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408 Chapter 12 Urban Runoff and Combined Sewer Overflow Management
sources enhances water resource improvement. Further, it assumes that demonstrating
water resource benefits increases public support of urban runoff management and control
programs as citizens become more closely attuned to overall water quality goals. Also mu-
nicipalities should investigate water resources within their region to develop priorities so
that limited resources can be targeted to areas with the greatest potential for improvement.
Various levels of detail can be used in this assessment, ranging from simple unit load meth-
ods to complex computer models.

12.3.8 Screen Best Management Practices

Once the water resource problems have been prioritized, specific water resource problems
and their sources can be addressed. The program team should compile a list of various
runoff management and pollution prevention and treatment practices and review them for
their effectiveness in solving the prioritized problems. The next two sections include brief
descriptions of various nonstructural and structural best management practices (BMPs).
Also described is the initial BMP screening step, when potential practices are reviewed for
their applicability to the watershed and water resource problems of concern. While the
team initially faces a large number of potential practices, obviously inappropriate practices
are eliminated in this step based on criteria such as the primary pollutants removed,
drainage area served, soil conditions, land requirements, and institutional structure.
Following this initial screening, the program team will have a list of potential practices to
be evaluated further.

12.3.9 Select Best Management Practices
During this step, the program team investigates the list of potential pollution prevention
and treatment practices developed from the previous step to determine which to include in
the plan. More specific criteria should be used for analyzing these potential practices than
during the initial screening. To make the final selection, the program team must use the an-
alytical tools developed during the ranking and assessment of problems, as well as deci-
sion factors such as cost, program goals, environmental effects, and public acceptance. As
with the initial screening step, these evaluation criteria depend on established priorities.
Generally, the selection process yields a recommended system of various pollution preven-
tion and treatment practices, which together address the pollution sources of concern.
Availability of required resources to implement the practices is a major consideration. If
needs and resources don’t match, the municipality might have to adjust its expectations to
what realistically can be accomplished. Both structural and nonstructural practices might
be required.

12.3.10 Implement Plan
After choosing the best management and treatment practices, the program team moves
from planning to implementation, which often occurs through a phased approach.
Inexpensive and well-developed practices can be implemented early in the program as
pilot or demonstration studies; and these results might influence further implementation.
Given the added requirements of implementation, operation, and maintenance, the original
program team might expand to include members with more construction experience. Also,
funding sources are needed for initial capital expenses and continuing operation and main-
tenance costs. Nonstructural practices must be implemented, and the team must arrange for
the detailed design and construction of structural practices.