With almost a third of the world’s land surface characterised by a severe lack of available water and that percentage set to increase, a new report by Arup is calling on global cities to adopt 21st century innovative measures in a bid to ensure they remain habitable to residents.

The Cities Alive: Rethinking Cities in Arid Environments report outlines three key principles in shaping city-building in arid regions for the 21st century. It highlights developments around the world, such as industrial-scale fog and dew harvesting and cooling pavements that can reduce ambient temperatures by up to seven degrees in areas that continue to become drier.

The authors of the report say that investment in green and blue infrastructure is crucial to increase the resilience of arid cities. Project leaders also need to be more aware and factor in the demands of the climate whenever decisions on made for design intelligent buildings and public spaces.

Examples of initiatives in arid cities that are making them more sustainable:

• Fog and dew harvesting: new technology is allowing harvesting systems and materials to be optimised to extract large amounts of water, even in arid environments with low levels of humidity.
• Cool pavements: small changes to existing designs can make an impact. For example, a rethink of public spaces could improve the quality of lives for citizens. The city authority in Los Angeles has begun coating its streets with a special paint, CoolSeal, to reduce the temperature of the city.
• Energy efficient buildings: buildings can be designed to play an active role in reducing reliance on air conditioning and mitigating the Urban Heat Island effect.  The Al Bahar Towers in Abu Dhabi have a unique dynamic shading system – a modular ‘Mashrabiya’ that opens and closes to provide self-shading as the sun moves around the building.
• Green roofs and walls: Not just beautiful but provide cities with greater resilience. A Xeriscape approach, using plant species can maximise effective shade and shelter, reducing noise, glare, dust and air pollution.
• Open air living: Attractive and comfortable public spaces are vital to the success of cities, significantly impacting their social and economic success.

Hrvoje Cindric, Middle East urbanism leader at Arup, said: “Cities in arid regions are expected to experience the highest rates of natural population growth and urbanisation in the coming century. Yet most are still being planned and designed based on a global city-making paradigm from the 1950s. Cities need to adapt strategies that combine technological innovation with locally adapted and climatically appropriate solutions. Even simple things such as building orientation and the resulting shade can have a significant impact – allowing people to socialise outdoors, rather than rushing from car to building. Rethinking the way we design public space, can have a significant impact on the wellbeing of citizens.”

To download the report in full, click here.