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OVERVIEW:
A Brief Description of the
Mahoning
River
and the Restoration Project
The Mahoning River begins near Winona in Columbiana County, a few miles
southeast of Alliance, and flows through five counties of eastern
Ohio (Columbiana, Stark, Portage, Mahoning, Trumbull) and one county
in western Pennsylvania (Lawrence)*.
(See watershed
map.)
The
Mahoning
River
joins the
Shenango
River
in western
Pennsylvania
to form the
Beaver River
which flows into the
Ohio River
(see the
US
map). The “upper
elevation of the river”—
Alliance
to Leavittsburg—is the
portion that is more rural and did not experience heavy industrial
use and is, therefore, not heavily contaminated.
The mainstem (“lower elevation”) of the Mahoning
River—northwest of Warren to its confluence with Shenango River at
Mahoningtown, Pennsylvania (near New Castle)—was heavily
contaminated by household waste until 1965 and the numerous steel
mills and manufacturing plants that used the river as an
“industrial sewer” for almost 100 years.
Toxins from that use have settled in the sediment in
the riverbed and banks. Research
must be done to investigate removing and treating the sediment in
order to restore the river. The US government has issued orders to
the US Army Corp of Engineers for “ecological restoration of the
river” from Warren to Lowellville, Ohio (the mainstem of the river
in Pennsylvania did not experience as much pollution as the mainstem
river in Ohio). The
cleanup of the industrialized
Mahoning
River
is referred to as “The
Mahoning River Ecological Restoration Project” and is described
more fully below.
*
The
tributaries of the
Mahoning
River
travel through eight
counties (Columbiana, Stark,
Portage, Geauga,
Ashtabula, Trumbull, Mahoning, and
Lawrence), but the
Mahoning
River
travels through only six
counties.
CONTENTS
Background:
The
Mahoning
River
was polluted during the
nineteenth and twentieth centuries by two major sources:
the steel industries and the human population (the lack of
waste water treatment plants alongside the
Mahoning
River
until the 1960s also
contributed to the river's pollution; until 1965, raw sewage from
homes and businesses went directly into the river).
The industrialized
Mahoning
River
is the section of the
waterway that was used by steel mills and factories.
It includes approximately 30 miles of the river—starting
just west of
Warren
in Leavittsburg and
continuing southeast to
Lowellville
,
Ohio
at the border of
Pennsylvania
. There are 10 low-head
dams in this area of the river.
These dams were built by the steel industries to increase the
amount of water in front of each mill complex in order use it to
cool the hot steel and machinery (that water, which after being used
was often 100 degrees and filled with chemicals, was poured directly
back into the river). Over
decades of this practice, most of the toxins from the steel mills
were washed downstream to the Beaver and
Ohio
Rivers
, while some of the toxic
sediments settled on the bottom of the
Mahoning
River
and accumulated in large
amounts behind these
low-head
dams.
Estimates provided by the Ohio EPA and US Army Corps of
Engineers explain the scope of the cleanup/restoration project.
There are approximately 462,000 cubic yards of contaminated
riverbed sediments. Along
the shore in the banks, there is an additional 286,000 cubic yards
of contaminated sediments. This gives a total of 750,000 cubic yards
of material spread out over a span of 30 miles to be cleaned up.
The
Mahoning
River
presents some complex
problems to scientists and engineers.
Only 45% of the contaminated sediment is in one location:
behind the Girard Dam. The
other 55 % of contaminated sediment is spread out over those 30+
miles. The dispersed
nature of the deposits of sediment calls for numerous studies and
the development of varying approaches for removal of the sediment
and its disposal after removal.
The contaminated sediment on the river bottom could be dredged
or capped. The
sediment that is removed will either go to a landfill or will be bioremediated.
The riverbanks are another story. Most
often, where the river bends, deposits of mud and silt have built up
and that newer, less toxic sediment has covered over the
contamination allowing for growth of trees.
