It is predicted that the dead zone in the Gulf of Mexico could be the largest ever (Photo courtesy of NASA)
A researcher is predicting farm
fertilizers will cause record “Dead Zones”
in the Gulf of Mexico and Chesapeake Bay
this year. Lester Graham reports:
Transcript
A researcher is predicting farm
fertilizers will cause record “Dead Zones”
in the Gulf of Mexico and Chesapeake Bay
this year. Lester Graham reports:
These dead zones are areas where oxygen is depleted. No oxygen and much of the
marine life leaves or dies. It’s caused by nitrogen-based farm fertilizers that are
washed off the fields and into the water.
Donald Scavia is a researcher at the University of Michigan. Using U.S. Geological
Survey data, he predicts the dead zone in Chesapeake Bay will be the sixth largest
on record.
“The six other ones are also not that much bigger than what we’re predicting for this
year.”
Heavy rains and flooding across the Corn Belt washed nitrogen fertilizers into the
Mississippi River system and then on to the Gulf of Mexico. Scavia predicts the
dead zone in the Gulf could be the largest ever.
“What you put down on the land is what gets flushed in those rainstorms. And we’re
putting too much fertilizer on the land. So,
what’s changed over the last three decades is agricultural practices. What changes
from year-to-year is the weather.”
Scavia says better methods of farming could reduce the dead zones.
For The Environment Report, this is Lester Graham.
Construction along the shorelines can put a strain on natural systems. (Photo by Carole Swinehart/Michigan Sea Grant Extension)
One of the more subtle but relentless threats to the Great Lakes is
coastal development. Condos, ever larger and nicer beach homes
and buildings and parking lots in the watershed all have an
impact on the Lakes. As the population grows and the suburban
lifestyle keeps spreading, the health of the lakes is compromised
in countless tiny ways. Reporter Peter Payette finds those tiny
ways all add up:
Transcript
We’re continuing our look at ‘Ten Threats to the Great Lakes.’
Lester Graham is our guide through the series. He says the
experts who were surveyed to determine the threats say rapid
development is among the problems affecting the lakes:
One of the more subtle but relentless threats to the Great Lakes is
coastal development. Condos, ever larger and nicer beach homes
and buildings and parking lots in the watershed all have an
impact on the Lakes. As the population grows and the suburban
lifestyle keeps spreading, the health of the lakes is compromised
in countless tiny ways. Reporter Peter Payette finds those tiny
ways all add up:
Greg Reisig is standing at the edge of a 20-acre construction site
just down the street from the shore Lake Michigan.
Below him is a man-made pond a few hundred feet long. It was a
dry summer around here, but the pond is full.
In fact, Reisig says the water level is always the same.
“And that indicates there’s a lot of ground water flowing
here…there’s a lot of water in this pond and you can see what
was a whole big wetland complex…there’s a lot of cedar and red
osier dogwood…all the wetland plants.”
There are no wetlands here now.
The site in northern Michigan was excavated for homes a few
years ago.
But now the Army Corps of Engineers says the wetlands that
were here need to be restored. A few acres likely will be
restored. But Reisig says almost the whole site was wetlands
once. He expects it will soon be a subdivision with not much
more than a drainage ditch connecting it to Lake Michigan.
“What will that do to the amount of flow of water going into the
bay? Because of hard road surfaces, hard driveways, roofs,
buildings and supposedly fertilized lawns. What will happen to
the water and how will that increase the flow to the bay?”
The developer’s attorney says this is nonsense. Matt Vermetten
says this land was heavily farmed and mined for clay.
“There are pockets of quote unquote wetland and those are there
because of excavation for clay. So is this a wetland complex of
the nature we speak of when we typically speak of such a thing? I
think not.”
Disputes like this are becoming more common around the Great
Lakes. John Nelson is the baykeeper with the Grand Traverse
Bay Watershed Center. The bay off Lake Michigan and attracts a
lot of people. But Nelson says development doesn’t have to be a
problem.
He says the problem is people don’t think about the ecology of
the lakes. For example, east of Traverse City, Michigan, resorts
dominate the coastline. Along the beach, thick stands of sedges
and rushes extend out a few hundred feet. But the sections of
dark green marsh alternate with stretches of clean sand and white
lawn chairs.
(birds calling on beach)
Nelson grew up here and says this part of the lake was never a
sugar sand beach.
“They’ve located in a coastal marsh. Instead of celebrating and
dealing with that they’ve chosen to see it as they would like to
have it and then change it.”
The impacts of the changes are cumulative. Fish and wildlife
habitat is fragmented. The natural filtering properties of the
wetlands are gone.
So every time the city gets a rain shower all the dust and grime
and pollution are washed right into the lake.
Census data show people are leaving many of the Great Lakes
coastal cities and spreading out along the coastline. But it’s not
clear how local governments should plan for the growth.
Mike Klepinger studies land use planning for the Michigan Sea
Grant program. He says it’s hard to make direct connections
between a healthy lake and particular land uses.
“We are getting more planning along the shoreline than we had
thirty years ago in the state. The number of counties and number
of townships that have a plan has gone up, for example. But we
don’t know whether those plans are really doing any good.”
And it’s hard to implement good planning on a broad basis. In
any area, dozens of different local governments might have
independent control over development.
Multiply that by the number cities, townships and counties along
the coasts of the Great Lakes… and it’s hard to see how it all can
be managed so that enough coastline habitat is preserved.
