What Are the Main Options for Applying the Multiple-Use Water Services Paradigm? - Rethinking Infrastructure Design for Multi-Use Water Services - page 41

The associated costs for impervious pavements are influenced by the type
of material, the preparation of the site, the installation and the maintenance of
the system. Installation and maintenance is likely to be more expensive than
the construction of conventional impervious surfaces. Typical construction
costs vary from $5 — 10/sq.ft. (Clark et al. 2008a , b ).

What Are Swales?
Swales are shallow, broad and vegetated channels

lter
media to provide on-site treatment of storm water run-off. Storm water is
directed and collected into the shallow depressed area and slowly

filled with porous

lters
through the vegetated soil media where pollution is removed through physical
and biological processes. Water then passes through a transition layer and

finally drains into a drainage layer. Depending on the design, treated storm
water is usually collected through a piping system inside the draining layer
and led downstream to waterways or storage systems, or can in ltrate through

the underlying soils. Swales should also contain an over ow or inlet for ood

events. Swales need regular maintenance.

Schematic of a typical bioretention swale (Source FAWB, Facility for
Advancing Water Bio ltration ( 2008 ))