Image caption Irrigation accounts for the vast majority of global freshwater consumption

An international standard on water reduction has been launched in an effort to encourage businesses to use water more sustainably.

The UK's Carbon Trust, which developed the scheme, said many business leaders did not see the issue as a priority.

The Water Standard will require firms to measure water use and demonstrate efforts taken to reduce consumption.

It is estimated that more than 60% of Europe's largest cities consume water faster than it can be replenished.

UN data shows that 70% of global freshwater use is for irrigation, 22% is used by industry and 8% is used in homes.

Water use is forecast to increase in developing nations by 50% by 2025 and by 18% in developed nations.

"We know that most businesses that are very big users of water don't really have a handle on [water stewardship]," explained Carbon Trust chief executive Tom Delay.

"Very few measure it, even fewer have targets to reduce consumption. So even if there is not a significant cost penalty for water use, there is a very significant business risk."

In order to be awarded the Carbon Trust Water standard, Mr Delay said the process was "relatively straightforward".

Image caption The Carbon Trust said that there was no global standard for business water reduction

"They need to be able to show us that on a year-on-year basis they are reducing their water use," he told BBC News.

"We look at the various water supply methods: mains, surface water abstraction, groundwater and rainwater collection.

"All of the water than comes into the company we will count as an input. We will also look at trade effluent because it is the dirty water and normally needs to be licensed and manage very carefully.

"We are looking for companies that are awarded the Standard to show a year-on-year reduction on both water input and effluent."

The Trust decided to branch out from its usual territory of measuring energy use and carbon footprints because there was not a global standard on water reduction, he added.

"We firmly believe that if you measure something and if you manage it, then you will reduce it and improve its performance.

But, he said: "We are not covering every single angle of water stewardship in this standard [but] we are saying that if you can reduce that then that is moving in the right direction."

Mr Delay explained that the issue of water scarcity was closely linked to climate change because "one of the big impacts will be the threat to freshwater supplies".

'Early adopters'

Among the four "early adopters" of the standard was Coca-Cola, whose operations in India had been criticised by campaigners who said the firm was abstracting too much water, which was having a detrimental impact on surrounding farmland.

Mr Delay said that the Trust's standard had been awarded to Coca-Cola Enterprises, which was responsible for the northern European operations of the global brand.

But he added: "The more people get into managing their water use, the more they will be exposed these sorts of questions and, hopefully, come up with some solutions."

On the website for the Coca-Cola Great Britain, which is a separate company to the Enterprises operation, it said: "We believe we can be part of the solution to India's water issues and we've made water stewardship the primary focus of our sustainability efforts throughout the country.

"We've improved our water use efficiency by 14% since 2004 and we're continuing to invest in new innovations and plant processes to help us make even more improvements moving forward."

Commenting on the launch of the Water Standard, Coca-Cola Enterprises chairman and chief executive John Brock described water as "fundamental to our business and our communities".

"By measuring and managing our water impact... we can address longer-term water scarcity issues," he said.

"This certification recognises the progress we have made towards becoming a water-sustainable operation."