Water Footprint

Yesterday's column by Philadelphia Inquirer architecture critic Inga Saffron references a forthcoming change in the way the Philadelphia Water Department will be billing its customers. By next year, a much higher proportion of our monthly bill will come in the form of our contribution to storm-water run-off, as calculated by the amount of impervious surface on our lots. So low-water users with massive paved footprints will now have to pony up more, for example.

I had gotten the advance skinny on this from a colleague of mine who works in the Water Department, and it makes complete sense to me. After all, you want to give people incentives to do things that lower municipal costs and environmental impacts. And if your property causes more storm-water run-off and thus more problems for someone else to deal with, you should have to pay more. And, conversely, if you have designed your property in such a way as to minimize this negative spillover, you should be rewarded with a lower bill.

The big headache will be how to transition to such a regime - new plans can account for the new calculus in determining whether and how to include more pervious surfaces, but while you want to motivate existing landowners to adjust if needed, those adjustments can't happen instantaneously. So politically and logistically, that'll be a challenge. But the technical side of things appears to be in place to do billing in a more economically and environmentally rational manner. Kudos to the Water Department in that regard.