Salinity and pumping relations in Fazael- Jericho well fields and determining of utilization thresholds Dr. Joseph Guttman Hydrologic Science Workshop – Study of the Eastern Basin of the Mountain Aquifer Jerusalem, Ambassador Hotel June 16-17, 2013
The source of the fresh water is from rainfall recharging the aquifer along the mountain crest Inside the JRV there are brines. The outlet is through springs that flow into the Dead Sea and lateral flow into deep formations within the Rift Valley. The fresh water is limited. In some wells, increasing of the pumping is accompanied with salinity rising. This constrain limited the possibilities to increase the pumping of the fresh water. Nevertheless, substantial volumes of freshwater are lost in the Rift Valley and become saline. Future development critically depends on rational operation of the current resources and finding and developing of new local sources (freshwater, brackish and effluent). General situation Dead Sea
Sectionalization of the Eastern Basin
Water level map
Water level hydrograph
Salinity behavior in some wells The wells are located along the foothill and capturing the fresh water before it mix with the saline body
Location of Fazael wells
Geology- The monocline (flexure) along the foothill Flexure
The wells and the flexure in Fazael well field
Water level and Salinity
Correlation between pumping and salinity Well: Fazael 6 Reduction in the monthly and yearly amount reduce the salinity in the well
Jericho Uja wells
Salinity in Jericho wells
Jericho 2-Pumping and salinity
Jericho 5-Pumping and salinity
Fresh and Saline end members Two end-members. Most of the fresh water wells are located on this mixing line
Salinization Sources Inside the rift there are salt domes. They are the source of the salinization of the regional karstic aquifer Fresh Water Brine
Determining of the Red Line (Utilization thresholds) Salinity is the main parameter that affecting the water supply. Because each well in the region has a different salinity pattern, it becomes quite difficult (if not impossible) to predict the salinity in each well. Our assumption is that the different salinity pattern is a result of combination between several causes: – Geology: The geological location of the well, the quality and thickness of the aquifer layers. – Hydrology: Natural recharge, Hourly discharge, Specific discharge (dynamic drawdown), water level, the location of the fresh-saline (dynamic) interface. – Technical: Location and length of the perforated section. – Demand: Monthly and yearly pumping in a single well and in the neighbouring wells. The weight of each factor may vary among different wells.
Recommendation RemarksYearly pumping Recommended Monthly pumping Recommended Hourly Discharge Yearly pumping 2012 Name Fazael Fazael 3 Sensitive to salinization Fazael Fazael Fazael 9 Practically, utilization thresholds ("red lines") should define for each borehole by trial and error. Without determining precise criteria for each borehole, the deterioration of groundwater quality and quantity will have impacts on the future development and on the local economy.
Summary and Conclusion The water supply base on local resources only. Fresh water is a limited resource and is effected by salinization process. Wells are located at the wadis apertures few hundred meter west to the flexure (eastern edge of the foothill) in order to capture the fresh water before it enter to the saline water. The salinity is the main parameter that effect on the supply. It is essential to maintain the salinity at a low and stable value. Because each well has a different salinity pattern, it becomes quite difficult (impossible) to predict the salinity trend in each well and to predefine precise regional utilization thresholds ("red lines").