There's a temptation to see green building as just about conserving energy; it is the big, sexy problem area after all.  We use too much of it, and most of that use is optional, and wasteful on top of that.  So building infrastructure, where so much of it is wasted, is the likely place to look for savings.  And so we get hung up on insulation and lighting and alternative energy sources.

Not that all that isn't crucial, of course, but with all the energy going into finding alternatives, it's sometimes easy to forget about the other big part of green building standards: water.

Built into the USGBC's LEED standards, for example, are a number of criteria regarding water usage.  Typical solutions are low-flow toilets, rainwater/greywater collection for use in irrigation, and so on.  And these areas of focus--runoff management, wastewater management, and curbing usage--are not just environmental window dressing, but a major component to any comprehensive green building solution.  As much as energy is an issue, water is becoming one as well, as auqefers and reservoirs run low and the potential for drastic climate change threatens many freshwater supplies.

Journalist Daniel Simpson goes into greater detail on the question of water and its importance in the ecological agenda on his blog Untitled.  One of his core points is that the Earth insures that water is a renewable resource, and it should provide enough for us, so long as we use proper management techniques.

And unlike fossil fuel energy and carbon emissions, popular imagination hasn't seized on  a big, easy target like motor vehicles to point at and try to improve to curb our usage.  In fact, our building infrastructure is that fat target, though so far many efforts to curtail water usage have fallen flat.

But LEED standards, and other green building initiatives can certainly change that.