Modelling groundwater aquifer to estimate water sustainability in Sana’a basin / Izzadin Ali Ahmed Al-Shaez

Escalating water scarcity threatens global sustainable development. Water
scarce regions will increase worldwide during the current century, as the
water demand rate is more than twice the population growth rate. Yemen
has one of the fast growing population rates in the world and is facing
high water stress. Sana’a city, in particular, is experiencing a critical water
shortage due to industrialisation, urbanisation and fast population growth
rate. The water table at Sana’a aquifer, which is a groundwater-dependent
city, has dropped significantly since 1972, as new technology was introduced
to extract groundwater. Some studies estimated that Sana’a city would be
the first metropolitan area to run dry during the coming few decades due
to unsustainable groundwater pumping, as many wells will be depleted.
This dissertation’s main aim is to evaluate the impact of climate change on
groundwater resource in the Sana’a basin aquifer. To achieve the objectives
of the study, firstly, the total groundwater recharge amount and spatial
distribution were estimated using chloride mass balance. Selected wells and
locations were chosen to collect groundwater and rainfall samples. In total,
22 sites spread all over the basin were chosen and the samples were collected
during the two rain seasons from March-May and July-August in the year
2014. Likewise, 22 wells covering all the basin area were chosen to take
groundwater samples for the chloride concentration test. The samples were
taken during the rain season from March-May and July-August in 2014.
After that, a chloride content analysis was carried out in the laboratory. The
samples were collected and transported according to the standard procedure
under the chemistry laboratory specified conditions. The results indicate that
the overall recharge rate is almost 6.3% of the annual rainfall.