Approach

Aqua per Capita Approach to the Topic of Population and Water Issues
Math and Meaning – The Equity in Equations

  

[# of people] x [water use per person] = [total water use]

Population/resource equations can seem like abstract issues of math, removed from our experience – some technical problem to be solved by engineers or policy makers. But “equations” which come from the same root as “equity,” are ethical matters. They are not merely technical expressions, but have serious human and environmental implications. The form of our math belies our values and assumptions about  what we are “solving for.”

[# of people] x [water use per person] = [total water use]

In this version, we take population and water lifestyle as givens, and solve for needed water to be provided. More water treatment with associated energy inputs, more infrastructure, bigger pipes and depleted aquifers until...

[fresh water supply] divided by [# of people] = [water use per person]

Here, we take available fresh water and population as givens and solve for the needed conserving water lifestyle. Efficient plumbing fixtures?, less irrigation?, water rationing? unmet drinking needs?

[fresh water supply] divided by [equitable & reasonable water use/person] = [# of people]

In this version, we take fresh water capacity and basic human rights to a reasonable needed amount of water and solve for population numbers that can be supported.

Of course we can and should solve for all three parts of this equation at once and consider other variables not shown here, such as the economics involved, the environmental implications of extracting water from aquifers, the impacts of water treatment, and the prevention of pollutants to our water bodies to protect and enhance the available supply.

While objectivity is needed for accurate measurements and projections to meet needs, the form of our population/water equations, the variables included, and what we are solving for are ethical choices not engineering choices that require each of us to participate in defining the mission behind the math of “aqua per capita.”