Model Investigations on the Groundwater System in Jordan – A Contribution to the Resources Management (National Water Master Plan)

Summary

In Jordan, groundwater is one of the major water resources and depends strongly on the regularity of the seasonal precipitation. Although there is a considerable annual precipitation its contribution to the groundwater recharge is limited in time and quantity. Precipitation is highly variable and drought periods occur frequently. Therefore, climate changes and the future groundwater development are of vital interest for this country under semi-arid to widely arid weather conditions.

In fact, Jordan faces a critical water shortage, and the groundwater system is over-exploited since many years. A high population growth rate and the concentration of population in the urban centres of the northern part of Jordan lead to a deterioration of the situation. Consequently, there is an urgent need of countrywide regulations, including the establishment of sustainable groundwater production and protection schemes as an integrated part of the National Water Master Plan (NWMP), as prepared by the Ministry of Water and Irrigation in Amman.

As a contribution to the National Water Master Plan the comprehensive numerical simulation model for Jordan has been established in order to provide a tool for the groundwater resources management. The countrywide simulation model of this complex groundwater system covers an area of about 100,000 km2. It includes the major hydrogeological formations, which are composed either of basalt, marl, limestone, or sandstone. Due to hydrogeological and hydraulic reasons and with respect to plausible hydraulic model boundaries, some parts of Saudi Arabia (e.g. the entire Wadi Sirhan area) are included, whereas in Jordan the Wadi Araba and the Jordan-Valley have not been incorporated.

The regional development of the groundwater system during the past three decades has been simulated. So far, two long-term scenarios until 2050 have been calculated by assuming that either the recent groundwater production will continue or that the future groundwater production will be modified in accordance to projections taken from the National Water Master Plan, respectively. Applied for prognosis purposes the model delivers figures about possible future changes in groundwater flow and quantity.