The integrated hydrologic modeling as a key for sustainable urban water planning in the Gaza Strip

Tamer Eshtawi, Mariele Evers, Bernhard Tischbein

Thursday 2 july 2015

11:30 - 11:45h at Oceania Foyer (level 0)

Themes: (T) Water resources and hydro informatics (WRHI), (ST) Surface and subsurface flow interactions

Parallel session: 11L. Water resources - Flow interactions

This study demonstrates the strength of using integrated hydrologic modeling in the sustainable urban water planning process. It provides a holistic view of the urban water ecosystem of the Gaza Strip, quantifies the urban water budget interaction with sufficient spatial and temporal details, and supports realistic scenarios inferred from the decision making agenda. A coupling of the surface water (SWAT), the groundwater (MODFLOW) and the solute transport (MT3DMS package) models was performed to quantify surface-groundwater and quantity-quality interactions due to the impacts of urban area expansion. The results indicate a good fit between measured and simulated nitrate and chloride concentrations. The responses of the groundwater level, the nitrate concentrations (related to human activities) and the chloride concentrations (related to seawater intrusion) to urban area expansion and corresponding changes in urban water budget were examined on a macro scale level. The potentials of non-conventional water resources scenarios, namely desalination, stormwater harvesting and treated wastewater reuse as well as an infrastructure performance scenario were investigated. In a novel analysis, the opportunity for groundwater improvement and deterioration under each scenario were articulated and discussed in spatial-temporal and statistical approaches. The quality deterioration cycle index was estimated as the ratio between the amounts of low and high quality recharge components within the urban water ecosystem that predicted of year 2030. The spatial sustainability index for the groundwater quantity (SIQ) and the spatial sustainability index for the groundwater quality (SIC) were developed for the targeted scenarios as measures of their effectiveness toward sustainable groundwater.