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The
upper Mississippi River, which starts at Lake Itasca in northern Minnesota, is
in great shape until pollutants flow in from farmland and cities. By the time
it reaches Minneapolis, it no longer meets water quality standards for river
life and recreation. Results from a new study by the Minnesota Pollution Control
Agency (MPCA) highlight the need to protect wetlands and forests in the iconic
river’s northern areas while taking action to curb pollution in its southern
reaches.
It’s hard to overstate the river’s importance as a drinking
water source to millions of Minnesotans and Americans downstream.
The river is nearly pristine as it flows through forests,
wetlands and lakes until the land changes to cropland and cities. South of St.
Cloud, pollutants start to pour in with runoff, drainage and tributaries. These
pollutants include sediment that clouds the water; nutrients that cause algal
blooms; and bacteria that can make the water unsafe for swimming.
“What we do on the land is reflected in
the water,” said MPCA Commissioner John Linc Stine. “This study underscores
that point.”
The study shows the northern reaches of
the upper Mississippi are healthy, thanks to the forests, wetlands and lakes
that hold and filter the water flowing to the river.
“But these areas face increasing threats
like forest or other land conversions for agriculture and development. Whenever
land goes from a stable and vegetated state without protections in place, water quality will go
down. That’s the lesson of history,” said Stine.
While the upper reaches need protection to
keep the river healthy, the lower reaches need large-scale changes to reduce
pollutants. After the Crow River flows into the Mississippi, phosphorus and
nitrate pollution double in levels. The Crow drains a heavily farmed area and
makes up about 15% of the total land area draining to the upper Mississippi in
Minnesota.
“Thanks to groups like the Crow River
Organization of Water, watershed districts, and soil and water conservation
districts, work has already started to curb this pollution. But we all need to
do more. We need more buffers, better use of fertilizer and manure, and more
conservation on farmland and urban land,” said Dana Vanderbosch, manager of
lake and stream monitoring for the MPCA.
The study also highlights the need to
protect the upper Mississippi as a source of drinking water. Nitrate can make
water unsafe for drinking. While levels are currently well below the threat
level, water monitoring shows a trend of increasing nitrate levels, a concern
for the 1.2 million Minnesotans who depend on the upper Mississippi for drinking
water, as well as millions farther downstream.
It’s also important to continue efforts to
decrease mercury levels in Minnesota waters. Mercury levels in fish and in the
water in the entire upper Mississippi violate the consumption standard. This
means guidelines will remain in place on how much and what size of fish to eat.
Many
projects are underway at the state and local levels to ensure that the Upper
Mississippi meets the standards for river life, recreation and fish
consumption.
“The
future health of the Mississippi River will depend on the ability of these
projects to protect healthy conditions and reduce pollutant loads so that future
generations can enjoy this invaluable resource,” Vanderbosch said.
About
the study
As part of assessing the health of major
watersheds across Minnesota, the MPCA studied the 510 miles of the upper
Mississippi from Lake Itasca to St. Anthony Falls in Minneapolis. Scientists
measured levels of pollutants such as sediment, nutrients, bacteria and
mercury. They also studied populations of fish and other aquatic life such as
insects. Using data from nearly 200 monitoring stations along the upper
Mississippi, from many partners and spanning 10 years, the agency determined
whether several sections of the river met water quality standards.
The agency and local partners conduct more
detailed monitoring of the upper Mississippi, and the 20,105 square miles draining
to it, at a smaller scale known as major watersheds. These watersheds are areas
of drainage to tributaries or the Mississippi.
For more information, visit the study
webpage at www.pca.state.mn.us/upper-miss.
Broadcast version
The
upper Mississippi River, which starts at Lake Itasca in northern Minnesota, is
in great shape until pollutants flow in from farmland and cities near St.
Cloud. By the time it reaches Minneapolis, the Mississippi no longer meets
water quality standards for river life and recreation.
These
are the results of a new study by the Minnesota Pollution Control Agency. Its
findings highlight the need to protect wetlands and forests in the
Mississippi’s northern areas while taking action to curb pollution in its
southern areas.
It also highlights the need to protect the Mississippi as a
drinking water source for millions of people in Minnesota and downstream.
Levels of nitrate, which can be unsafe for humans and aquatic life like fish,
are well below the water quality standard. But levels are increasing in the
river.
For more information, visit the agency website at www.pca.state.mn.us and search for “upper Mississippi.”
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The mission of the MPCA is to protect and improve the environment and enhance human health.
St. Paul • Brainerd • Detroit Lakes • Duluth • Mankato • Marshall • Rochester • Willmar
www.pca.state.mn.us • Toll-free and TDD 800-657-3864
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