Download “Eco-Treatment System Is Meeting Indiana`s Ground Water Standards”

7830 Rockville Road, Suite C
Indianapolis, IN 46214
Ph: (317) 209-1130
Fax: (317) 209-1131
Fulda, Indiana - A Cost-effective Solution for Small Unsewered Communities
THE PROBLEM: The unincorporated community of Fulda, Indiana is located in the northeast portion of
Spencer County which has the Ohio River as its southern border. Founded in 1845 and centered round the
parish of St. Boniface, Fulda had a problem shared by literally hundreds of small communities in Indiana.
Due to past practices of sewage disposal, soil limitations and small lot sizes, most of the septic systems in
the Town discharged to existing stormwater drains and a small creek. Due to sewage in exposed ditches
and severe odor during warm weather months, the community knew the problem had to be addressed.
Unfortunately, the only options offered by previous feasibility studies were the conventional solutions such
as conventional gravity sewers discharging to mechanical treatment plants or transporting sewage by force
mains to neighboring communities. Options which proved to be too expensive for the residents, both in
terms of capital costs and, more importantly, operation, maintenance and replacement costs.
In an effort to find a viable solution to its problem the community formed a Regional Sewer District (RSD)
and sought help from Bernardin, Lochmueller and Associates, Inc. and Natural Concepts Water Quality
Engineering, LLC, a subsidiary of Bernardin, Lochmueller and Associates, Inc.
The goal of the RSD was to implement a community sewage collection and treatment system that would
have a monthly user fee of approximately $60 per month. Previous investigations by concerned community
members and county representatives had resulted in conventional systems that would cost anywhere from
$80 to $120 per month depending on finance sources.
Based on preliminary planning, the sewered area consisted of 64 total connections; 59 residential
connections, 1 church, 1 tavern, 1 gas station, 1 community center and 1 small industry. The average daily
design flow was estimated to be 8,750 gallons per day.
THE SOLUTION: Natural Concepts Engineering, Inc., prior to becoming Natural Concepts Water Quality
Engineering, LLC, had developed a natural treatment system that shows promise for meeting Indiana
ground water standards for drinking water on a consistent year-round basis. The system, which has been
named the Eco-Treatment SystemTM, consists of three primary components; a 9,700 square feet
subsurface-flow constructed wetland, a vegetated recirculating gravel filter which lies atop the first 1/3
portion of the influent end of the subsurface-flow constructed wetland and a 3.6 acre soil absorption system
using GEOFLOW, Inc.’s subsurface drip irrigation systems.
The Eco-Treatment SystemTM is proving to be cost effective,
particularly in operation and maintenance costs, which are 1/4 to
1/3 of the costs for conventional treatment systems.
The key features of the Eco-Treatment SystemTM are:






Evapotranspiration – significant reduction of effluent
discharged to the subsurface drip irrigation system during
warm weather months.
Root systems that help to prevent plugging of media and
detain the recycled water, which dramatically increases
the detention/treatment time within the aerobic portion of the vertical wetland.
An anoxic zone with a continuous input of carbon to drive denitrifcation.
Requires only pumping for recirculation of the wastewater within the wetland.
Maximizes total nitrogen removal.
Green space utilization using GEOFLOW, Inc.’s subsurface drip irrigation systems.
PERFORMANCE:
The system for Fulda was permitted as a land
application project which requires the application area to
besized so that the pounds of Nitrogen applied on an
annual basis does not exceed the theoretical uptake of
the planted crop. However, the specific goal in the
development of the Eco-Treatment SystemTM was to
have a system that was mechanically simple and that
could meet Indiana’s groundwater standard for total
nitrogen concentration of 10 mg/l or less on a year
round basis. The testing results from the first 12
months of operation for the Fulda system, while well
within limits established by its land application permit,
show the promise of obtaining the this goal, with effluent
averaging less than 10 mg/l on an annual basis.