Conserving river ecosystems with less water - A key challenge for sustainable development

Abstract

In 2013, Chile established new legislation capping the allowable environmental flow in a river at 20% of mean annual flow. This move to legally limit maximal environmental water allocations is unprecedented, but the allocation of small percentages of river flow to the environment is common practice. Whether expressed as 10-20% of mean annual flow, Q95 or 7Q10, legislated environmental water allocations (environmental flows) are nearly uniformly small relative to the levels indicated by ecologists as necessary for maintaining healthy aquatic ecosystems.