A car sits in a sinkhole that formed at the corner of Oakland and North avenues.

A massive rainstorm in July 2010 turned city streets into rushing rivers and infamously created a sinkhole so big at N. Oakland and E. North avenues that it swallowed a Cadillac Escalade.

But the flood brought more than rain. It also carried an immense dose of pollutants that washed into waterways.

Big storm events are growing more common. On the Milwaukee River alone, four of the 10 biggest recorded floods have occurred since 1997, according to the Southeastern Wisconsin Regional Planning Commission.

But even with gentle rains, urban and rural runoff is the biggest source of water pollution remainingtoday.

And it is the primary reason many sections of Milwaukee's rivers remain polluted and fail to meet state water quality standards — despite $5 billion in government spending since 1980, a Milwaukee Journal Sentinel analysis found.

The analysis shows there is a trend of improving water quality in areas that have combined storm and sanitary sewers — mostly in central Milwaukee, where the Milwaukee Metropolitan Sewerage District captures and cleans polluted runoff before it reaches waterways.

In other areas, water quality has changed little and, in some cases, has grown worse, with much of it due to runoff — the dirt and road salt from streets, oil and grease from parking lots, fertilizers, pesticides, eroded soil, and feces from pets and livestock that flow into streams and rivers, and eventually Lake Michigan.

While the rivers carry much less municipal and industrial waste than before billions of dollars were spent on cleanup because of the Clean Water Act, there is no clear-cut improvement in many key measures of water pollution, an analysis of government data over the past three decades by the Journal Sentinel shows.

Bacteria levels have been falling. But a pollution measure strongly influenced by the application of road salt is getting worse.

The Clean Water Act of 1972 required factories and wastewater treatment plants — known as point sources — to limit the amount of pollutants they can release into public waters.

Under the law, cities must also reduce pollutants in storm water. Street sweeping and green infrastructure projects designed to capture rainwater help. But much of the grit and grime — known as nonpoint pollution — escapes any type of controls.

Runoff troubles are exacerbated by an ever-growing expanse of roads, rooftops, sidewalks and parking lots that help carry pollutants faster to rivers and streams. Twenty-three percent of the Milwaukee River watershed is devoted to urban uses. It jumps to 60% on the Menomonee and to 83% on the Kinnickinnic, according to the regional planning commission.

"The focus for too long has been on industry," said Karen Schapiro, a former executive director of Milwaukee Riverkeeper, an environmental group focused on the region's watersheds, who now teaches law at Marquette University. "Nonpoint (pollution) has been largely exempt from regulatory requirements, and that has got to change."

Changes over the years

Photo Gallery The MMSD river skimmer called Lynyrd Skymmr collects trash and tree branches and other debris from the Milwaukee River north of Wells St. on the first day of the 2013 cleaning season for the skimmer. Photo Gallery: Looking at rivers' water quality

Every spring, thousands of volunteers at Riverkeeper's annual cleanup fan out to spots on the Milwaukee, Menomonee and Kinnickinnic to pick up trash. The cleanup gets corporate sponsors, and debris is carted off by the Dumpster load — signs of growing public enthusiasm for the health of rivers.

But such efforts make only a dent.

The state Department of Natural Resources says 53% of the nearly 900 square miles ofrivers and streams in the greater Milwaukee basin assessed by the agency fail to meet standards for phosphorus, E. coli or polychlorinated biphenyls, known as PCBs.

Phosphorus can speed plant and algae growth. E. coli is a bacteria associated with feces, and PCBs are an industrial chemical once used by local manufacturers but now banned.

"Everyone is trying to grapple with how best to tackle the problem," said Matt Moroney, deputy secretary of the state Department of Natural Resources. "I think it underscores the complexity of the problem.

"This is not just a Milwaukee problem."

Milwaukee Riverkeeper uses volunteers to conduct its own water testing, using protocols accepted by the DNR. The grade from its most recent report card for the greater Milwaukee basin in 2012:

A C-minus, with the lowest marks given to the Menomonee and Kinnickinnic rivers.

"We'd like to be further along, obviously," said Cheryl Nenn of Milwaukee Riverkeeper. "If we hadn't spent the money, things would have been much worse and most of the trends would be much worse than they are now."

