UAE is a country with a hot desert climates, it only experiences two seasons, a long dry summer for most of the year and a mild winter for only 4 months (December to march). With such a climate, rainfall is sporadic. Abu Dhabi experiences rainfall averaging 12 cms per year because of its sub-tropical, arid climate. As for Dubai, rain falls only five days a year. 

Because of the hot weather, we mainly relay on fresh ground water agriculture and irrigation which is also becoming scarce because of human demands and increase in population. It is said that UAE may run out of groundwater by 2030. 

As awareness about water scarcity increases, more efficient methods are being used for irrigation. 

Those include:

• - Drip irrigation, one of the methods being used as an alternative to spray irrigation. Drip irrigation consists of perforated tubes placed along the floor, or buried near the roots of plants, which deposit water directly to the plant roots, it is the most water efficient method of irrigation for arid areas.
• - An irrigation system consisting of gravel and pipes 60cm below the surface. Before anything is planted, the plot is excavated and lined with a water-proof tarp followed by layers of gravel and dirt placed around a half pipe. The pipe is drilled at strategic areas in order to let water flow through but sand and soil stay out.

Other simple methods include:

• - Adjusting sprinklers so only the grass and plants are watered and not the streets and side walks. 
• - Watering during cooler times of the day such as in the morning or evening to avoid large amounts of evaporation.
• - Coordinating irrigation with seasonal rains.
• - Growing more drought-tolerant plants.

agriculture and related sectors consume about 72 per cent of the total water consumption in Abu Dhabi and Groundwater accounts for 94 per cent water consumption in the agriculture sector in the emirate, according Environment Agency of Abu Dhabi. With that in mind, in 2014, new irrigation systems in Abu Dhabi were implemented and they saved 46% water. 

The new irrigation systems, named, “inline pressure compensating dripline” and “adjustable inline drip system”. These systems continuously adjust to varying water pressure, ensuring a constant flow rate.

• - inline pressure compensating dripline, ensures that water will keep flowing to crops, whether it is being drawn from a well, pond, reservoir or canal, it also maximizes uniformity and water-use efficiency, even with elevation changes. Increase crop yield by reducing the use of water, chemicals, and fertilizer. It is engineered and tested to stand up to harsh chemicals, UV radiation and damage that can be caused by farm equipment
• - adjustable inline drip system ideal suited for irrigation of shorter plant rows with different water requirements. It allows an even water supply, independently of the water pressure. Through it the water quantity per plant can be exactly dosed, so that no water is wasted.

In 2016, HomeIQ, the UAE-based intelligent home company announced the launch of a self-programming smart irrigation systemthat helps conserve water and cuts garden watering bills by up to 60%, while keeping lawns lush and green. It can save up to 60% of water usage by customizing your garden's watering schedule to fit its needs, it uses moisture sensors and weather data to automatically water lawns and plants. 

Sources:

https://www.zawya.com/uae/en/companies/story/UAEs_HomeIQ_launches_smart_garden_irrigation_system_that_saves_up_to_60_of_water_launched_in_the_UAE-ZAWYA20161218102733/

https://www.ecomena.org/irrigation-systems-in-uae/

https://gulfnews.com/uae/environment/new-abu-dhabi-irrigation-system-saves-46-water-1.1338984