City environmental inspectors measure impact of pollution on the Mississippi
On a sunny, early fall morning, Steve Kennedy propels a tan fishing boat across the calm, leaf-speckled surface of the Mississippi River.
The riverbank blooms bright autumn yellow as the craft floats past the tagged-up belly of a railroad bridge to its destination, an out-of-the-way nook hidden behind Nicollet Island.
Kennedy steadies the boat next to a concrete storm sewer pipe by grabbing a spindly branch about the width of his graying, braided ponytail. His crewmate, Alison Fong, then flips open a black tackle box, removes a plastic bottle and begins filling it from the slow trickle splattering off the drain's lower lip.
Kennedy and Fong, environmental inspectors with the city of Minneapolis, are collecting data for an ambitious water quality study that will eventually show how much Minneapolis is responsible for polluting the river. And the results could prove valuable in the city's compliance with expected federal water quality enforcements on the river in the coming years.
A strip of masking tape wrapped around the bottle shows the date and location for the water sample. Once it's full, Fong, with a short, thick tail of dark hair jutting from the back of her khaki baseball cap, seals the container, drops it in a zip-lock bag and places it in a cooler for safe-keeping. They'll need to get the samples to a laboratory within a few hours so technicians can begin testing for bacteria and chemicals.
About 200 storm drain outfalls empty into the Mississippi as it passes through Minneapolis. Whenever rain or snowmelt flows into street gutters, it picks up all the fertilizer, pet waste, motor oil, grass clippings, and other litter in its path and washes it through underground sewers directly into the city's lakes, streams and rivers.
“It doesn't get treated first,” Fong said. “The biggest thing people don't realize is that what runs into the gutter goes right into the river.”
The city entered a partnership with the Mississippi Watershed Management Organization last year to begin testing outfalls for things like e. coli bacteria, fecal matter and phosphorus - all indicators of the river's health. The watershed group will pay $71,000 over the next decade to cover laboratory, consulting and other costs. In exchange, the city will share data, software and equipment, including the installation of four automated water-sampling stations.
The staff is winding down its first full season of sampling and expects to compile some preliminary results over the winter, Kennedy said. But it will take a few years to determine a baseline, or what's typical, so regulators can measure improvements in the future.
“We don't know what is the contribution coming out of those pipes,” said Doug Snyder, director of the watershed organization, a joint-government agency whose members are cities with land that drains into the Mississippi River.
‘Goldmine' for pollution
Storm water runoff is a major source of water pollution, and it doesn't always take a microscope to see its affects on the river. As Fong and Kennedy collected another sample upstream, an electrician, Jeff Jarosz, hollered down as he repaired a navigation light: “That's a goldmine, isn't it?” After heavy rains, Jarosz said he's seen tugboat crews dangling fishing nets under the outfall, catching one-, five- and 20-dollar bills as they spilled out with a mess of tennis balls, used condoms and other assorted trash flooded out of gutters.
The outfalls study is measuring smaller and more telling indicators. It's looking at the amount of bacteria, soil and sediment, and nutrients like phosphorus that spill out of each storm drain into the Mississippi.
“Our main concern right now is the e. coli bacteria and fecal coliform,” said Kari Oquist, an environmental technician with the Mississippi Watershed Management Organization.
Certain e. coli strains are associated with food poisoning. The type water quality monitors test for is harmless, but it indicates the presence of human or animal feces, which can make people very sick if swallowed. In rural areas, fecal matter leaks into water supplies from agriculture and animal feet lots. In cities, it comes from pet and wildlife waste, as well as improperly connected sewer pipes, Oquist said.
They're also measuring sediment - all the dirt, sand and debris that washes into the river, clouding the water and wiping out habitat for the smallest, bottom-dwelling bugs. The tiny creatures play a critical role at the base of the food chain, said Trevor Russell, watershed program director for Friends of the Mississippi, a nonprofit advocacy group. Fish can also struggle in murky waters, too, he said.
“It's very hard for them to handle turbid water. They can't see. They can't navigate. They can't see prey,” Russell said.
Turbidity is a measure of how clear water is, or how easily light transits through it. Algae or soil in the water make it difficult for sunlight to pass through, making it difficult for aquatic life to survive.
Another indicator is phosphorus. The chemical, found in fertilizers and also naturally occurring in the environment, is food for algae. When it settles in a lake, algae blooms can drain a water body of its oxygen and light, starving other aquatic life. Grass clippings release phosphorus as they decompose, so letting them run into the street can contribute to algae outbreaks downstream.
“In the perfect world, all that would be discharged is nice, clean rainwater,” said Tom Frame, a supervisor with the city's Environmental Management and Safety department.
More than 80 percent of the Mississippi River from its headwaters to the Quad Cities in Iowa is classified as impaired by the U.S. Environmental Protection Agency. That means those areas have unsafe levels of at least one pollutant. The most recent state water quality report shows the segment running past Downtown has unacceptable concentrations of mercury, PCB and bacteria.
“It certainly has been improving over the past several years,” Larson said, but it has a long way to go, too.
The Clean Water Act, passed by Congress in 1972, requires that states monitor water quality and take steps to ensure all lakes, rivers and streams are safe for aquatic life and recreational activities like swimming, fishing and boating. When water is identified as unhealthy, states are supposed to study the underlying causes and enact programs or enforcements to repair it. Enforcements can include tighter restrictions on discharge permits, including the permits required by cities for storm drain systems.
Minnesota, like all states, is far behind schedule when it comes to studying the causes of pollution and drafting recovery plans. A major study is underway on Lake Pepin, though, with potential to affect communities along the Mississippi, Minnesota and St. Croix rivers, as well as their tributaries, all of which flow into the lake.
“It was a logical way to really start addressing what's happening in all of those watersheds,” said Tim Larson, metro-area water investigation coordinator with the Minnesota Pollution Control Agency.
Lake Pepin, a natural lake on the Mississippi River southeast of the Twin Cities, was placed on the impaired waters list in 1998 for excess nutrients, mostly phosphorus, and turbidity.
A study to identify the causes of the Lake Pepin pollution started last year and is scheduled to be completed by 2009. It's expected some of the causes will point back to Minneapolis storm water outfalls.
“At some point, there will be orders to communities upstream to reduce sediment,” said Snyder.
When the Lake Pepin study is complete, the state has authority to place restrictions on discharge permits. The city might, for example, be ordered to upgrade its systems or install expensive equipment to reduce pollution.
The information collected in the city outfall testing will help the state figure out how much responsibility to assign the city for Lake Pepin's condition, Larson said. The city will also be able to use it to measure required improvements.
“If they didn't do this now, we wouldn't have as good of information about exactly what's coming out of the system,” Larson said.
Lori Olson, deputy director of the city's Environmental Management and Safety department, said the city doesn't plan to sit and wait. Getting involved in the Mississippi River outfalls study was an effort to be proactive.
Residents don't have to wait for the studies to be completed before they take action to help the river, either.
“We're not done yet, but we're certainly on the right path,” Larson said.
Dan Haugen can be reached at [email protected] and 436-5088.