Practices and Hydrological Effects of Road Water Harvesting in Northern Ethiopia: Towards Design of Multi-Functional Infrastructures

Abstract

Infrastructure development (including roads and railways) are among the major investments in many countries in Africa. Road hydraulic structures (road side drainages, culverts and bridges) are mostly designed to discharge concentrated flow of water. Unmanaged water from roads could lead to erosion, flooding, water logging, siltation, and even landslides. To convert such problems into opportunities, road water harvesting (RWH) was systematically promoted in Tigray, northern Ethiopia, in the years 2014-2018. The method/approach used include: (i) participatory selection of RWH technologies, (ii) implementation of the technologies through community mobilization, and (iii) monitoring the hydrological effects/benefits of the interventions (mainly on soil moisture and groundwater levels). Results of the study revealed that harvesting water from road catchments is found to have several benefits: increase in groundwater recharge (enhancing infiltration and reducing flooding), improvement in soil moisture, and increase in availability of surface water in ponds/reservoirs. Road water harvesting/management was found to be an instrument to create resilience to rainfall variability and reduce the negative effects of water from roads; an opportunity which need to be promoted not only in water and land management but also in infrastructural development whereby multi-functional roads could be designed/constructed.