Spatial and temporal trends in groundwater salinity in Bahrain

Abstract EN

In Bahrain, groundwater in the Dammam aquifer is ^e only natural source of fresh water to meet ^e county's increasing water demands.

Prolonged over-exploitation of the aquifer has led to continuous water level decline, reversal of hydraulic gradients between ^e relatively fresh¬water aquifer and adjacent brackish- and saline- water bodies, and their encroachment and salinization of the aquifer.

In this study, a countrywide potentiometry and salinity survey has been conducted in the year 2001/2002 to investigate the aquifer deterioration process.

Spatial analysis of the aquifer state variables indicated that most of the potentiometric surface of the Dammam aquifer has declined to below sea level, and the quality of the aquifer recharge water, received from eastern Saudi Arabia, has been significantly influenced by inland mixing with higher concentration waters, mainly seawater and underlying brackish water.

Furthermore, temporal changes in the aquifer's state variables over the period 1992-2002 are examined using salinity and potentiomet^ data from a previous survey.

Temporal analysis indicated a general water level decline, and that the salinity in most of the aquifer areas has exhibited an increase by about 30%, and the deterioration process has become more widespread over the assessment period.

Analysis of the spatial and temporal changes of the Dammam aquifer indicated that management schemes and efforts undertaken in the last 10 years by the water authorities have not been effective in modifying the aquifer's conditions, and that unless the current levels of abstraction from the aquifer are brought back closer to the level of renewable recharge, groundwater quality would be completely ruined.

In order to have significant reduction in groundwater abstraction rates, it is suggested that a shift towards demand-side interventions is made, such as employing the economic incentive of groundwater pricing.