edwards aquifer

this is going to be a big big issue, very soon.

"
Of course, underlying the Bexar Co. development
skirmishes is the area's unique aquifer system.
Overlain by karst limestone pocked through like Swiss
cheese and peppered with caves, the water that drains
down from creeks, across dirty parking lots, or out of
wastewater discharge pipes receives very little
natural filtering before it enters the Edwards. From
there, it can move through San Antonio's drinking
reservoir at a rate of thousands of feet per day.
Increasingly, however, San Antonio's sprawling growth
has blanketed the Edwards' recharge zone, threatening
the historic purity of the aquifer water that has
allowed the San Antonio Water System and BexarMet to
pump, chlorinate, and deliver water to area homes and
businesses without the costly central water-treatment
plants found in most other cities. Groups such as the
Greater Edwards Aquifer Alliance have long warned that
tighter controls are needed to prevent the
contamination of the Edwards.

Peace references New York City's decision in 2007 to
spend $300 million on land acquisition to protect its
watershed – a move expected to negate the need for a
treatment plant costing up to $10 billion (and
eventually passed along to customers in rate hikes).
Like San Antonio, New York City is one of only a
handful of cities that has not had to filter its water
because of the pristine job that natural systems
perform. But New York City planners had to remove land
from potential development to do it – not a popular
proposition among the political leadership in San
Antonio. "

full article here