Natural Treatment of Stormwater Runoff

Abstract

In the Northeastern region of the United States, there is a growing problem in the collection and
treatment of stormwater runoff. In recent years the region has experienced record amounts of
rainfall with the projections pointing to this trend continuing. The Sanitation Department in most
of these areas is responsible for the collection of this stormwater, meaning that the runoff is
combined with, and treated as wastewater. Most of the current water treatment systems cannot
handle these increased demands during large storms and as result hundreds of thousands of
gallons of waste are dumped into the surrounding rivers and streams during and shortly after
these large storms.
The US Environmental Protection Agency (EPA) is levying fines and promulgating additional
regulations for these violations, so a long term solution is necessary. The proposed method of
addressing these needs involves mimicking the natural water cycle which would naturally allow
the water to be absorbed into the ground and then evaporated as opposed to flowing directly into
the sanitation system. This study looked at a local urbanized region, Pittsburgh Pennsylvania, as
a case study considering the locale and its urbanization, the current infra-structure, and the
current and future requirements for storm water runoff mitigation.
The study defined the problem, considered the current legal implications, and then looked at the
types of technologies that could be implemented to address this problem. The technology
ultimately recommended would be a roof spray technology that is capable of collecting the
excess stormwater runoff, storing it, and then spraying it onto a roof where it would be
evaporated. This system would reduce the excess water runoff created during storms that the
sanitation systems cannot adequately handle. The concept for this runoff solution is provided
with an analysis of the actual issues underlying these runoff problems.