STRETCHES of the Blackstone River in central Massachusetts weave through areas of wilderness where the absence of houses and other man-made structures makes it seem like an undisturbed river far from civilization.
But the serene and idyllic setting masks the pollution below the surface and lodged in the sediment along its banks. The 46-mile-long Blackstone, whose headwaters begin in Worcester, Mass., receives effluent from the city's waste-water treatment plants. Oil from cars and other sources of urban runoff seep into the water. The river, which used to be lined with textile mills during the Industrial Revolution, is still contaminated from the dyes used at that time.
``Worcester's the bathtub, and the river's the drain, so as Worcester washes itself in the bathtub everything goes into the river,'' says Russell Cohen, rivers advocate for the Massachusetts Department of Fisheries and Wildlife.
While restoration efforts have improved the Blackstone significantly, it ``never really has a chance to be clean because right in the very beginning of the river is where Worcester is, and the pollution is carried downstream.''
Twenty-four years ago, the Cuyahoga River in Cleveland became the symbol of severely polluted rivers when it caught fire. Over the years, industries and municipalities had openly dumped chemicals, raw sewage, and other wastes into the country's waters. When the Clean Water Act was passed in 1972 the immediate mandate was to remove this visible goo from the water by stopping point-source pollution - pollution that can be traced to a specific source such as a pipe spewing factory waste. Today much of the point-source pollution has been addressed, and many rivers no longer are topped with chemical foam or run red with dyes, though past contamination from dyes still affects even relatively clean waterways such as the Sudbury River just west of Boston. (see story, right)
BUT river advocates say rivers across the United States like the Blackstone in Massachusetts are now threatened with pollution that has become more subtle and insidious.
``The rivers are apparently cleaner, but it's our viewpoint that river ecosystems are declining pretty badly,'' says Kevin Coyle, president of American Rivers, a river-conservation organization in Washington, D.C. Mr. Coyle says much of this degradation is caused by nonpoint-source pollution, which has become the leading source of pollution into the nation's water bodies.
Nonpoint-source pollution is loosely defined as runoff from farms, city streets, and industry. When it rains, fertilizers, chemicals, pesticides, oil from cars, and other wastes are washed into rivers and streams.
The effects are slow but cumulative, Mr. Cohen says. The runoff feeds rivers with too many nutrients, which lead to algal blooms. The blooms use up most of the oxygen, so other organisms can no longer live.
Mr. Coyle says rivers then become devoid of life, even though they may look clean. ``The river ecosystems, ... the sensitive little critters that live in the streambeds are endangered, and until we can figure out how to deal with nonpoint pollution, we're not really going to save the rivers,'' he says.
Just how many rivers in the US are in trouble?
According to Geoffrey Grubbs, director of the Assessment and Watershed Protection Division at the Environmental Protection Agency (EPA), the US has roughly 2 million miles of rivers and streams. But because such a large number is hard to monitor, only one-third is measured for water quality. Of that fraction, about 240,000 river miles are not meeting water-quality standards, which the EPA defines as fishable or swimmable.
The good news, Mr. Grubbs says, is that most of the nation's water is meeting EPA objectives. He comes to this conclusion because many of the 2 million river miles not measured are in Alaska and are likely to be clean. ``The bad news is that 240,000 miles is a lot of water,'' he says, adding that agricultural runoff is the biggest cause of the pollution.
RIVER advocates are looking to the Clean Water Act, which is up for reauthorization this year, to address some of the nonpoint-source pollution problems. Both the House of Representatives and the Senate plan to introduce a bill this fall.
``The debates will be very thorny because to address nonpoint-source pollution you have to deal with land-use issues,'' Coyle says. ``That's a little different from telling a factory it can't dump stuff in the rivers.''
But Grubbs is more optimistic regarding land-use issues, especially for agriculture. ``So much of what farmers do is governed by the contracts that they create with the [US] Department of Agriculture for the kind of crops they grow and the cost-share programs the USDA has to help them with land-management practices,'' he says. Changes in agricultural practices will depend somewhat on the USDA ``and what it does with farmers to help them do the right thing,'' he says. ``There's some very positive stuff going on in that regard.''
Coyle says one way to slow agricultural runoff is to have narrow strips of land along rivers that act as natural filters. A handful of states have already enacted laws requiring new development to be set back from rivers a certain number of feet.
Other issues will also be hotly debated in the Clean Water Act, Coyle says. Those include addressing urban sewage-treatment systems that use only one pipe for sewage and storm-water runoff: After a heavy rain, the overflow gets flushed into the rivers. Environmentalists will also push for measuring a river's water quality by examining biological criteria - determining the health of the wetlands, fishes, and other creatures. Currently, scientists take a chemical analysis of the water to determine how many parts per million of certain chemicals it has. ``One of the things that would help us better understand what we're doing to the natural environment is to employ not just chemical criteria ... but looking at the entire surrounding of the water,'' Coyle says.
``The Clean Water Act reauthorization would be a very important tool,'' Cohen says. ``It would be of great value just as the first incarnation of the Clean Water Act was the primary stimulus of ... dealing with point-source pollution.''