Greening Sustainability Brochure - North Carolina A&T State ...

Constructed Wetlands
G.B. Reddy, PhD
Professor, Natural Resources and Environmental Design
Animal production which is
vital for protein demand and
the economy is one of the
regulations. Constructed wetlands have
been used or at least investigated for
treatment of animal waste in the United
major components of United States
States and around the world. Constructed
agriculture. Animal production brings along wetlands are cost- effective, passive, easy to
a baggage of waste production and
operate, efficient in nutrient removal,
environmental problems. These problems flexible in soil specificity, and
are related to odor, pathogens,
environmentally friendly. Even though
concentration of nutrients, and limited land constructed wetlands have been proven in
availability for treatment. Particularly in the nutrient removal, it could be a challenge to
swine industry, large swine production
treat highly concentrated swine wastewater
occurs in confinement and generates large and to understand the function through its
quantities of waste in a limited per-unit
physical, chemical, and biological processes.
area. Traditionally, swine operations in
North Carolina A&T State University
many parts of the world flush the waste
received approximately $20,000 from the
from swine houses into an anaerobic lagoon Army Core of Engineers to construct
and from there the lagoon water is applied wetlands at the swine unit on the
on the land for treatment. In many places, University Farm. Six marsh-pond-marsh
the limited land and continuous
constructed wetland cells (44 m length and
applications of wastewater pose a threat to 11m width) were designed in 1995. Each cell
the surface and ground water quality.
had a 20 m middle pond section and 10 m
marsh section at the influent and effluent
The constructed wetlands can be a pre-
ends. Shallow sections with marshes at the
treatment technology before land
influent and effluent ends and deep section
application to reduce water quality
in the pond had an operating water depth of
pollution and to meet environmental
15 cm and 75 cm, respectively. The marsh
11