The Kinnickinnic, Wisconsin's most urbanized waterway, is in the worst shape, regulators and environmental groups agree. Based on historic vegetation surveys, the DNR believes the Kinnickinnic has lost 93% of its wetlands, which act like a sponge to prevent flooding and filter water.

Still, our rivers look nothing like a century ago when a growing city and its manufacturing base molded the river to meet its needs and dumped waste in every form.

By some accounts, the vast wetlands of the Menomonee Valley were gone by 1900.

Video Volunteers took to the shores of the Milwaukee, Menomonee and Kinnickinnic rivers in April as part of the Milwaukee Riverkeeper's annual spring cleanup.

What got thrown into the water? At twilight last fall, historian JohnGurda stood before a crowd near the Mitchell Park Domes and read from a Milwaukee Sentinel reporter's observation in 1886.

"Rotten potatoes and fruit, the contents of haunches and entrails of animals, the refuse of meat shops, and all sorts of filth are deposited in the marsh," Gurda read.

Then he described the valley's transformation from train tracks and factories to new industry, the addition of Miller Park, Potawatomi Bingo Casino, the Hank Aaron Trail and a new park.

Afterward, hundreds of people walked through Three Bridges Park, which opened in July 2013, and watched performers of Wild Space Dance Company dance over a former rail yard that has been sculpted and sloped to the river. Geese flew overhead and the din of freeway traffic groaned in the distance. The program, a celebration of urban wilderness, ended as water rushed past wading dancers and a floating bonfire drifted downstream.

The crowd cheered.

What's polluting the water

How to read the charts

3. Milwaukee River at Wells St. Fecal coliform is trending down. It’s a form of bacteria from feces. The sewerage district’s deep tunnel system has helped reduce fecal levels. The chart shows the percentage of fecal coliform tests that exceeded 400 coliform units per 100 milliliters, a benchmark for acceptable river health.

Water quality shows ups and downs Water quality is generally improving in the great Milwaukee basin, but the situation changes at different locatiosn and with different water measures. The points on the map correspond to the accompanying charts. Source: Journal Sentinel analysis of MMSD data

One of the most common ways to judge the health of a river is to measure what's in it.

The Journal Sentinel examined the records of tests of thousands of water samples from MMSD at points on the Milwaukee, Menomonee and Kinnickinnic from 1981 to 2013. The sewerage district keepsthe most extensive source of data in the region. Some of the key findings:

Fecal coliform. The biggest sign of improvement is the measure for fecal coliform — a form of bacteria from feces that is an important measure of whether water is safe for swimming. Levels have dropped in most spots where the rivers were tested.

Officials attribute recovery to the decline in combined sewer overflows since the deep tunnel project went into operation in 1994. The tunnels capture sewer and polluted storm water until it can be treated.

Spikes in fecal bacteria are normally associated with wet weather because of manure runoff, failing septic systems or surges in fecal waste from wildlife and pets. Despite the progress, there are still days, normally during and after rains, when bacteria levels skyrocket.

2. Milwaukee River at North Ave. Road salt concentrations are increasing. This can be harmful to aquatic life. The rise is due to growing use of salt in winter. Scientists use conductivity to measure road salt and other properties in water. It’s a measure of water’s ability to pass a current.

Road salt. A measure for road salt — known as conductivity — is getting worse almost everywhere. Conductivity measures the ability of water to pass an electric current. It is influenced by various pollutants, including chlorides, or road salt. The higher the chloride level, the easier to pass a current. At elevated levels, chlorides can inhibit plant growth, slow reproduction and reduce diversity of aquatic life.

The highest is on the Kinnickinnic, where it peaks at S. 27th St. along the Kinnickinnic Parkway.

The City of Milwaukee applied an annual average of 13.2 tons per lane mile of road salt between 2003 and 2013. That's about twice what Madison applied, data from the cities shows.

The figuresdon't reflect salt use by homeowners and businesses. Even with Madison's low-salt diet, chloride levels continue to rise in its local waters, according to a 2012 study by Roger Bannerman, a water resources management specialist with the DNR who is now retired.

Road salt doesn't go away quickly and can remain toxic long after winter ends. Computer modeling by the U.S. Geological Survey, using MMSD water data between 2006 and 2010, shows that sites on the Menomonee exceeded the federal standard for chloride on average on 261 days a year; on the Kinnickinnic it exceeded the standard on 294 days, or 81% of the time.

Road salt, however, also makes roads undeniably safer.

