Roads: Instruments for rainwater harvesting, food security and climate resilience in arid and semi-arid areas

Abstract

With an investment of 7-10 billion USD in sub-Saharan Africa, the development of roads is a major factor in the change of landscapes and the drainage patterns. Thus, roads often act as conveyance systems, but the impact is often negative, leading to erosion, waterlogging and flooding. These impacts come down hardest on the more vulnerable and least resilient, such as poor female-headed households. Yet these negative effects can be turned around and roads can be made into instruments for rainwater harvesting, food security and climate resilience. In this regard, there is a variety of techniques that can be used-ranging from simple interventions in the area surrounding the roads to modified designs of road bodies. What drives the transformation of roads is a change in governance too-better coordination between road builders and water resource and agricultural departments and closer interaction with roadside communities. This chapter provides evidence from Yemen and Tigray region in Ethiopia, where road water harvesting has systematically been introduced in all districts since 2014. The chapter describes the process of promoting road water harvesting, the techniques used, the potential of road water harvesting to increase resilience and the hydrological and socio-economic effects.