Zamzam Well - Technical Information

Technical Information

The Zamzam well was excavated by hand, and is about 30 m (98 ft) deep and 1.08 to 2.66 m (3 ft 7 in to 8 ft 9 in) in diameter. It taps groundwater from the wadi alluvium and some from the bedrock. Originally water from the well was drawn via ropes and buckets, but today the well itself is in a basement room where it can be seen behind glass panels (visitors are not allowed to enter). Electric pumps draw the water, which is available throughout the Masjid al-Haram via water fountains and dispensing containers near the Tawaf area.

Hydrogeologically, the well is in the Wadi Ibrahim (Valley of Abraham). The upper half of the well is in the sandy alluvium of the valley, lined with stone masonry except for the top 1-metre (3 ft 3 in) which has a concrete "collar". The lower half is in the bedrock. Between the alluvium and the bedrock is a 1⁄₂-metre (1 ft 8 in) section of permeable weathered rock, lined with stone, and it is this section that provides the main water entry into the well. Water in the well comes from absorbed rainfall in the Wadi Ibrahim, as well as run-off from the local hills. Since the area has become more and more settled, water from absorbed rainfall on the Wadi Ibrahim has decreased.

The Saudi Geological Survey has a "Zamzam Studies and Research Centre" which analyses the technical properties of the well in detail. Water levels were monitored by hydrograph, which in more recent times has changed to a digital monitoring system that tracks the water level, electric conductivity, pH, Eh, and temperature. All of this information is made continuously available via the Internet. Other wells throughout the valley have also been established, some with digital recorders, to monitor the response of the local aquifer system.

The water level is 3.23 m (10.6 ft) below the surface. A pumping test at 8,000 litres per second (280 cu ft/s) for more than a 24 hour period showed a drop in water level from 3.23 m (10.6 ft) below surface to 12.72 m (41.7 ft) and then to 13.39 m (43.9 ft), after which the water level stopped receding. When pumping stopped, the water level recovered to 3.9 m (13 ft) below surface only 11 minutes later. This data shows that the aquifer feeding the well seems to recharge from rock fractures in neighbouring mountains around Mecca.

Zamzam water has no colour or smell, but it has a distinct taste, and its pH is 7.9–8.0, indicating that it is alkaline to some extent and is similar to seawater.

Minerals Mass concentration as reported by researchers at King Saud University.

• Sodium 133 mg/L (4.8×10−6 lb/cu in)
• Calcium 96 mg/L (3.5×10−6 lb/cu in)
• Magnesium 38.88 mg/L (1.405×10−6 lb/cu in)
• Potassium 43.3 mg/L (1.56×10−6 lb/cu in)
• Bicarbonate 195.4 mg/L (7.06×10−6 lb/cu in)
• Chloride 163.3 mg/L (5.90×10−6 lb/cu in)
• Fluoride 0.72 mg/L (2.6×10−8 lb/cu in)
• Nitrate 124.8 mg/L (4.51×10−6 lb/cu in)
• Sulfate 124.0 mg/L (4.48×10−6 lb/cu in)
• pH 8
• Total dissolve alkalinity 835 mg/L (3.02×10−5 lb/cu in)