- Constructed Wetlands Treating Storm Water Runoff
Constructed Wetlands Treating Storm Water Runoff
Storm water runoff is defined as the water sourced from rain or
melting snow flowing over the surface of the land. The quantity of
the runoff is largely dependent on the type of land on which the
rain falls and flows over. In forests and grassy field, due to the
pervious nature of the soil, most of the rain is either absorbed or
evaporated, producing small amount of runoff. On the contrary, the
developed areas with their impervious surfaces generate large
amounts of storm water runoffs. As they flow over the surfaces,
they become rich in pollutants. The storm water runoffs are harmful
to the ecology influencing water quality, aquatic biota and
temperature of natural water bodies like streams and lakes (Ten
Towns Great Swamp Watershed Management Committee, n.d.).
In order to avoid the harmful effects of storm water runoff,
storm water management techniques are employed. There are a number
of storm water best management practices available to treat the
storm water runoff, which are both structural systems which are
engineered and constructed and non structural pollution prevention
techniques. Constructed wetlands are one of the methods of treating
the runoff flow (Sayre, et al., 2006).
Also, the above cited examples have shown that
the constructed wetlands can be used for treating storm water which
is contrary to the previously held assumption. The wetlands have
also introduced some modern trends in the designing of constructed
wetlands. These include multi-train configurations as oppose to the
earlier constructed wetland designs which involve single flow
trains and relatively low aspect ratio cells as oppose to earlier
designs which were constructed with long and narrow cells. (Higgins
& Maclean, 2002).
The above cited example case study show the effectiveness of
constructed wetlands in treating storm water runoffs. The data from
many similar projects testify to the fact that the constructed
wetland improves the storm water runoff quality. The mechanisms at
work in wetlands are quite effective in the removal of pollutants.
In addition to that, the wetlands support wildlife habitat and
landscaping (Surrency, n.d.). Hence, there are dual benefits
attached with this type of green technology.