To simply remove the trees and dirt would expose the upper
banks and cause erosion. On
the other hand, to leave the contamination under the banks runs the
risk of potential exposure and seepage.
Such an exposure could easily happen when trees fall and
their roots expose the contamination below.
That would allow contaminants into the river.
Treating this contamination may require the technological
solution of bioremediation.
Just how “toxic” or “hazardous” is the Mahoning?
(See River Contamination for a full description.)
Descriptions
of Four Phases of the Mahoning River Ecological Restoration
Phase
1: Reconnaissance (1997
– 1999)
This phase was completed in 1999 by the US Army Corps of Engineers.
The objective was to address the problems and opportunities
for ecosystem restoration related to contaminated sediments in the
lower, industrialized
Mahoning
River
(Leavittsburg to
Lowellville). Work for
this study includes an evaluation of existing technical and
historical data, the collection of new data, and the analysis of all
the data.
The objective of this study was to investigate the current condition of
the river and riverbanks, identify where most of the pollution has
settled, and to verify the need to restore the
Mahoning
River.
The study demonstrated that the
Mahoning
River
restoration was needed and
that the feasibility study should commence.
Phase
2: Feasibility (2002 –
2004)
A feasibility study is now in progress and investigates how the
restoration should be done, how much it will cost, and who will pay
for it. Many impacts
will be analyzed during this study:
environmental, socioeconomic, and engineering.
The current estimation for
Mahoning
River
restoration is about
$100,000,000; $65,000,000 will be paid for by the
U.S.
government, while the funds
from the other $35,000,000 can come from the State of
Ohio
and local communities along
the
Mahoning
River.
During this phase, important decisions will be made as to exactly how
the
Mahoning
River
will be restored.
Disposal of the sediment remains an important unanswered
question. It will be
wet, probably will require “dewatering” and may contain
unacceptably high levels of toxins.
One solution might be to establish disposal sites along the
river to detoxify the toxic sediment by using bioremediation.
Before returning the sediment water to the river, it too will
need to be treated at wastewater treatment plants.
To construct new wetlands and apply bioremediation for the
restoration would provide permanent filters for water entering the
river—including storm-water or outflows from sewers.
Wetlands would replace the original ones that were lost over
the last century through excavation along the river corridor or channelization
of the river by industries. They
could become public recreational lands.
The work of Phase 2, the Feasibility Phase, is projected to be done in
2004 and includes these tasks.
- Gather more
samples and information to check for toxins in the river channel and
near-shore areas.
- Study and
decide on the correct methods or combinations of methods to be used
for restoration (i.e.: look
at all the specific details and decisions about dredging,
encapsulating,
bioremediation,
excavation and stabilization,
treatment of water resulting from any dredged material and disposal
or beneficial use of material that is dredged, excavated, or
bioremediated, etc.)
- Estimate how
gas, water, sewer or electric lines will be affected by the
restoration project and decide where relocation is required.
- Survey the
banks and make plans that minimize the toll on wildlife and the
riverside forest as well as the erosion of soil on the bank, when
construction is performed that will remove the earth on and under
the banks that are saturated with oil and grease.
- Decide how the
substrate, the bottom of the river, will be restored.
Phase
3: Pre-construction
(2005 – 2006)
This phase includes the pre-clean-up activities of
engineering and design. A
Design Project Cooperative Agreement (PCA) will be signed, which
initiates a two-phase project: the
preparation of detailed design reports as well as plans and
specifications. The
cleanup, itself, will take ten years and will deal with
approximately 750,000 cubic yards of material that is spread out
over 34 miles. Given the
scope of the overall cleanup project, very special planning is
required. This will
commence in 2005 and end in 2006.
