda 2030 specifically the SDG 3, 6 and 11, an ecohealth model was developed to contribute in improvement of well water quality and to promote sustainable healthy living in the study area. Elaborated ecohealth model supports pathways on how improved human health could be attained from better groundwater and waste management in the whole west African coastal cities. In Cotonou and Lomé, recurrent floods, controlled by hydrological variation on the depending river basin affects urban ecology and human settlements. The footprint of the interactions is deterioration of environment patterns, of groundwater quality and higher prevalence of waterborne diseases. Referring to knowledge on public health (current and expected status), the model ecohealth is generated by establishing a relationship between floods, aquifers (hydrosystem) and sanitation and hygiene systems (disposal). Given that the urban population faces problems of unsafe sanitation and hygiene, and well water quality degradation, adequate information-education-communication (IEC) for social change approach was used to help in adoption of socio-ecological sanitation systems for water security and its accessibility. Dry toilets, above ground and watertight pit latrines and polyethylene septic tanks are the proposed sanitation disposals. Effective implementation of developed ecohealth model could have great social impacts and help in sustainable well-being in the coastal West African cities.

Keywords: River delta, coastal city, groundwater quality, floods, ecohealth model