LAND AS THE RESOURCE - Low Impact Development and Sustainable Stormwater Management - page 73

discontinuous growth, as we all try to escape the urban center. The satellite
communities are, however, insufficient as simple residential places and require
the full complement of other uses. Everybody wishes to live in “the countryside,”
without any loss of convenience, so we bring our employment and market-
place to the new neighborhood, leaving behind the aging city and its compact
conveniences.
Perhaps the best (or worst) example of how a growing region is comprised
of multiple communities that evolved from an urban center is Los Angeles, now
comprised of numerous residential neighborhoods and employment centers. This
sprawling maze of politically separate places, each with a somewhat different
character and quality, is bound together by a complex and intimidating roadway
system that exceeds capacity on a regular basis, as residents try to move from
home to work or retailing. This random and conflicting pattern of land use raises
the question: Have we exceeded the limits of sane development at this place
on the planet? The water supply, wastewater, and stormwater infrastructure that
has evolved follows the same chaotic pattern, with numerous providers, both
public and private, utilizing water resources from distant watersheds, collecting
and treating the wastewaters in dozens of separate systems and largely ignoring
the infrequent consequences of rainfall runoff to coastal waters, except when the
soil adds the element of mud slides and affects residential communities.
3.8 THE LIVING BUILDING AND ZERO NET WATER USE
If LID provides the framework for sustainable water resources management, we
might ask if it is possible to develop an even more sustainable concept that is
based on a zero net water use principle. At first thought, this would seem to be a
contradiction of the land development process; the old adage, “you can't make an
omelet without breaking some eggs” comes to mind. Is it technically possible to
build on a parcel of land without any net increase in water use beyond the natural
hydrologic cycle? While such solutions may be possible for new development in
a watershed without an existing infrastructure, the design of net zero water use
in an urban environment would seem to be close to impossible.
The Cascadia Branch of the U.S. Green Building Council recognized the need
for taking this next step in building technology in the late 1990s and proposed
what they called the Living Building Challenge [4]. The concept was simple:
Design buildings (and sites) that meet all of the required needs of the structure
but create no additional demand for water and energy.
Over the past decade, some 60 building designs, largely in the northwestern
United States, have attempted to meet this challenge. The concept has now begun
to find broader application throughout the country, but few designs have had
success. The zero net energy designs have developed many innovative concepts,
focusing primarily on alternative energy sources (e.g., photovoltaic, geothermal,
wind), and energy-efficient building (HVAC) systems or building materials. A
great deal of valuable information can be found on the Cascadia Web site, or