Most of the projected global population increases will take place in Third
World Countries that already suffer from water, food, and health problems.
Increasingly, agricultural water management must be coordinated with, and i
ntegrated into, the overall water management of the region. Sustainability,
public health, and environmental protection are key factors. More storage
of water behind dam and especially in aquifers via artificial recharge is n
ecessary to save water in times of water surplus for use in times of water
shortage. Municipal wastewater can be an important water resource but its u
se must be carefully planned and regulated to prevent adverse health effect
s and, in the case of irrigation, undue contamination of groundwater. While
almost an liquid fresh water of the planet occurs underground its long-ter
m suitability as a source of water is threatened by nonpoint source polluti
on from agriculture and by aquifer depletion due to groundwater withdrawals
in excess of groundwater recharge. Water short countries can save water by
importing most of their food and electric power from other countries with
more water, so that in essence they also get the water that was necessary t
o produce these commodities and, hence, is virtually embedded in the commod
ities. This 'virtual' water tends to be a lot cheaper for the receiving cou
ntry than developing its own water resources. Local water can then be used
for purposes with higher social or economic returns or saved for the future
. (C) 2000 Elsevier Science B.V, All rights reserved.