The most recent issue of the magazine Population Connection notes several interesting things.  First, the world’s population grows by 80 million people per year, predominantly in areas that are not “first World” countries.  In many of these places water is limited – 1.2 billion people live in these areas. By 2030, 40% of the people, especially those in these areas will be facing water deficits that will increase their risks.  Some of these deficits will be exacerbated by climate changes.  Agriculture is responsible for 70% of water use, and that number is not expected to decline as the need for agricultural products increases with time.  So clearly water use and population are related, just as carbon dioxide concentrations in the atmosphere and population appear to be related. Worse yet, the number of urban residents that do not have access to wastewater services is expected to increase by 50%.  The good news, not so much in the US, where such services are expected and available to the vast majority of people.  So the problem – most of these people live in Third World countries that lack both the economic resources and social infrastructure to deal with these problems.  This is what Engineers Without Borders is trying to address but it does raise that question – what are the social consequences of trying to help them?  Surely engineering ethics say we should help protect the public health, safety and welfare, which this work does.  But on the other side, if they develop more and add more people, does that add to the strain on limited resources in these areas which might damage the public health safety and welfare.  Which is the more critical issue?  And how do we decide? How should engineers evaluate the conflict between public health and sustainability from an ethics perspective? Just asking?