"It's a big complex problem, because there's some urgency to it, but we have to balance the social benefits with the environmental evils," Bannerman said.

Communities are looking at other options, but Bannerman said road salt remains the top choice because it's the cheapest. Beet juice is being used as a brine solution to make salt absorb on roadways, but it adds phosphorus to waterways. Other options such as chemically formulated calcium chloride are more corrosive on roadways.

Bannerman believes the best approach, long term, is to help motorists adjust their expectation to driving on roads with less salt, without compromising safety; reduce municipal salt use in residential areas; and persuade property managers and homeowners to moderate salt use.

1. Milwaukee River at Pioneer Road Nitrate levels are rising — a situation that can spur excessive plant growth. Nitrates are a form of nitrogen that comes from fertilizer, manure and failing septic systems. It’s heavily influenced by rural land use practices.

Nitrates. All sections of the Milwaukee — the river most influenced by agriculture in the region — showed increases in nitrates. The pollutant is heavily affected by how much of it is used in farming. Conditions improved or worsened, depending on the location, on the Menomonee and Kinnickinnic.

At elevated levels, nitrates can spur excessive plant growth and reduce oxygen in water. At high levels, it can be toxic to some wildlife.

Nitrates, a form of nitrogen, come from fertilizer, manure storage systems, failing septic systems and effluent from wastewater treatment plants. The DNR says there has been a lack of focus in the farm sector in controlling nitrogenuse as fertilizerfor crops like corn.

"We're seeing a trend of increasing nitrates all across the state, especially where agriculture is present," said Matt Diebel, a research scientist for the DNR.

Total phosphorus. Levels of phosphorus have dropped at most sites over the past decade.

Phosphorus spurs algae and weed growth and comes from farm fields, grass and leaves, animal waste and sewer overflows. It was banned from laundry detergent in the 1970s in Wisconsin and removed from dishwasher detergent and most lawn fertilizer in 2010.

The DNR says periodic spikes in phosphorus suggest the need for more controls from runoff sources. But because it clings to soil, it could take years to see improvement.

The DNR and MMSD also say the phosphorus problem is aggravated by its use in drinking water by several local water utilities. In 1996, Milwaukee Water Works started adding a form of phosphorus to prevent leaching of lead in aging pipes. Other communities in the region do the same, including the utility governed by the North Shore Water Commission.

Some of the water enters rivers from facilities that use it to cool boilers and other equipment. In all, about 140 facilities discharge cooling water into the three rivers. The discharged phosphorusis under review by the DNR and MMSD, and officials say they will know more about its role as a source of pollution later this year.Regulators could impose limits in coming years.

"It's easy to point to Milwaukee Water Works, but the contribution we make to the environment is extremely small," said Carrie Lewis, the superintendent.

Total suspended solids. There are fewer particles suspended in the river currents — the water is generally less muddy. The tiny bits of sand, clay, soil, sewage, manure and other material can slow photosynthesis, clog the gills of fish and degrade spawning habitat.

While they are on the decline, there are numerous times when particle levels skyrocket, after big rains wash soil off cultivated fields, and grit and grime off streets and other hard surfaces. Street sweeping and the use of vegetative buffers along streams are helping control the problem.

4. Menomonee River at 25th St. Dissolved oxygen is getting better. As displayed in this chart, oxygen levels are rising, or improving. This is a key indicator of the health of a river. The standard for most rivers comparable to the Menomonee is 5 milligrams per liter. But state law permits the river to legally meet a lower standard with less oxygen: 2 milligrams per liter.

5. Kinnickinnic River at 1st St. Dissolved oxygen is below the standard of 5 milligrams per liter that applies to most rivers. State law permits the KK to legally get by with less oxygen: 2 milligrams per liter. At this level, bass and bluegills could not survive, but carp could.

Dissolved oxygen. Some sites show improving oxygen levels, necessary for aquatic life, especially where combined sewer overflows have been reduced. But other areas have changed little or deteriorated slightly. Regulators say oxygen levels are adequate to sustain most aquatic life at most locations and meet the state standard. The only exception, according the Journal Sentinel analysis, is the Kinnickinnic at S. 1st St.

"The river's absolutely cleaner than when I first came here," Ken Leinbach said during a walk in Milwaukee Rotary Centennial Arboretum, nestled between Riverside University High School and the Milwaukee River. As he ambled up a path from the river, Leinbach noted that the number of fish species, tiny water insects, crustaceans and other aquatic life has grown since the dam at North Ave. was demolishedin 1997.

