Tag: silt

Construction Sites Mucking Up Rivers

  • The EPA says sediment runoff rates from construction sites are typically 10 to 20 times greater than from farmland. (Photo courtesy of the National Centers for Environmental Prediction)

Some home builders say the housing market
is tough enough. They don’t need environmental
regulations that make it tougher on them. But
some “green” builders say the housing industry
can improve the environment, do the right thing
for communities, and still make money. Julie Grant
reports:

Transcript

Some home builders say the housing market
is tough enough. They don’t need environmental
regulations that make it tougher on them. But
some “green” builders say the housing industry
can improve the environment, do the right thing
for communities, and still make money. Julie Grant
reports:

Have you ever driven by a construction site and seen all that dirt? A lot of that dirt is washed off the site by
rainstorms and ends up in local creeks and rivers.

Russ Gibson is with Ohio Environmental Protection Agency.
He says that dirt kills aquatic bugs and fish.

The dirt covers up gravel bottom streams – that fills holes
where bugs want to live. If bugs can’t live it mucks up the
food chain. Gibson says fishermen know when this
happens.

“You’ll have some of the smaller fish and the bait fish, like
minnows and darters, will feed on the small bugs that live
there. If you don’t have bugs to feed the bait fish you don’t
have bait fish to feed the big fish.”

Beyond that, the silt from construction sites can also muddy
up where fish lay their eggs.

And enough construction dirt can fill a stream so much that it
can make flooding more of a problem.

So, how much dirt are we talking about?

The EPA estimates that 20 to 150 tons of soil per acre is lost
to storm water runoff from construction sites.

That means every time a new house is built, truckloads of
soil can wind up in local streams.

If a homebuilder pulled a truck up to a bridge and dumped a
load of dirt into a creek, people would scream. But because
construction site runoff is gradual and not as obvious,
builders get away with it.

Lance Schmidt is a builder. But he’s not your typical builder.
They used to call him a “tree-hugger builder.” These days
he’s seen as a trend setter.

Schmidt says nobody in the building industry is talking much
about construction silt.

“Believe me, stormwater’s not a fun issue to talk about. (laughs)”

But it’s one of the biggest pollution problems in creeks and
rivers.

Schmidt’s crew just dug a hole for the foundation of a small
house. He’s climbs up on one of four mounds of dirt. He
knows when it rains, some dirt can get washed away, and
end up in a nearby river. That’s why he puts up sediment
barriers. But most of the time no one checks to see if he
does.

“There aren’t any regulations as far as I know. I mean other
than if somebody was to complain.”

The Environmental Protection Agency in Ohio says it does
regulate construction sites. But, usually just the larger ones,
where there might be problems. The homebuilding industry
doesn’t really think it’s the problem.

Vince Squallice is director of the Ohio Homebuilders
Association.

“Construction and earth disturbing activities in construction is
not causing the siltation problem in Ohio.”

Squallice says farmers are mostly to blame for dirt runoff in
the rivers. It’s true that sediment runoff from farms is a huge
problem. But the EPA says sediment runoff rates from
construction sites are typically 10 to 20 times greater than
from farmland.

Squallice says builders already have to deal with too many
regulations such as setbacks from streams.

“Some of the regulations recommended to protect streams go
overboard in terms of environmental protection.”

Squallice says because of the housing bust, it’s a time to
help homebuilders, not enforce more environmental
regulations.

Builder Lance Schmidt says homebuilders need to look at it
a little differently. They can help solve a problem, keep
streams clean, and help cities with flooding problems.

“And that’s the avenue that I’ve decided to attack at. Rather
than attack the regulations, let’s sit back and find ways that
we can actually do this.”

Schmidt says there are lots of creative building ideas that
can reduce flooding, and improve the rivers for fish and other
wildlife. But in this competitive market, builders won’t do it
until everyone has to play by the same rules. And he
doesn’t expect that to happen without better enforcement by
regulators.

For The Environment Report, I’m Julie Grant.

