Posted by: Christopher L. Overcash, PE, BCEE, LEED AP, ENV SP
Part 2 of this water security blog will focus on key trends that will impact water use and availability. Most importantly, by 2030 the water used for supply is expected to increase by 30%. At the same time, food and energy production are both expected to increase by 50% each. This change is expected to create a 40% shortfall of available freshwater resources versus demand by 2030.
Another significant trend is that by 2025 meat production is expected to increase by 50%, which is faster than overall food production because of the global trend toward a larger middle-class. As populations move into higher incomes, they transition to diets that include more meat. This trend becomes problematic in the context of the water-food nexus because of the amount of water used for meat production. For example, it takes about 10 times the amount of water to produce the same caloric value of food with beef than it does to produce it with grains. In the case of poultry, it takes approximately three times the amount of water than to produce the same amount with grains. Because of the significant impact to water resources, meat production will not be sustainable in a resource constrained future. Today, much research is being expended to develop meat alternatives.
Another important trend is that water use is rising two times faster than that of population growth. This is caused, again, by the increase in the amount of middle-class population worldwide. The increase in affluence generally leads to a population being able to utilize more water resources per capita.
Finally, another vital trend to be aware of is the overuse of groundwater in many areas of the world. Groundwater makes up significant percentages of water use in many countries. For example, Mexico’s water use is derived 20% from groundwater, China 25% and India 56%. Use of groundwater at these rates is not sustainable because recharge of groundwater is very slow compared with the rate of withdraw. In the case of India, this is especially problematic because the underground aquifers supplying 56% of the water in India are expected to become expended later in the century. Thus a very large population base will need to find an alternative water source.