The water levels of the Zamzam Well were previously monitored by a simple drum hydrograph. At present, this device has been replaced by a more sophisticated and multi-tasking digital control system, which accurately and continuously monitors the fluctuations of the water levels in the well and the electrical conductivities, total dissolved salts, pH, temperatures, and dissolved oxygen. The Center's specialists can easily communicate remotely with the monitoring device through the communication network and the web without the need for a specialist to be at the well site permanently. A network of more than 45 monitoring wells has also been installed along the Wadi Ibrahim to monitor the response of the entire aquifer system to the filling and re-filling of water. Some of these wells are fitted with automatic digital water level recorders.
With the steady annual increase in the number of visitors, including the Hajj and the Umra pilgrims, the demand for the Zamzam water has increased. Therefore, the primary task of the SGS, represented by the ZSRC, is to assess the safe well yield and recommend the necessary procedures, while working to reconcile the increase in demand in the future with the available water supply, so that the sustainable supply limits are not exceeded. This is done by monitoring the amount of water pumped from the well through sophisticated digital measuring devices installed in the external pipes of the well for the purpose of limiting the quantity extracted and checking the water balance of the Well.
One of the devices that monitor the water levels inside Zamzam Well.
Volume meter of the water extracted from the Zamzam Well.
One of the main tasks of the ZSRC is to continuously monitor the chemical and bacterial characteristics of the water inside the well and also within the distribution networks of the Zamzam water in The Grand Mosque and the Prophet's Mosque.
In doing so, weekly water samples are collected from the Zamzam Well and from various places inside The Grand Mosque and the Prophet's Mosque, including the thermoses, water coolers, filtration and sterilization stations, and storage sites. These samples are analyzed in the Central Laboratories of the SGS. Officials are also informed to take the necessary measures, if unexpected components are detected.
Sampling the Zamzam water from the thermoses in the Grand Mosque under the quality program.
The surface area of the outcrops and the alluvium of the Wadi Ibrahim covers only 45 km2. Limited re-filling or recharge of the Wadi alluvium aquifer occurs through the infiltration of storm water that fall directly on the Wadi surface. The urban development of Mecca has now extended over the Wadi bed, diminishing the already meager amount of storm water through infiltration into the underlying aquifer due to surface sealing and the channeling of storm water into the storm drainage systems.
In arid climates, such as in Saudi Arabia, where there is no permanent surface water, the natural recharge is limited to the occasional, brief storms and torrents. Water stocks can be severely affected during long dry periods or during times of increased groundwater withdrawal. To sustain the groundwater supply of the wells, the aquifers need to be continually recharged by the direct infiltration of storm water. Thus, modeling the aquifer recharge is crucial to ensure that supply and the demand for the Zamzam water is appropriately balanced. The ZSRC is, therefore, assessing and quantifying the effects of urbanization on the recharge and developing recommendations for the planning controls to guide the further development of the Wadi alluvium.
Mecca is unusual among Saudi Arabian cities because of its high proportion of relatively high-rise buildings, some of which date back to many decades. High-rise development continues to present a solution to urban expansion over the Wadi Ibrahim Basin area, but the deep foundations penetrating the aquifer can expose the groundwater to contamination and also restrict its movement. Strict building controls are, therefore, required in allowing high rise developments in sensitive areas, as indicated by near real-time maps and models of the water table elevations that are calculated from the data of monitoring wells and by the hazard assessments of the probable impacts on groundwater quality. The engineering geology maps of Mecca also help to highlight zones of hazards on the aquifer in the area.
Engineering geology map of the Al-Maisam area in Mecca.
The ZSRC works to present solutions to these complex and interrelated problems through a modern, integrated, and multi-faceted approach to water catchment management and conservation. Through such actions, the quality and quantity of water supply from the Zamzam Well can be sustained to meet the spiritual needs of the world’s one billion Muslims.
5- Storm drain management related to the recharge of the aquifer
Storm drains are designed specifically to prevent flooding by capturing storm water falling on rooftops, roads, and surrounding areas, and by rechanneling the water to flow into the wadis or into safe areas. The ZSRC has undertaken intensive modeling of the natural drainage patterns within the Wadi Ibrahim basin in order to define ways and means of harnessing storm water and produce maps showing the scarcity of groundwater inside the basin. It has also proposed several ways to design storm water channels for use as a groundwater supply.
Furthermore, the ZSRC's policy requires an integrated design of the storm water network for all modern projects with an area of more than 1,000 square meters within the boundaries of the Wadi Ibrahim basin. In addition, the ZSRC has produced maps on the levels of groundwater in the whole of Wadi Ibrahim, based on the results of the hydrogeological model of the basin. These maps should be taken into account when issuing permits for building construction within the Wadi Ibrahim basin.
6- Assessment of future activities and projects f and their impacts on the Zamzam Water
One of the ZSRC’s responsibilities is to study, assess, and quantify man-made activities that impacts on the groundwater environment and monitor future development projects. The ZSRC has provided many recommendations in various projects about foundation designs in order to prevent or mitigate their likely present or future effects on the groundwater supply in terms of quality, quantity, and groundwater flow.