system or Ontario’s upper-tier municipalities like Metro
Toronto.
There is broad consensus that urban water quality
impacts can be reduced with careful site planning
Protecting farmland
to  reduce  impervious  cover  and  increase  water
If there is a concern with the conversion of productive
farmland to urban or suburban development, a variety of
detention.
policies and tools can be helpful in protecting farmland.
These include agricultural zoning regulations, tax incen-
of development because they generate employment
tives, right to farm legal protections and agricultural
together with immediate and measurable tax revenues.  In
districting.  Purchase of development rights, otherwise
part, these pressures derive from the increasing globaliza-
known as purchase of agricultural conservation easements,
tion of industry and the move to “mega scale” development
and transfer of development rights are gaining increased
in many industrial sectors.
attention as they preserve private ownership, and provide
permanent protections for rural and agricultural lands.
John Sewell argued that municipalities should be investigat-
Purchase of development rights allows development rights
ing what Jane Jacobs termed “import replacement” (Jacobs
to be sold to an entity, such as a state or local government
1961).  That is, municipalities should be exploring oppor-
or land trust, which holds on to that right to keep the land
tunities to locally produce the goods and services that are
from being developed (in the form of a conservation
currently imported from external sources with associated
easement).  The land is retained in private ownership and
road networks and vehicular emissions.  Import replace-
continues to be used as rural or farmland.  A transfer of
ment may be a means of creating a range of employment
development rights allows landownders to transfer the
opportunities, with associated economic development,
right to develop one parcel of land to another parcel of
closer to home, and thus reducing both industrial/commer-
land.  When the development rights are transferred,  the
cial and commuting traffic.
parcel that “sent” the development rights becomes re-
stricted with a permanent conservation easement, much
Several speakers noted that development codes may best
like purchase of development rights, and the parcel that
be redesigned through consensus-based programs such as
“received” the development rights is allowed to develop at
Maryland’s “Builders for the Bay.”  Consensus-based
a higher density than ordinarily permitted in that area.
planning has great value in building support among those
The transfer of development rights is more complex to
most affected by development changes, especially builders
establish and administer and therefore is not as widely
and developers, and has added advantages in creating a
practiced as the purchase of development rights, but is
mechanism for broader public education.
gaining interest due to its ability to promote trading of
rights among private parties in the interest of growth
Options for the Prevention and Management of Urban
management.
Water Quality Impacts
Reducing impervious cover and increasing
Lawrence Libby and William Page reviewed a number of
water detention
options to prevent and manage water quality impacts from
There is broad consensus that urban water quality impacts
urban and urbanizing areas, as follows.
can be reduced with careful site planning to reduce
impervious cover and increase water detention.  The
Managing the geographic extent and
development principles (see Appendix I) of the Center for
ecological footprint of urban growth
Watershed Protection (2003) emphasize these outcomes.
Municipalities can set distinct boundaries on urban growth,
They include changing planning and construction stan-
essentially by drawing a line on a map within which urban
dards to allow:
development may occur, known as urban growth bound-
aries.  Urban growth boundaries are usually reviewed and
narrower street widths and smaller parking areas;
revised every 20 years or so.  Their efficacy may depend on
reduced side and front setback requirements for
how, when, and by whom these boundaries are enforced.
residential dwellings (i.e. build houses closer together
A related concept is Urban Service Boundaries, which limit
and closer to the street);
where central water and sewer services are provided.
roof downspout disconnection, with redirection of
When coupled with a planning requirement that all new
rooftop drainage to lawns and gardens;
development must be served by centralized services, Urban
use of porous surfaces such as walkways and parking
Service Boundaries can de facto limit the extent of growth.
lots;
Urban development boundaries may benefit from regional
use of grassed swales and other natural systems rather
planning oversight, such as the Portland (Oregon) Metro
than paved surfaces or culverts;
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