A Water Pollution Solution – A Case Study in Success
There’s probably a stream or river near you that looks unhealthy, right? So what’s making it sick? And how can we transform degraded waterways into healthy streams again?
To help clean up rivers across the nation, this serious science video decodes how the Pleasant Valley Branch of the Pecatonica River went from a sediment-choked, nutrient-polluted waterway to a quality, cold-water trout stream in just a few years. Discover how computer science combined with land use practices and partnerships make the impossible a reality.
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Like many valleys across the country, Pleasant Valley, located in Dane County, Wisconsin, contained a stream that over time became degraded to the point of being classified as “impaired”. According to the EPA, this means that, “the river was considered too polluted or otherwise degraded to meet the water quality standards set by states, territories or authorized tribes in the U.S.”
The Pleasant Valley Branch of the river became filled with sediment from agricultural run-off. That sediment also contained large amounts of phosphorous and nitrogen that caused excessive algae and plant growth in the river. Fish and other aquatic species dwindled and the waters officially were listed by the DNR as impaired. Like many streams in agriculturally dominated landscapes, the outlook for the river appeared grim.
However, a new creative partnership between the U.S. Fish and Wildlife Service, Wisconsin Department of Natural Resources, The Nature Conservancy, the University of Wisconsin-Madison, the Dane County Land Conservation Division and local farmers began to reverse the fate of the Pleasant Valley Branch.
Using a variety of science and technology to develop a case study, the stakeholders formed a systematic plan to reduce the ag-induced sediment and phosphorous load degrading the steam. They spoke to those farmers about new farming methods and nutrient plans that would help the stream while also helping them make more money through conservation and efficiency. These strategies included no-till planting, dual crop rotation, contour farming, nutrient management of fertilizers, and better practices of handling of manure.
Over time, the stream scientists, known as hydrologists, noticed significant changes taking place in the health of the stream’s ecosystem. Combined with physical stream bank restoration using rocks to stabilize sediment, these improvements resulted in something few expected to see in just a few years… return of trout to the stream.
To discover the science and partnership dynamics of this entire story, watch the video here plus:
Explore the extended learning section below by clicking on the “Learn More” tab below
Or better yet, ask your teacher to download the lessons below so your entire classroom can share in peer-driven learning.
Also, find out more about what you can do to keep your local waters healthy and clean by checking out the website of our educational partners, Wisconsin Land+Water and Project WET. Project WET offers a variety of activities (including one here), games and water education resources for teachers.
What are the challenges of turning a damaged “impaired” stream into a healthy ecosystem? At first glance, it may seem like an impossible task. But you might you may be surprised by how many different methods exist to restore streams using science and technology. Of course some work better than others and you need to match the right methods with the stream’s variables to determine how you would go about restoring a stream.
Stream ecologists, those who study stream and river habitat, must first identify a stream that will benefit the most from restoration efforts. This isn’t as easy as just picking the most damaged stream in an area. Some streams, unfortunately, are impaired to the point of almost being beyond repair. A balance must be struck between a stream that needs help and a stream that can still be saved.
Once a damaged stream is selected, the threats to it must be identified. For most streams, run-off from farm fields and/or pollutants from cities cause most of the damage. In rural areas, farmers sometimes plant right up to the banks of streams and create prime conditions for serious erosion to spill sediment and phosphorous into streams. In cities, developers commonly use heavy machinery to physically “channelize” streams. Channelization means making streams flow in straight lines through the use of concrete, bulldozers, or a combination of both. Other common threats to stream quality include invasive species, over-fishing, and off-road vehicles.
With so many threats, how can anyone begin to address or afford solutions? The solution is in forming partnerships. Some stream restoration projects involve many different partners that collectively contribute funding, science, staff and management. Other projects are completed through the hard work of dedicated volunteers. Those involved in a stream restoration project must figure out what resources they have to work with and go from there. Major projects, such as reverting channelized streams back to natural courses with bulldozers and temporary dams, might cost millions of dollars. Putting rocks into an eroding bank to stabilize it on the other hand might be mostly free other than the cost of a truck and lunch for a few volunteers.