Great Lakes researchers are looking for volunteers to help search for an invasive aquatic plant that can choke out native vegetation, and make it tough to fish or boat. The Great Lakes Radio Consortium’s Erin Toner reports:
Transcript
Great Lakes researchers are looking for volunteers to help search for an invasive aquatic
plant that can choke out native vegetation, and make it tough to fish or boat. The Great
Lakes Radio Consortium’s Erin Toner reports:
Universities and Sea Grant programs throughout the region want people to search bays
and inland lakes for a non-native plant called hydrilla. It’s been found in waterways in
southern states and on the East Coast. Researchers want to make sure hydrilla doesn’t
gain a foothold in the Great Lakes.
Howard Wandell is an inland lakes specialist at Michigan State University. He says
hydrilla forms a net of vines at the surface of the water.
“It’s difficult to motorboat through and obviously trying to cast fishing lures through it is
very difficult if not impossible. And of course then just the idea of even trying to swim
in it, people are very repulsed by the idea of trying to go out and try to recreate in this
tangled mass of vegetation.”
Wandell says hydrilla also blocks sunlight, which can kill native water plants.
A worker samples polluted mud in a test pit. Researchers are trying to break down contaminants in the mud using electrical charges. A German company developed the technology, which U.S. officials hope will be cheaper than dredging polluted sediments.
Photo courtesy of MPR.
One of the biggest challenges facing Great Lakes water quality comes from polluted harbors. Scores of underwater sites have been identified, but cleanup has been painfully slow. Now, some people are taking a new approach – they’re using an electrical charge to clean up pollutants. It’s the first test in this country of the system. Supporters say it’s cheaper and faster than conventional methods. The Great Lakes Radio Consortium’s Bob Kelleher reports:
Transcript
One of the biggest challenges facing Great Lakes water quality comes from
polluted harbors. Scores of underwater sites have been identified, but
cleanup has been painfully slow. Now, some people are taking a new
approach – they’re using an electrical charge to clean up pollutants. It’s
the first test in this country of the system. Supporters say it’s cheaper
and faster than conventional methods. The Great Lakes Radio Consortium’s
Bob Kelleher reports:
Stryker Bay is a lovely little cove alongside the St. Louis River, near Lake
Superior, in Duluth, Minnesota. It’s a gentle water with ducks in the
summer; and a shady hiking path along the shore.
Tim Leland lives along the shore. From his home, he sees waterfowl, and
fouled water.
“Stryker Bay is a shallow bay. It’s six foot at the most of water.
But there’s a silt that’s underneath it, and all this tar and stuff that’s
coming up. Summertime there we do have a lot of oil that makes the surface
there.”
The bottom of Stryker Bay is a biological time bomb. Under the sand, are
pools of oily stuff – that experts call polynuclear aromatic-hydrocarbons,
or PAH’s. For nearly a century, Stryker Bay was an industrial sewer. PAH’s
were first identified under the bay in the 1970’s. That tar like stuff is
still there. There’s not enough money and little agreement how to get rid
of it.
But what if you could make pollution go away by throwing a switch? That’s
essentially what a German based company promises. And U.S. officials are
listening. The first underwater test in the United States of
Electrochemical-GeoOxidation treatment is underway in Duluth. And early
results show promise. It’s a simple concept, according to Ken Whittle with
Electro Petroleum Inc., who describes the process underway behind him in a
pair of water-filled pits.
“It’s a pretty simple kind of thing. If you want to look at it;
if you have a battery charger at home, you plug the battery charger in, you
take the two leads and you connect them to the terminals on a battery. Well,
that’s pretty analogous to what’s going on here.”
Each pit is filled with polluted mud and covered with water. Metal pipes
are sunken into the muck. In one pit, a carefully controlled electrical
charge pushes electrons through the sediment between the pipes. It’s
supposed to break the electron bonds of dangerous molecules; like PAH’s.
What’s left is harmless – like carbon and water.
The test is financed by the Environmental Protection Agency and the U.S. Army
Corps of Engineers: the agency responsible for dredging shipping lanes.
Dealing with polluted sediment is a huge expense, according to Army Corps
researcher Tommy Myers.
“It’s a real big problem for us to dispose of that material. We
can’t put it back into the water. And, typically, we confine it in what we
call a confined disposal facility, and just store the material into
perpetuity and let it break down by natural processes, if it will.”
Officials would rather destroy pollutants than store them, but conventional
methods are expensive, smelly, and noisy. And they all require dredging,
and that’s expensive.
“In this particular technology, it wouldn’t necessarily require
dredging. There’s very little noise or gaseous emissions associated with
it. The main thing is it could be applied in situ; that means in the water,
without having to dredge.”
Proponents say Electrochemical-GeoOxidation is a bargain. Pollution
officials say conventional methods might cost as much as 200 dollars to
clean up a single cubic yard of sediment from Stryker Bay. But, according
to David Bowman with the Army Corps of Engineers in Detroit, electrical
cleanup might cost a quarter of that.
“Our goal with this project was to find a technology that would
work for around one hundred dollars per cubic yard. The vendor talked about
that they might be able to treat material for around forty five to fifty
dollars per cubic yard at Duluth Harbor.”
And the contractor claims the process works fast. A typical site can be
cleaned in just a few months. It’s also supposed to work on metals, like
mercury, which attach to the electrodes, which can then be disposed of in a
hazardous waste facility.
In the Duluth test, PAH’s have decreased by forty five percent in about a
month. That’s promising, although far from conclusive. The process
won’t get every molecule, but it’s intended to reduce contaminants below
dangerous levels.
Tests began in Duluth this summer, but results are several months away.
For the Great Lakes Radio Consortium, I’m Bob Kelleher.
The U-S Fish and Wildlife Service has allowed most of the states in the
Great Lakes region to ease restrictions on hunting Canadian Snow Geese.
And as the Great Lakes Radio Consortium’s Tom Scheck reports, the effort
is being made to protect a region in Canada:
It is predicted that the dead zone in the Gulf of Mexico could be the largest ever (Photo courtesy of NASA)
