Sometimes parking is hard to find. But too often you drive across acres of empty spaces before you settle on a spot. Rain on those empty acres collects pollutants and rushes them into the storm sewers, and on to the Chesapeake Bay.

Purdue University scientists have done some calculating, and they've found that empty spaces in the region they surveyed outnumber actual drivers by three-to-one. Tons of oil and heavy metals are swept off the blacktop when it rains and sluiced into the nearest waterways.  Loads of salt are spread each winter to keep the space free of snow and ice, not to mention the fuel burned to shove the snow aside. The result is a degraded environment and more urban flash flooding. 

I know there are rules about how much parking is needed for each square foot of retail space. But do some builders go overboard? Could we revisit those rules and see if they could be modified under certain circumstances to reduce the amount of impervious, paved surfaces we build? Could we provide a tax credit, or some sort of incentive for retailers to dig up unneeded blacktop and plant something that would absorb more runoff?

Am I dreaming? Does the WalMart out in Hunt Valley really need parking all the way out to the Light Rail station? Do you have an expanse of parking you drive by every day that is never filled? Leave a comment and nominate your favorite overkill-parking lot. Send me a digital photo and I'll post it.