Spielman Associate Editor
Winona, Minn. — A larger than normal portion of Mississippi
River floor will see the sun again this summer. State and federal
officials say a drawdown of Pool 5 is scheduled to occur for the
second year in a row.
The drawdown is meant to mimic river action prior to the lock
and dam system, when exposed land meant greater plant development,
which benefits fish and wildlife.
“It sure looks like (drawdown will occur in the pool this
summer),” said Mark Andersen, Mississippi River wildlife biologist
for the Wisconsin DNR. “We held a couple public meetings in the
area, and there’s good support for trying it again this year.”
Like 2005, Andersen said agencies involved with the project
would attempt to draw down Pool 5 about a foot and a half. The
drawdown would begin June 12 and end in mid-September.
Officials from the U.S. Army Corps of Engineers weren’t certain
if the full 18 inches would be realized. The vast majority of the
project’s cost – main channel dredging – was completed this year,
with hopes that the dredged area would remain open and allow the
river lowering in 2006. That’s yet to be determined. The cost last
year for that dredging was estimated to be about $1 million.
However, Mary Stefanski, Winona District manager for the U.S.
Fish and Wildlife Service, says preliminary indications are there’s
been minimal accumulation from last year.
Andersen said while the water flow through Pool 5 makes it
conducive to drawdown, there also are rivers and streams that enter
the Mississippi at the pool that increase the amount of sand
entering the river – increasing the need for dredging.
Pool 5 is the second Mississippi River pool along the
Minnesota-Wisconsin border that’s experienced a drawdown; Pool 8
was drawn down for consecutive years in 2001 and 2002. Other pools
are being considered, including pools 9, 6, and 3.
Like it was in Pool 8, Stefanski said the second year of the
drawdown will be crucial for proper plant development in Pool 5.
The first year gave some important plant species, such as arrow
weed, a chance to become established, the second year gives it –
and other submergent plants – a chance to thrive.
These plants stabilize shoreline soil and improve nesting
habitat for waterfowl species, Andersen said. Also, the plants –
which produce tuber (potato-like) roots – provide an important food
source for wildlife like muskrats and swans.
Last year, the drawdown resulted in the first time some of the
pool’s substrate had been exposed in some 70 years. About 900 acres
of river bottom saw the sun. Some river interests had supported a
drawdown greater than 18 inches (up to 2 feet), but funding wasn’t
available to support that level.
The drawdown efforts receive input from border states including
Minnesota, Wisconsin, and in some cases, Iowa and Illinois. Also
involved are the USFWS, the U.S. Geological Survey, and the Army
Corps of Engineers. Conservation groups also have had a say in the
matter, and public input has been taken during each phase of the
Stefanski said officials continue to monitor the results of
efforts from Pool 8. The USGS is conducting most of that
monitoring. River users are noticing the benefits, too, she
“People are requesting drawdowns on ‘their’ pool of the river,”
she said, adding that “every pool has its own constraints.”
Pools 8 and 5 were picked for a number of reasons, including how
many acres would benefit from a drawdown.