Images taken over the Jebel Ali area, located on the southern outskirts of Dubai, capture the area before and after historic flooding. The top image was taken on 3 April and the bottom image on 19 April (Source: NASA).
Potential causes
There are many theories about the reasons behind these changing rainfall patterns.
According to scientists convened by the United Nations there is not enough data to reach conclusions about the effect of
climate change on rainfall trends in the Arabian Peninsula. However, we do know above-normal ocean temperatures can be
a contributory factor to heavy rainfall. El Niño and other natural weather cycles along with human-induced warming has
resulted in large parts of the Indian, Pacific and Atlantic Oceans being hotter than usual.
Cloud seeding is a technique that is particularly employed in drought prone regions to promote precipitation. It has been
used in the UAE since the 1990s and is managed by the National Centre of Meteorology (NCM) through its UAE Rain
Enhancement Programme (UAEREP). An article written by JBA Risk Management quotes Esraa Alnaqbi, a senior forecaster
at NCM, as attributing the exceptional rainfall in April 2024 to a low-pressure weather system, significantly amplified by
climate change factors.
Flooding and the aquifers
The UAE relies heavily on its aquifers as a crucial source of groundwater. These aquifers play a significant role in water
supply, supporting agricultural, industrial, and domestic needs. An aquifer is a body of porous rock or sediment saturated
with groundwater. Groundwater enters an aquifer as precipitation seeps through the soil.
In Dubai we there are coastal aquifers but there are five interconnected mechanisms that can cause them to flood when
there is heavier than normal rainfall:
1. Surface runoff and infiltration: during heavy rainfall, the excess water that cannot be absorbed by the soil becomes
surface runoff. In coastal areas, the flat terrain often leads to slower drainage, allowing more water to accumulate on
the surface. This water can infiltrate the aquifer, raising the groundwater levels. If the aquifer is already near its capacity,
additional infiltration can cause the water table to rise above the ground surface, leading
to flooding.
2. Limited drainage capacity: coastal aquifers often have limited natural drainage due to their proximity to sea level and the presence of impermeable soil layers. Heavy rainfall can overwhelm the natural drainage systems, causing water to pool and
increasing the likelihood of flooding. This is particularly problematic in urbanised coastal areas where impermeable surfaces
(like concrete) prevent water absorption and exacerbate runoff.
3. High tide and storm surges:when heavy rainfall coincides with high tide or storm surges, the drainage of excess
rainwater into the sea is impeded. This can cause a backflow effect, where seawater pushes into the coastal aquifer and
exacerbates flooding from the landward side.
4. Urbanisation and land use: urbanisation in coastal areas typically reduces the natural land available for water infiltration,leading to greater volumes of runoff. The construction of buildings, roads, and other infrastructure increases surface runoff,which can overwhelm drainage systems and lead to localised flooding. Urban planning that does not adequately account for water management can exacerbate these effects.
Mitigating flood risks
Rapid urbanisation and weak, insufficient and badly maintained drainage systems have certainly play a part in exacerbating
the flooding. Effective water management strategies, including improved drainage systems and sustainable urban planning,
are essential to manage the impacts on coastal aquifers and mitigate flood risks. It’s something the Dubai Government is
taking this seriously with substantial investment to combat flooding, such as the construction of the Deep Tunnel Storm
Water System that cost around USD2.5 billion.
Businesses and individuals, also, need to take more notice of this increased risk especially as insurers have begun to impose
significant policy deductibles for those premises that present higher flood risks. Having managed hundreds of claims
caused by these rainfall events, from those involving high-value residential properties through to commercial premises
including manufacturing plants, warehouses, hotels and shopping malls, we can offer five tips:
1. Keep buildings maintained and ensure that roofs and other water proofing systems will protect against extreme
precipitation events. We’ve seen numerous incidents that could have been avoided through regular maintenance and
upgrading water proofing systems.
2. Ensure that sewers and wastewater drains within your property are kept free of silting and blockages. Make sure that your property has adequate drainage to prevent build-up of water. You can’t avoid damage caused by overloading of the main
drainage systems but quite often better drainage around your own property can make the difference.
3. Stillage warranties that specify keeping goods on pallets so that they are above ground level have been found to be
inadequate. If your property has previously flooded or is in a high-risk area then consider storing goods above ground level
to help protect them from flood damage.
4. Update business continuity plans so that they specifically consider flooding and how you can get mitigate damage and
get your business up and running as quickly as possible. Think about: a) access to equipment such as dehumidifiers that are used to dry out properties. There can be substantial pressure on their availability after a large flood; b) what happens if you cannot access your property for a short period - is there any way that you can keep trading to reduce the impact and business interruption losses?; c) who has responsibility for tracking potential severe weather events and the actions you need to take to reduce the risk of loss, such as moving furniture above the ground floor level if that is possible.
5. If your premises is in an area exposed to potential flood risks then it may be worth investigating flood defence systems, such as flood doors, flood barriers or bund walls. They can help reduce insurance cost, alleviate the need for higher
deductibles and avoid unnecessary interruptions to your business.
When a loss does occur a quick loss adjuster response can make a real difference. We always seek to get site access without delay so that we can help mitigate the loss and formulate plans to repair the damage and get the business up and running as quickly as possible. Technology such as drones can help when flooding prevents access to the premises and is certainly something we have used to good effect.
For more information please get in touch with Matthew Blaikie, Director, United Arab Emirates mblaikie@advantaglobal.com