In 2002, schoolchildren found the first water penny in the river, said Leinbach, executive director of the Urban Ecology Center. Water pennies are the aquatic larvae of a family of beetles. They are highly sensitive to pollution and are seen as indicators of good water quality.

"They're a bit like a canary in a coal mine," Leinbach said.

Fish advisories ease a bit

How Journal Sentinel analyzed MMSD data on water quality For this analysis of water quality, the Milwaukee Journal Sentinel examined more than three decades of data from a dozen testing sites along the Milwaukee, Kinnickinnic and Menomonee rivers. The data, provided by the Milwaukee Metropolitan Sewerage District, allowed a comprehensive look at how six measures of quality have changed. The district compiles and maintains some of the most extensive water quality data available for the region. Half of the sites for which data was examined fall inside the combined sewer service area, where MMSD captures and cleans polluted runoff before it reaches waterways. Half of the sites are outside the area — one on the Menomonee River near the border of Washington and Waukesha counties, for example, and another on the Milwaukee River in Ozaukee County. Examining the distinct groups of sites showed some of the effects major projects such as the deep tunnel system have had on bacteria levels and other metrics of water quality. The analysis covered water results between 1981 and 2013. Data was used from April through November to provide consistent results. In some years, ice cover made it difficult to obtain samples at some sites. Experts from MMSD, the state Department of Natural Resources and the Southeastern Wisconsin Regional Planning Commission reviewed the Journal Sentinel's analysis and provided comment for these articles. They emphasized the difficulty of analyzing pollution trends and discerning whether they were getting better or worse, from one year to the next. They agreed that larger trends are evident: Overall water quality is improving and more work to limit pollutants is needed.

At sites along the rivers, signs are posted that warn anglers about the potential toxic effects of eating fish because of industrial contamination from a family of chemicals known as polychlorinated biphenyls.

PCBs, a probable human carcinogen, were outlawed in 1979, but some of the chemicals eventually made their way to waterways, lodged in the sediments and were taken up by fish.

For the lower Milwaukee, advisories have improved for some fish, but not for carp, according to the DNR.

The state's fish consumption advisories for crappie, northern pike, red horse and smallmouth bass have become less restrictive. In the 1980s and 1990s, they recommended "do not eat." Now they range from one meal per week, to one meal per month or six meals per year, depending on the type of fish and locations on the river.

"There has been improvement," said Candy Schrank, toxicologist for the DNR. "It's just not huge."

John Mulhern's personal barometer of river health comes from the seat of his canoe.

He sees fewer shopping carts. Over the years, he's pulled out his share, plus a sink, a bathtub, a home safe and surveying equipment from a road project. And for the first time ever last year, he spotted midland smooth softshell turtles — a species of "special concern," a designation the DNR uses to focus attention on plants and animals before they become endangered or threatened.

Mulhern, 83, paddled different sections of the Milwaukee 237 times last year. A favorite trip is paddling solobelow the dam in Thiensville to Kletzsch Park near his home in Glendale.A retired bank examiner, he keeps track of his paddling on a piece of paper, erasing the last digit and writing in a new one with each trip.

"The river is getting cleaner," he said. "There's just a lot more going on. I see more people fishing. I see more birds. The river looks better."

Clean Water Act's role

The improvements have been due largely to passage of the Clean Water Act.

The goal of the act was to eliminate all pollutants discharged into waterways by 1985; an interim goal was to make all water safe for people, fish and wildlife by 1983.

"I think that a lot of the low-hanging fruit has been picked off," said Will Wawrzyn, a fisheries biologist with the DNR, who has spent more than 30 years working in the greater Milwaukee basin.

As laudable as the measure was, Congress "probably didn't recognize at the time how ambitious their goals were," said Schapiro, the former Milwaukee Riverkeeper leader.


"There was so much optimism at the time," Schapiro said. "We had just put a man on the moon."

With the rivers still struggling, is the public getting its money's worth?

"I think they have," said Kevin Shafer, executive director the sewerage district.

"You would not see kayaks in the rivers today, if we did not put that money to clean up the watersheds," he said. "You would not see salmon migrating up the rivers. You would not see the fishermen on the rivers. You would have a much more polluted Lake Michigan."

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