Reconciling Per-Capita Water Metrics with Aquifer Stress on Qeshm Island: Pathways for Coastal Blue Economy Development

Qeshm Island’s extreme aridity and rapid growth expose a mismatch between headline per-capita renewable water figures and actual aquifer stress. Using multi-decadal precipitation, census, and well records, we estimate renewable supply, recharge, storage, and salinity. Natural replenishment is minimal: about ۶۰% of rainfall is lost to evaporation and most of the remainder leaves as runoff, yielding little effective recharge. Under trend-based demographic projections, renewable water per capita declines to ۷۵۷ m۳ per person per year by ۲۰۳۶ (medium evaporation-loss scenario). Groundwater observations show a long-term water-table decline near ۰.۰۹۱ m per year and salinity rising to about ۱۴ to ۱۶.۶ dS/m, consistent with persistent overdraft and seawater intrusion or up-coning. To translate hydrologic limits into development choices, we evaluate a conservative ۴۰% withdrawal of renewable yield with a mixed allocation ۷۰% agriculture, ۲۰% industry, ۱۰% domestic. At this intensity the budget can irrigate about ۱,۵۲۳ ha of date palms, support roughly ۳۳۵,۰۰۰ t/yr of petrochemical output, and supply about ۲۳,۸۴۱ residents, generating approximately ۱۶.۴۵ million (agriculture), ۳۳۴.۶۹ million (industry), and ۰.۲۲ million (domestic) per year around ۳۵۱ million in total. These results show that per-capita indicators alone can overstate security; resilient coastal-marine development on Qeshm will require aligning withdrawals with limited renewability and storage, coupled with managed aquifer recharge, targeted desalination, and selective use of saline groundwater to protect potable supplies and industrial applications requiring low-salinity makeup water (e.g., boiler and cooling systems), where acceptable conductivity is typically ≲۰.۲–۲ dS m⁻¹ with low hardness and silica.

کلیدواژه ها:

Groundwater Overdraft ، Qeshm Island Aquifer ، Renewable Water per Capita (RWRPC) ، Salinization ، Water Scarcity Management