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Paying for Ponds to Stem Farm Runoff

  • Alan Roberson's pond traps sediment. Before the pond was built, silt washed into a creek and caused problems farther downstream. (Photo by Lester Graham)

Since the dust bowl days of the 1930s Depression, the government has been working with farmers to reduce erosion. Today, soil conservation is better. But fields still lose a lot of topsoil because not all farmers use the best conservation methods. Dirt is washed away by rain. That silt clogs up streams, rivers and lakes. But one region is trying to intercept the silt before it gets to the river system. The GLRC’s Lester Graham reports:

Transcript

Since the dust bowl days of the 1930s Depression, the government has been working with
farmers to reduce erosion. Today, soil conservation is better. But fields still lose a lot of
topsoil because not all farmers use the best conservation methods. Dirt is washed away
by rain. That silt clogs up streams, rivers and lakes. But one region is trying to intercept
the silt before it gets to the river system. The GLRC’s Lester Graham reports:


Farm fields in all or part of 38 states drain into the Mississippi River. Some of the
tributaries of the Mississippi are so silted that dredges have to operate around the clock to keep river
shipping lanes open.


The Sangamon River in central Illinois is not big enough for shipping cargo, but it does
run into the man-made Decatur Lake. The city of Decatur gets its water from that lake
and often has to dredge it to keep the water inlets from clogging up.


Keith Alexander is the Director of Water Management for the city of Decatur, Illinois.
He says a little soil erosion on enough farms adds up:


“And the drainage area that runs into the lake is 925 square miles of some of the world’s
best topsoil. We have literally a half-a-million acres of corn and soybean fields that flow
into our lake that we use for drinking water purposes.”


Not only does the silt clog the lake, it also carries fertilizers and pesticides with it,
polluting the lake. The city has offered farmers financial incentives to reduce soil
erosion. But it hasn’t gotten enough participation from farmers to solve the problem. So,
the City of Decatur decided to try another approach. They would offer money to landowners to build ponds. Those ponds would be located in key drainage areas next
to farm fields.


Shannon Allen is a watershed specialist with the Macon County Soil and Water
Conservation District. He says it turned out to be a pretty popular program:


“The landowners wanted it for recreational purposes, obviously fish, maybe swimming
or whatever. We’re putting them in so we can collect sediment from the farm fields
above them so they don’t go into the river system.”


Shannon Allen says the ponds work a lot better at keeping silt out of creeks and rivers and lakes
than other methods to reduce erosion.


“Basically ponds collect 90% of the silt. And, so anytime you can put up a pond, you’re
doing better than a grassed waterway or a terrace that don’t reduce sediment loads by that
much.”


The city offers up to 5,000 dollars to landowners, but that’s well short of the actual cost. A typical pond
can cost 20 to 25,000 dollars to build. But landowners have been taking the city’s offer.


Alan Roberson owns a few acres at the bottom of a sloping corn field. About 42 acres
drains onto his property and then into a creek. He says when he moved there, there was
just a big ditch where stormwater from the neighboring farm fields washed a bigger and
bigger gully, carrying sediment to the creek:


“There was places eight, ten feet deep. We’ve lived here almost 20 years and it just kept
getting deeper as it went along. I hated to even come down here and look at it because it
was getting so bad. So, I’m glad that program came along to take care of it. As you can
see, it’s not doing that anymore.”


Roberson took advantage of the city’s pond program. Where the gully used to be, a carpet
of green lawn now borders a picturesque little pond.


Alan Roberson says the pond has a pipe in the bottom of it, kind of like a bathtub plug. It
was part of the design required to get the matching funds from the city. When the pond
fills up with silt, Roberson will be able to drain it and dig out the soil:


(Sound of water trickling)


“See this valve down here? You can actually pull that up. It could very well be 20 years
from now they’ll get enough silt in here where a person will have to bring it down. But
like I said, it’s designed to do that.”


That silt is some of the richest dirt in the corn belt and could be sold back to farmers or
used for gardens or flower beds. The landowner will have to pay the cost of digging it
out, but it’s that much more silt that won’t have to be dredged from the lakes or the rivers
that feed them, where people get their public water supply.