Carmen
Rozzi, Army Corp of Engineers and project manager for the
Mahoning
River
restoration offers this
technical description of Phase 3:
“By
removing the contaminated sediments we are creating a new sectional
template throughout the study reach. We don't do this
haphazardly; various items need to be investigated and
designed. Hydrological and Hydraulic design is required to
establish existing conditions and for determining the new
conditions in accordance with the various plans for removing
the sediments we will be investigating [in Phase 2.]
Additionally, geotechnical characterization needs to be accomplished
along the reach. Removal and remediation techniques need to be
explored. Settling ponds for temporarily storing and bleeding off
the excess water prior to removal to an off-site location need to be
designed; treatment of bleed-water needs to be designed. Cost
engineering estimates need to be developed for each alternative
investigated… a variety of items too numerous to mention need to
be accomplished.”
Phase
4: Construction (2007
– 2017)
Finally, the restoration begins. Sometime
in 2007, the methods selected in Phase 2 and plans developed in
Phase 3 will be enacted. The
restoration itself will occur in stages, beginning in Trumbull
County with the Warren “pools” (small reservoirs on the
river formed by low-head dams), then Upper Girard, Lower Girard, and
moving into Mahoning County to the Youngstown/Campbell pools and
completing in Struthers/Lowellville pools.
During this process, the river bottom would be severely
disturbed, adversely affecting the plants and animals that are
living in the river. However,
throughout this section of the river, the plants and animals are
already severely adversely affected by toxic sediments and
impoverished habitat diversity.
In order to restore ecological function to the river, habitat
diversity must be restored. That
will happen as the sediments now covering the river bottom are
replaced by a diversity of substrates.
Project
Completed: estimated
2017
In the end, the
Mahoning
River
will flow with much cleaner
water and the contact ban will be removed and people will be able to
fish, boat, and recreate in and along the river.
The river is expected to support a healthy fish population
again (See “Fish Report” & “Future Recreation Once the
River is Restored”). Five
of the low-head dams will be either removed or modified; perhaps fish
ladders will be installed. Some
of the riverbanks and riparian zone will be restored; new wetlands
will be created. Between
now and completion, the many phases of the project may change as
technology advances. The
river restoration should be completed in 2017.
Resources:
Environmental
Protection Agency
River
corridor and wetland restoration principles
http://www.epa.gov/owow/wetlands/restore/
Principles for the Ecological Restoration of Aquatic Resources
http://www.lakemerced.org/homepage.html
US Army Corps of Engineers
http://www.lrp.usace.army.mil/pm/mahonoh.htm
(high level project description from Army Corp of Engineers)
The
Ecological Restoration of the
Hudson River
A look at the
Hudson River
and its restoration from PCBs released by General Electric.
(PCBs are also a pollutant in the
Mahoning
River
.) http://www.nywea.org/
From the US Fish & Wildlife Service,
Division of Environmental Quality:
This case addresses natural resource injuries that have
occurred due to the release of hazardous substances, particularly
polychlorinated biphenyls (PCBs), to the Hudson River, primarily
from General Electric’s Hudson Falls and Fort Edward, New York
manufacturing plants. http://contaminants.fws.gov/restorationplans/HudsonRiver.cfm
The NYS Department of Environmental
Conservation (DEC), National Oceanic and Atmospheric Administration
(NOAA), and US Fish and Wildlife Service (FWS) are developing
restoration options for Hudson River natural resources injured by
PCBs and other hazardous substance contamination.
http://www.darp.noaa.gov/neregion/hudsonr.htm
How One Person is
Making a Big
Difference
An inspiring story about
one young man and his growing efforts to clean the Mississippi and
Ohio Rivers. http://www.cleanrivers.com/
http://www.americanrivers.org/groupoftheweek/chadpregracke.htm Academy
of Natural Sciences' Institute for River Restoration
The Institute for River Restoration is an interdisciplinary group
within the Patrick Center for Environmental Research that seeks to
advance the science of restoration ecology and the application of
effective watershed restoration practices.
http://www.acnatsci.org/research/pcer/institute.html
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