Chapter 3: Development of a Dynamic Water Budget Model for Abu Dhabi
3.1 Study Area
The planned study site is Abu Dhabi, the largest of the UAE's seven emirates, with a total area of 67,340 km2 and a desert climate. As seen in Figure 2, it is divided into three regions: Abu Dhabi, Al-Ain, and Western. The emirate is bordered on the east by Oman, on the south and west by Saudi Arabia, and on the north by the Arabian (Persian) Gulf. During the majority of the months, the climate is arid, with a hot and humid atmosphere. During the summer months of April to September, the mean temperature averages above 40°C (104°F). Abu Dhabi has a 600-kilometer-long coastline, which results in humid climatic conditions owing to the sun's heat. The months of October to March are relatively cool. The coldest months are January and February. Due to the emirate's lack of rainfall, natural recharge into groundwater is very poor, at about 40 MCM/yr (Environment Agency - Abu Dhabi, 2009a), adding to the emirate's water issues.
Figure 2: Proposed site of the study, the EAD (Western, Abu Dhabi and Al Ain regions)
Water demand in the EAD has risen dramatically in recent decades, with population growth and economic development serving as the primary drivers. The population of Abu Dhabi Emirate has increased many times in the last few decades, driving much of the increase in water consumption in the Emirate, especially residential, industrial, and municipal consumption (Statistics Centre - Abu Dhabi, 2015). The overall population has increased by more than 6.6 times since 1975 (Statistics Centre - Abu Dhabi, 2015). Water demand for agriculture, human use, and industrial activities has also risen as a result of shifts in lifestyle. Several government policies exacerbated the rise in water demand. Few of these policies promote agricultural growth in order to preserve rural heritage and reduce the EAD's reliance on imported produce. Some proposals advocate for desert greening in order to provide shelter for wild animals and to keep sand from accumulating along highways. A few advocate for the creation of public parks to improve the aesthetic appeal of open areas, while others advocate for the construction of residential and industrial megaprojects
to meet the needs of the local community as well as the growing tourism industry. The government's diversification vision of conversion into non-oil sectors is a major driver of industrialization.
Water is supplied from a variety of sources, including groundwater, seawater desalination, recycled sewage, and rainfall runoff. Based on the types of demands they can meet; they can be classified as potable (pot) or non-potable (np) sources.
Residential, industrial, municipal, and commercial are four of the seven demand sectors listed in EAD that are considered potable. These sectors need high-quality fresh water. Desalinated water is the only way to satisfy all four potable sector water demands. Desalination plants are located in the EAD in various strategic locations.
Groundwater, on the other hand, is the primary source for the three non-potable sectors of agriculture, forestry, and amenities. Non-potable demand is partially supported by TS and surface runoff. TS is only used to meet the needs of the forestry and amenities.
TS is a non-conventional source of water produced by treating wastewater to reusable quality. In EAD, there are wastewater treatment plants at all key population centers to produce and distribute TS.
The annual rainfall in the EAD is normally less than 100 mm (Environment Agency - Abu Dhabi, 2009a). As a result, rainfall and drainage are scarce water supplies in the region. There is very little information On Abu Dhabi's surface runoff.
The landscape is mostly flat, with sandy soil, sparse dunes, and a few low-elevation sabkhas (flat area with salt deposits). As a result, very little runoff is generated.
Rainfall creates drainage in the east of the EAD, which floods into the wadis (creeks) and flows westward, crossing into Abu Dhabi and supplying about 7.6 MCM annually
(Environment Agency - Abu Dhabi, 2014). Rainfall is measured using data from 24 stations spread around the EAD.
The EAD's overall water consumption in 2011 was about 3416 MCM, indicating a large rise in demand (Statistics Centre - Abu Dhabi, 2012). Population growth and economic prosperity are the major drivers of this rise. Much of the water consumption in Abu Dhabi Emirate has increased as a result of population growth, especially in the residential, industrial, and municipal sectors. The estimated population in 1975 was 211,812, and by 2005 it had risen to 1,399,484, a 6-fold growth in 30 years (Statistics Centre - Abu Dhabi, 2015). In the nine years since, the population of Abu Dhabi has doubled, reaching 2,656,448 in mid-2014 (Statistics Centre - Abu Dhabi, 2018). The average annual population growth trend from 2005 to 2014 was 7.6%. 507,479 Emirati inhabitants make up 19.1% of the total population, while the remaining 80.9% are non-citizens. Males account for more than 66.5% of the workforce, owing to an influx of male migrant workers (Statistics Centre - Abu Dhabi, 2018). The birth rate in the Emirate of Abu Dhabi is higher than in most developing countries, and the mortality rate is low. In 2014, the approximate crude birth and death rates were 14.3 and 1.2 per 1000 people, respectively (Statistics Centre - Abu Dhabi, 2018), reflecting the population's high net growth rates. In 2014, the population density of the Emirate of Abu Dhabi was 44.7 people per square kilometer.
The population density in the Abu Dhabi Emirate's three regions (Abu Dhabi, Al Ain, and Western) is 148.9, 52.6, and 8.9 people per square kilometer, respectively, representing the different levels of urbanization (Statistics Centre - Abu Dhabi, 2018).
Water demand for agriculture, human use, and industrial activities has also risen as a result of shifts in lifestyle. The growth in water demand was exacerbated by
a number of public policies. For example, expansion of agriculture to protect rural heritage and reduce dependency on imported food.