For the GLRC, this is Lester Graham.

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Dam Removal’s Balancing Act

  • The continued operation of hydroelectric dams will be up for debate in the next decade. Currently, the Army Corps of Engineers is looking to remove the Boardman River dam in northern Michigan. This dam removal could impact how all future dam removals are completed. (Photo courtesy of the Michigan Department of Natural Resources)

The Army Corps of Engineers is tackling a dam removal project that could affect how the Corps approaches future dam removals. In the next decade, communities will be deciding whether to keep operating tens of thousands of hydroelectric dams on rivers across the country. This project is significant because it involves several dams being taken out of production along the same stretch of river. The GLRC’s Bob Allen reports:

Transcript

The Army Corps of Engineers is tackling a dam removal project that
could affect how the Corps approaches future dam removals. In the next
decade, communities will be deciding whether to keep operating tens of
thousands of hydroelectric dams on rivers across the country. This
project is significant because it involves several dams being taken out of
production along the same stretch of river. The GLRC’s Bob Allen
reports:


(Sound of water)


The Boardman River is beautiful. It winds and turns and tumbles
through forested hillsides and passes along northern cedar swamps.
Sections of the upper river qualify as a blue ribbon trout stream, but a
series of dams along the lower half of the river changed some of the best
river water.


Steve Largent has worked on repairing damaged banks along the
Boardman for the last fifteen years. He says removing the dams will
restore faster flowing sections of the river, and clearing out the sand and
silt built up behind the dams will be good for trout and other critters.


“The sediment that is building up in the back of Brown Bridge pond
continues to move upstream as it fills in the upper end of the pond it’s
aggregrating upstream. It’s moving upstream further and further destroying
habitat further upstream.”


So a free running river will help wash away that sediment, but these days
it’s not just anglers who are interested in the Boardman River. Recently
river engineers have been drawn to the Boardman like trout to a fly
fisherman’s lure. They’re interested in landing the job of studying the
Boardman River and its dams. The million dollar study will look at
whether to keep or tear down three hydroelectric dams along a 17 mile stretch of river in northern Michigan just before it flows into Lake
Michigan.


Craig Fischenich is a research engineer with the Army Corps of
Engineers. He says the potential to remove three dams along the same
stretch of river is not something you’re going to find anywhere else.


“Whereas in many parts of the country they’re removing individual dams, they’re on systems that have other dams on them, and so this is an
opportunity here to actually try to restore an entire watershed.”


Fischenich says taking out the dams would mean improvements for
native fish. But there are risks too. If the dams go, invasive species
such as the parasitic sea lamprey could get upriver, and introduced
species such as steelhead and salmon could swim into the river and
compete with the native fish.


That prospect doesn’t exactly thrill John Wyrus, who lives on the
Boardman. He’d rather see some kind of obstacle down near the mouth
of the river to prevent introduced species from entering.


“So that these steelhead and salmon can’t get up the river. I would just
like to see it a brown trout and brook trout fishery.”


That’s the kind of scenario the study of the Boardman River would
consider.


(Sound of people talking)


Recently a lot of the engineers vying to do the study gathered at a
conference put together by the Corps of Engineers.


Gordon Ferguson works for ENSER Corporation. His company
is one of a dozen that submitted bids to land the study.


“This is a particularly interesting project because it involves a lot of
complex issues both from an engineering standpoint and also local
community issues. Property rights issues of homeowners along the
watershed.”


What they learn from the Boardman could be important to communities
near rivers across the nation.


Many of the tens of thousands of dams across the country are aging, and
in coming years, just like on the Boardman River, those with hydroelectric generating stations will need to be upgraded to keep their operating license.


The local utility says the dams on the Boardman don’t generate
enough power to make it worth fixing them. So they’re giving up the
licenses to generate electricity. Ownership of the dams reverts to the
local governments, and local officials are asking the Army Corps of
Engineers to pay for the study of the Boardman. The federal agency is
eager to be involved in this project.


