We use cookies to imporve your experience. By using our site, you consent to our cookie policy Learn more
arrow arrow_up breadcrumb-chevron-right breadcrumb-home dropdown-arrow-down loader GALogoWUNEP GALogo2018 GALogo2019 menu read-more-plus rrss-email rrss-facebook rrss-flickr rrss-instagram rrss-linkedin rrss-twitter rrss-vimeo rrss-youtube rrss_google_plus rrss_skype rrss_web pdf search share Completed In Process Ideas In Develpment Toogle Toogle Thumbnail View List View play close filter-collapse filter edit media_photo_library media_video_library graphics pictures videos collections next

Evolving Roles of Blue, Green, and Grey Water in Agriculture

03 Apr 2019

Due to its multiple uses, water is a highly competed‐for resource. While the competition is mainly in the use of the resource, contestation over water resources is also demonstrated through how the resource is defined and described.

Terms such as water stress and water scarcity are commonly used in literature, and so are various colors that define water quality, including white, grey, yellow, and black water. Water that is useful for agriculture is distinctly known as blue or green water, with the latter increasingly gaining prominence in water planning for improved agricultural productivity. Proper management of green water has been shown to improve grain yields in Sub‐Saharan Africa by as much as 2.5 – 6 times.

The arid nature of Sub‐Saharan Africa, coupled with the high evapotranspiration rates, calls for improved management of green water, including reducing evaporation losses, reducing seepage, and increasing the water holding capacity of soils. The value of green water management in Sub‐Saharan Africa is further enhanced by its low‐cost nature when compared to irrigation, which is an area that Sub‐Saharan Africa has also been focusing on as part of the solutions to the increasing food needs of its growing population. Infrastructure for irrigation is costly and not affordable to the majority in Africa. In addition, irrigation can only benefit those communities near the water sources, whereas proper green water management can have benefits to all communities, including those far from a water source.

This issue of the Journal of Contemporary Water Research and Education published in December 2018, features an article written by Clever Mafuta (Programme Leader, Transboundary Waters, GRID-Arendal) titled "The Value of Green Water Management in Sub-Saharan Africa: A Review" (see pp 67-75). 

Status: Completed

Type: Partner Publications

Author: Clever Mafuta

Year of publication: 2019

Publisher: Universities Council of Water Resources and Southern Illinois University

Tags: agriculture Africa water

Read More


GRID-Arendal's activities are nearly always a cooperative undertaking made possible through collaboration with partners and donors.