Water saving is a key element in a new contest launched by educational publisher Reed Elsevier.

The competition promises a five-figure payout for the winner for finding the best way to ensure safe supplies of water in places where the valuable commodity is currently insecure.

Five aspects must also be demonstrated in the winning design, including sustainability and the potential for replication of the suggested solution.

Practical applicability is preferred, along with an in-built equality of supply for all people, without discrimination.

Local communities should be engaged in the initiative, along with stakeholders, according to the organiser.

The competition is part of Water for Life Decade, which began in 2005 and is due to last until 2015.

Run by the UN, the decade-long awareness scheme highlights the need for water saving, as the amount of the liquid consumed has increased at more than twice the rate of population growth in the last 100 years.