Unconventional Water Resources

A global initiative by UNU-INWEH to inform future policy and investment decisions on innovative water resources management

The Challenge

While SDG 6 calls for access to safe water and sanitation for all by 2030, more than two-thirds of the global population is expected to face water scarcity by the end of SDG era. The commonly used conventional water resources, such as rainwater or river runoff, will not be sufficient to meet the growing demand for water in water scarce areas. Increasing global water scarcity under changing climate and rainfall patterns may further impact water resources availability in dry areas.
 

The Solution

The limitation of conventional water resources to meet future needs amid changing climate calls for a sharper focus on advocacy, research, practice, and planning; and a paradigm shift to include ‘unconventional water resources’ and technologies in current and future water management strategies. Unconventional water resources are those that are generated as a by-product of specialized processes such as desalination; or that need suitable pre-use treatment; or pertinent on-farm management when used for irrigation; or need a special technology to collect/access water. Examples of these water resources include:

• Desalinated seawater and highly brackish groundwater;
• Groundwater in regions with no culture or experience in its large-scale use and groundwater confined in deep geological formations or in off-shore aquifers;
• Physical transportation of water through tankers and icebergs;
• Micro-scale capture of rainwater where it otherwise evaporates;
• Atmospheric moisture harvesting such as cloud seeding, fog water collection;
• Collection and treatment of wastewater, grey water, and storm water; and
• Collection and use of agricultural drainage water.

The first five types of unconventional water resources listed above can be considered ‘new water’ and the remaining two ‘used water’.