Water harvesting: Groundwater storage reservoir in Wadi Ishe, Jordan

Wadi Ishe pilot project is a trial project set to illustrate the recharge of runoff and storage in an artificial groundwater reservoir to minimize evaporation losses and as a substitute of water supply for rural arid areas that could be used for stock watering and some agricultural activities. The HEC-Hydrologic modeling System was used to estimate the runoff potential. The model in the research will provide possibilities for the simulation of precipitation-runoff procedures. The hydrographs shows a 10 years return period with a total yearly precipitation of 44 mm and total loss of 35.3 mm gave a total runoff of 8.7 mm. The total precipitation volume for the years 2000-2010 within the catchment area was approximately 36.14 Mm³. Designed to intercept the groundwater flow in connection with a flood in the Wadi Ishe basin, an underground dam was constructed from the base of the wadi channel all the way up to the surface (about 3 m height). A well was incorporated upstream of the barrier to extract the stored water from the underground reservoir. The porosity of the refilled reservoir test section was calculated to be 20-23%. The annual storage of the subsurface reservoir is approximately around 300 m³/year, where there is an average of 5 annual rain events in that area. In the catchment area another 11 potential sites were identified using the site selection criteria that was developed. Those sites once implemented using this technique would make a clear difference in water availability and enhance development around Wadi Madoneh. With this study the in different regions of the world already applied technique of groundwater dams could be first time also effectively implemented in small arid wadi catchments by using an adapted improved new technology by combining harvesting and artificial recharge effects. Key words: Groundwater reservoir, Jordan, rainfall-runoff model, surface runoff Wadi Ishe, water harvesting.