Watching Artificial Wetlands

  • Natural wetlands that are developed are supposed to be replaced by man-made wetlands somewhere else. (Photo by Lester Graham)

More than half of U.S. wetlands have been drained for
development, farmland, and other purposes. That’s 100
million acres now dried up. The Bush administration has
continued “no net loss” policy of any more wetlands.
So, when someone wants to drain a marsh or a swamp for,
say, a new housing development, they’ve got to build a man-
made wetland to replace it. But a new study is finding that
most of those man-made wetlands aren’t doing very well.
Julie Grant reports:

Transcript

More than half of U.S. wetlands have been drained for
development, farmland, and other purposes. That’s 100
million acres now dried up. The Bush Administration has
continued a “no net loss” policy of any more wetlands.
So, when someone wants to drain a marsh or a swamp for,
say, a new housing development, they’ve got to build a man-
made wetland to replace it. But a new study is finding that
most of those man-made wetlands aren’t doing very well.
Julie Grant reports:


(Sound of truck stop)


These 18-wheelers are lined up on a huge black parking lot
behind a truck stop off Interstate 80. Looking at it, this
wouldn’t seem like the ideal place to create a wildlife area.


But wetland ecologist Mick Micacchion has chosen this place
to show that man-made wetlands can be successful.
At the edge of the parking lot, we walk down into some
brush. The ground is mostly even, there’s no big ditches… just
some gentle slopes. The weather’s been dry the past few
weeks. But water starts seeping into my shoes:


(Mike:) “You getting wet?”


It might be bad for our shoes, but saturated soil is a good
sign for a wetland, and so are a lot of the plants we’re seeing.


As we walk, Micacchion stops at plant after plant…
Impatients, monkey flower, and lots of grass-like plants called
sedges. These all grow in wet soil:


“So even in sedge community, we’re seeing some diversity.
Which is unusal in a wetland that’s only been constructed for
a few years. But it tells you some good things are going on
here.”



Checking out what’s going on at wetlands like this one is a
new job for Micacchion. He works for the state government.
Federal officials used to take authority over wetlands as part
of the Clean Water Act. But a U.S. Supreme Court decision
six years ago took away some of that federal authority, and
left responsibility for these kinds of isolated wetlands up to
states.


That’s why Micacchion is studying man-made wetlands for
the Ohio EPA: to assess how well the state program is
working.



Wetlands that work are not only good for wildlife…they
provide a holding area for water when there’s heavy rain.
That helps prevent flooding. It also gives polluted sediments
time to drop out of the water, so it’s filtered, which means
it’s cleaner by the time it drains into streams, rivers and
lakes.


But this story of a successful man-made wetland is the
exception. A study Micacchion’s is conducting is finding that most are in fair
or poor condition.


The loss of functioning wetlands can lead to more flooding
and polluted waterways.


Micacchion says when developers drain natural wetlands,
they often don’t understand how to build artificial wetlands to
replace those original systems.


Our next stop is a good example of that. We pull into a parking lot just behind a busy street
of car dealerships. One company drained a wetland back
here to build an access road. And to replace it, they built a
pond.


Tom Wysocki walks out of the car dealership to see what
we’re up to out on his property:


“Is there someone in your office, who I mean, is this your
Beliwick in the office?”


“It would come to my desk.”


“You’re the wetlands expert at Klaben Ford.”


“I’m the expert on everything.”


Originally, this site might’ve correctly designed for a wetland. But
Wysocki decided it didn’t look right to him because it wasn’t
holding water. So he had it dug again to make a pond.


He and the actual wetlands expert definitely have a different
idea about what a successful wetland looks like. Micacchion
says a pond isn’t a wetland:


“Usually with natural wetland systems, the slopes
are very gentle. And you have to walk out maybe 15-20 feet
before you get a foot deep of water. Here, you could step in
and maybe immediately be in a foot to two feet of water. And then, the deep
water it becomes difficult for certain plants to grow.”



The area is dominated by a couple of kinds of plants. But
Micacchion says they’re both invasives. And they’re
crowding out the native wetland plants. Native plants would
provide habitat for wildlife:


“This is all reed canary grass. The biggest problem with it, it
comes in, and you can see it gets very thick. It’s pretty much
only species you see growing with just a few other things you see
poking their heads up here and there. This eliminates some
of diversity we might see otherwise.”


Micacchion says his study is finding that this is pretty typical.
Even if a developer starts out with right kind of plan,
somebody can make an arbitrary decision that defeats the
original purpose. But Micacchion says it doesn’t have to be
that way. Man-made wetlands can work if they’re designed
by ecologists and engineers who understand the details of
what makes natural wetlands so useful.


His office is creating wetlands guidelines. They want
developers to understand the natural wetlands they’re destroying and what they need to do to replace them.


For the Environment Report, I’m Julie Grant.

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