Page 414 - The Engineering Guide to LEED-New Construction Sustainable Construction for Engineers

374 Cha pte r T e n

Tool Meaning Applicability to LID
Sustainability of LID Consider if the practice will BMPs/LID practices may require
and BMPs remain effective over time maintenance for continued
performance. This must be
incorporated into the site operations.
Also, some practices are removed
because of the lack of knowledge
with respect to their importance by
future users or designers. Making the
features more structurally evident or
using educational tools will improve
their sustainability
Soil Amendments Scarify or add organic or Reestablishes or improves infiltration
or Scarification other amendments to soils into soils
previously compacted or
compacted during construction

TABLE 10.1.9 Other Miscellaneous Tools for LID Designs (Continued)

Chapter
Variable Title Introduced Use
C Rational runoff 2 To estimate the runoff from a site simply
coefficient based on site surface types
CN Curve number 10 To estimate the runoff from a site using
more advanced models
DF Development 2 To determine total building and hardscape
footprint areas. Useful to estimate the impact on the
land with respect to hydrology, vegetation,
and heat island issues
FAR Floor area ratio (also 10 To estimate the intensity of use of the
refer to building site based on built floor area. Useful to
density in App. B) estimate the impact on areal utilities,
transportation, and services
GFA Gross floor area 2, 10 Usually the built floor area used for the
FAR and development density
%imp Percent impervious 2 To estimate the percent of the site
with impervious hardscape. Useful to
estimate the impact on the land with
respect to hydrology, vegetation, and
heat island issues
%impness Percent 2 To estimate overall imperviousness of
imperviousness the site. Useful to estimate the impact on
the land with respect to hydrology. Can
correlate with the rational runoff coefficient
TABLE 10.1.10 Some Common Variables Used for LID Determinations