Every restoration project is different. Some only focus on a few specific places along a stream. Others use a variety of methods throughout a several-mile stretch of stream. The one thing that all stream restoration projects have in common is creativity. Those who plan these projects must determine what stream restoration methods are best suited to their project site and budget. Then the actual process of restoration begins.
So what are some of the common methods of restoring streams? The first step often involves simply speaking to landowners and industries operating in the watershed about what they can do to limit their impact. The other stream restoration methods in a plan will benefit greatly from these initial conversations. Stream restorers must also make sure that the channel of the stream is not blocked anywhere. Imagine restoring a stretch of stream, only to find out that no fish or creatures swim up or downstream to get to that stretch.
Restoration projects that have larger budgets generally alter channels and remove blockages through the use of heavy equipment. They construct pools, curves in the stream, and remove smaller structures that block fish passage. This focus on channel restoration benefits projects because it also may solve problems like bank erosion and create habitat for aquatic species at the same time. Streams naturally twist and turn which causes the depth to change and debris and sediment to settle in different areas along the riverbed. Restored streams really need to have these features before true restoration can take place.
Stream ecologists plant native trees and plants in almost every stream restoration project. This method, like restoring twists and turns in the stream, solves multiple problems at once. Native vegetation provides food and habitat for species on the land along a stream. Insects that live on this vegetation fall into the water, as do leaves and branches. Animals in the stream, in turn benefit at the same time. Plants and trees also help hold the stream banks in place, preventing erosion and sedimentation.
Now take a moment to consider… “Have you figured out the common theme so far?” Every stream restoration project looks for ways to fix many problems with the fewest number of solutions. But the methods mentioned above pale in comparison to the best method of stream restoration: dam removal.
No matter where it’s happening, the topic of dam removal is usually controversial. Dams were put in place to generate electricity, prevent flooding, store drinking water, and create recreational opportunities. So it turns out that a lot of people depend on dams in some way. At the same time, dams have significant negative impacts on wildlife and the natural ecosystems of rivers. They flood habitat, prevent most fish from moving upstream, and change the water temperature both upstream and downstream. This also impacts oxygen and bacterial content in the water that further compounds the impact on natural ecosystems. Increasingly, people are pushing for the dams that no longer benefit communities to be removed and the rivers restored.
The largest dam removal in recent history took place on the Olympic Peninsula of Washington. The Elwha Dam, on the river of the same name, was removed in 2011 and the Glines Canyon Dam further upstream was removed in 2014. The 45 mile-long river now flows freely and salmon now spawn in its upper reaches. The Boardman River in northern Michigan and the Klamath River in northern California will also see major dam removals in the next few years. Each dam removal gives stream ecologists a chance to monitor how streams and the species inhabiting them respond. So far, the results are promising.
Stream restoration, whether it happens on a small stream in southern Wisconsin or a river in northwest Michigan, or on a large river in the wild Northwest U.S., provides an opportunity to not only help the planet, but offers all kinds of insight and learning opportunities about ecosystem restoration. There are likely some stream restoration projects happening near you. So do a little online investigation to see what they are, and what role you can play in making the planet a little healthier for all of us.
• An extra 275 pounds of phosphorus over-fertilizing a river can potentially produce 137,500 pounds of algae downstream.
• Phosphorus is an essential element for plant life, but too much can speed up eutrophication causing a reduction in dissolved oxygen that other lifeforms require.
• Besides phosphorous, nitrogen contributes to nutrient pollution in surface and ground water. Infants are vulnerable to a nitrogen-based compound called nitrates in drinking water.
Like many valleys across the country, Pleasant Valley, located in Dane County, Wisconsin, contained a stream that over time became degraded to the point of being classified as “impaired”. According to the EPA, this means that, “the river was considered too polluted or otherwise degraded to meet the water quality standards set by states, territories or authorized tribes in the U.S.”
Using a variety of science and technology to develop a case study, the stakeholders formed a systematic plan to reduce the ag-induced sediment and phosphorous load degrading the steam. They spoke to those farmers about new farming methods and nutrient plans that would help the stream while also helping them make more money through conservation and efficiency. These strategies included no-till planting, dual crop rotation, contour farming, nutrient management of fertilizers, and better practices of handling of manure.
To discover the science and partnership dynamics of this entire story, watch the video here plus:
Healthy Natural Environments - from Project WET
