A hydrologic-economic model for sustainable water resources in the Gaza Strip, Palestine

With the goal of identifying deficiencies in water allocation and to demonstrate how the existing water supply might be integrated into the overall water supply system, a regional optimization model is developed for the Gaza Strip that includes explicit simulation of groundwater flow and the economics of domestic and agricultural water uses. This model considered management options of building desalination and wastewater treatment plants, tertiary treatment of wastewater, as well as allocating and transferring water between agricultural and urban sectors. Model results show several crucial outcomes: (1) groundwater use for agriculture cannot happen at the current level after 2020 without introducing a combination of new supplies from treated wastewater (TWW) and desalination; (2) an annual reduction of 2% agriculture would significantly reduce groundwater depletion; (3) the current reliance on agriculture could continue if the reuse of TWW, desalination, and tertiary treatment of wastewater are introduced; (4) introducing TWW for agriculture would drastically reduce the shadow value of water for all Gaza districts; (5) introducing desalination can increase vegetable cultivation, which is the most profitable crop per cubic meter of water; (6) desalination of seawater after considering TWW would reduce the shadow value of water below the desalination cost of US$0.60/m3; and (7) introducing tertiary treatment of TWW would further reduce the shadow value of water and increase availability of water to agricultural and municipal uses. Moreover, a sensitivity analysis shows that improved information considering parameter uncertainty would provide accurate prediction of infrastructure sizing and efficient allocating of water among competing users