Page 413 - The Engineering Guide to LEED-New Construction Sustainable Construction for Engineers

Low-Impact Development and Stormwater Issues 373

Tool Meaning Applicability to LID
Limit development Only disturb during and after Limited disturbance will reduce
envelope and construction the minimum impervious areas and maintain natural
minimize grading amount of land necessary areas for stormwater management
Remember “out of Do not install LID features that Making LID features a prominent part
sight” may be “out will not be known to users of the site will aid in proper use for
of mind” stormwater management
Choose alternatives Consider alternative Alternative landscapes may reduce
to lawns landscapes to lawns runoff and aid in evapotranspiration
Spread concentrated Use level spreaders or energy Concentrated flows from gutters and
flows dissipators to decrease flow leaders can cause increased erosion
energy and runoff
Modify curb types Use no curbing or modified Concentrated flows from curb gutters
curbing to not concentrate can cause increased erosion and
flow and allow infiltration runoff
on-site
Reduce Limit impervious surfaces and Reduced imperviousness helps limit
imperviousness seek alternative hardscapes runoff and aids in on-site infiltration
that are more pervious
Conserve natural Conserve natural areas This will help maintain on-site
resources that may aid in LID such as infiltration and limit runoff
wetlands and good infiltrating
soil areas
Conserve natural Maintain natural drainage Preexisting drainage courses usually
drainage courses have already stabilized
Reduce pipe use Use open channels where This increases awareness and may
possible also allow for more infiltration and
evaporation
Disperse Provide smaller stormwater This decreases flow rates at individual
storage and infiltration areas and helps in infiltrating and
features throughout the site watering throughout the site
Disconnect Disconnect flow paths such This limits the increase of spot runoff
as from leaders to drives rates by superposition, and disruptive
flows have more time to infiltrate
Maintain time of Maintain predevelopment Altering the t may mean that runoff
c
concentration time of concentration t where will combine with runoff from other
c
possible areas in a different way, which could
increase flows
Educate Consider options for educating Site users should understand the
designers and users from the importance of the LID features
activities on the site and be familiar with maintenance
requirements. Also consider using the
site for education of others, whether
with signage, publications, or visits

TABLE 10.1.9 Other Miscellaneous Tools for LID Designs (Continued)