4.2 Fodder grown from road culvert water, South Gondar, Ethiopia

ponds, soak pits, infiltration galleries, terraces, and eyebrows—throughout the watershed. In untreated areas, approximately 8–12 percent of the runoff is retained, but intensive water harvesting can double or triple this proportion, potentially exceeding 30 percent of the runoff. Harvesting larger amounts of water can also reduce the volume of potentially destructive stormwater in the lower part of the watershed. Intensive water retention can store a large amount of water and can change the water cycle of large areas by affecting water availability for crops and soil processes that accelerate natural fertilization, and by creating microclimates that are more conducive to vegetation and agriculture, thus reducing the risks of drought and water scarcity. Moreover, intensive catchment treatment that includes systematic use of all road-water harvesting opportunities can bring sedimentation under.

The second principle for water harvesting is to slow down runoff by guiding water to level land and spreading it. Water runoff loses its erosive nature at slower speeds, and sediments can settle. Reducing the speed of runoff also enables water infiltration to increase. Installing check dams, guiding water from steep slopes, building terraces and furrow ditches, and other techniques can be used to slow water runoff speeds. as more stormwater infiltrates the soil, less water must be managed as surface runoff.

Third, water users’ needs should be the central concern in water harvesting. The priorities of roadside users need to be discussed during the planning, design, and implementation stages of water-harvesting projects. These discussions must take into consideration all possible alternative water-harvesting mechanisms and the purposes to which the harvested water will be put. an example of water harvesting use is shown in the below picture (photo 4.2). for instance, gender is

PHOTO 4.2

Fodder grown from road culvert water, South Gondar, Ethiopia

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