The Boardman River study offers a chance for researchers to figure out
how to count less tangible values. Like how removing dams will affect
other wildlife such as eagles and osprey along the river.


Jock Coyngham is an ecologist for the Army Corps of Engineers.
Typically, he says, wildlife and recreation get discounted in this kind of
study because it’s easier to quantify things like hydropower, but it’s
important to figure out what value they have.


“If you make all your resource decisions as a state and as a country over
a long period of time pretty soon there won’t be any substantial fish
populations, any wild reproduction. Just because traditional cost-benefit
analysis tends to underestimate those ecosystem services and values, let
alone aesthetics.”


The Army Corps is waiting final approval for funding. Once given the
OK, the study of the Boardman River and its dams… could very well lay
the groundwork for other dam removals around the country.


For the GLRC, I’m Bob Allen.

Related Links

Ballast Slime Hatches Aquatic Invaders

New research shows that having ships dump their ballast water before entering the Great Lakes might not be enough to stop the growth of invasive species in the region. The Great Lakes Radio Consortium’s Lester Graham reports:

Transcript

New research shows that having ships dump their ballast water before entering the Great Lakes might not be enough to stop the growth of invasive species in the region. The Great Lakes Radio Consortium’s Lester Graham reports:

Freighter ships are now required to exchange their ballast water in the ocean before entering the Great Lakes to flush out aquatic nuisances that might have hitchhiked from foreign ports. But a biology student at the University of Windsor, Sarah Bandoni, has found that the slime and silt at the bottom of the ballast tanks carry lots of eggs. That silt isn’t all removed when the water is flushed. And, despite having been in dark and freezing conditions, when things become better, the eggs can hatch.

“In the most part, I’m finding quite a lot of them are viable, averaging probably 50 to 75-percent of the eggs have been able to hatch.”

Bandoni says that means there’s at least the potential for some of these eggs to escape into Great Lakes ports. About 160 invasive species, such as the zebra mussel have been imported by cargo ships, causing damage to native species, including fish.

For the Great Lakes Radio Consortium, this is Lester Graham.

Long Term Impacts of ’93 Flood

The Mississippi River is changing. Some fish and wildlife that once
lived in or around the river are gone and other plants and animals are
moving in. The Great Lakes Radio Consortium’s Lester Graham reports
researchers are finding that the flood of 1993 has accelerated those
changes:

Discovering Impacts of the ’93 Flood

  • Like many other trees that produce food for wildlife, this pecan tree died after the '93 flood.

It’s been more than five years since the great flood of ’93 hit the
upper Mississippi River and its tributaries. Since then towns have been
moved to higher ground. New levees have been built. And… people —for
the most part— have recovered from the damage. The Great Lakes Radio
Consortium’s Lester Graham reports that researchers are finding the
long-term damage has been to the environment:

New Ideas for Sediment Removal

The Corps of Engineers spends hundreds of millions of dollars each year
dredging harbors and river shipping channels nationwide to keep them
open. For more than 30 years conservationists have been yearning for
ways to do more than just keep barge canals open. They want to save
vulnerable river backwaters and ever-shallower lakes. Until recently
there has never been a technology capable of moving the amount of
sediment at reasonable costs while keeping the environment safe. But,
as the Great Lakes Radio Consortium’s Charlie Schlenker reports, that
may be changing:

Wetlands Sedimentation a National Problem

Conservation agencies are having a tough time correcting one of the
worst problems in some on the most sensitive areas. The Great Lakes
Radio Consortium’s Lester Graham reports on the damage sediment and silt
have on wetlands:

Proposed Cuts May End Harbor Dredging

Maintenance of small recreational harbors on the Great Lakes could
be cut if the Army Corps (CORE) of Engineers has to trim its budget any
further. This month (October, 1998), Congress rejected a Clinton
Administration request to stop dredging small harbors. The Great Lakes
Radio Consortium’s Mike Simonson has the story: