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12.7 Selection of Best Management Practices 447
regulatory practices that do not have the level of complexity and possible opera-
tional problems of structural controls.
4. Buildability. This decision factor is directed primarily at the selection of structural
BMPs. Taking into consideration the various aspects of construction, the criteria
investigated under this category include the site requirements, extent of disruption,
and degree of construction difficulty. When relying on complex structural controls,
difficulties inherent in construction and future maintenance might need to be over-
come. Although not a consideration in source control and regulatory control prac-
tice, this factor can be very important for structural controls.
5. Environmental effects. Implementing urban runoff pollution control plans can
affect the environment both positively and negatively. The positive effects on re-
sources result from the removal of pollution sources. Resources that can be pos-
itively affected include water resources, aquatic animal and plant life, wildlife, and
wetlands. The negative environmental effects, which can include aesthetic prob-
lems, cross-media contamination, the loss of usable land, wetlands impacts, and
many others, must also be considered in the assessment.
The importance of this decision factor is becoming more widely recognized.
There seems to be a shift away from viewing urban runoff control structures only
on their pollution control ability. Incorporating structures into new developments
or retrofitting them in existing areas can gain wider acceptance if additional aes-
thetic qualities are considered. For example, unvegetated aboveground infiltration
basins or dry ponds are generally not attractive elements of the environment and
could serve as insect breeding grounds. Natural-looking wet ponds or vegetated
wetlands, however, can be incorporated into the environment and even serve to im-
prove aesthetics. These issues can greatly affect public acceptance.
6. Institutional factors. This decision factor relates to existing governmental struc-
tures, legal authority, and implementation responsibilities. To implement alterna-
tives, the logistical resources must be in place, and the proper authority to pass and
enforce regulatory practices must exist. If the proper authority does not exist, an
analysis of attaining it must be undertaken. In addition to these considerations, the
team should investigate existing urban runoff programs in the community, region, or
state. Often, cost savings can be realized and total program efforts can be reduced
by taking advantage of material and data compiled during these existing programs.
7. Public acceptance. In many instances, the public will be responsible for at least a
portion of the funding required to implement the recommended plan. Public reac-
tion to the urban runoff control plan should, therefore, be assessed through the use
of public meetings. Measuring public acceptance can be difficult, but can be im-
portant to the overall success of a program.
8. Other decision factors. Additional decision factors—such as maintainability, level
of pollution control, or size requirements—can be included in the assessment of al-
ternative plans if they are more important than those discussed above.

Once the final decision factors have been chosen and applied to the alternative plans, the
plans can be assessed by applying a decision analysis tool. Methods for conducting this de-
cision analysis are presented below.

12.7.2.4 Decision Analysis Methods Assessing alternatives takes into account a variety
of factors, both quantitative and qualitative. The type of assessment conducted in these
programs, which involves an integration and comparison of these factors, is an example of
multiattribute decision making and can be performed with various decision analysis methods.