To deal with water management challenges, it is important to bring a balance between both water supply and demand side. This can be done by employing strategies to increase water efficiency and water conservation. Water conservation strategies for the Middle East include reducing the use of potable water where possible, find alternative source of water for various water usage and increase the water efficiency of fixtures and equipment.
Efficient strategies along with water monitoring that tracks water consumption and identifies problems can significantly reduce both indoor and outdoor water consumption in water-scarce Middle East countries like UAE, Qatar, Kuwait and Saudi Arabia.
Most of the water conservation strategies have no additional cost implication and/or provide rapid payback while other strategies such as wastewater treatment systems and greywater plumbing system often require substantial investment.
1. Reduce Indoor Potable Water Consumption
Consumption of potable water in indoor uses can be reduced by installing water-efficient low flow fixtures for water closets, urinals, lavatories, showers, kitchen sinks and by using non potable water for flush functions.
The sources of non-potable water are mainly captured rainwater, greywater, municipal treated sewerage effluent (TSE) or reclaimed water. Waterless urinals are available in the market, which can be used in commercial buildings. Flow restrictors, electronic controls and compositing toilets can also help in achieving indoor water reduction targets.
2. Reduce Outdoor Potable Water Use
Landscape irrigation consumes huge amount of potable water. The water use for outdoor landscaping can be reduced significantly through an integrated approach. This includes employing combination of water-efficient irrigation technology, mulching, reduced turf or no turf grasses, using non-potable or recycled water, installing sub-meters to track and log irrigation trend and choosing native and adapted plant species in landscape design and using xeriscaping methods.
High performance water-efficient irrigation systems such as drip irrigation, bubbler distribution systems, scheduled irrigation and weather-based irrigation controlled can be used to increase the water efficiency.
3. Reduction in Process Water Use
The typical building systems that use process water include cooling towers, boilers, chillers, dishwashers and washing machines. The volumes of water used in these systems are quite significant.
The strategies to reduce process water use include; use of non-potable water such as rainwater, greywater or TSE in building processes and systems such as cooling towers. Metering of process water system can be done to collect information on water consumption and to identify leaks.
4. Recovery and Reuse of Condensate Water
Condensate produced from air conditioning equipment can be recovered and reused within the building. The condensate can be collected by installing a collection pan and then transferred to different systems through drainage pipes for various reuse purposes such as irrigation, toilet flushing, or other onsite purposes where it will not come in contact with the human body.
For buildings with a cooling load equal to or greater than 350 kilowatt, a large volume of condensate can be recovered and reused.