The Chesapeake Bay is a national and local treasure, and an important source of livelihood, recreation and cultural heritage for the region. However, after receiving pollution from the surrounding landscape for many years, the Bay is in trouble. The states in the Chesapeake Bay watershed (Delaware, Maryland, New York, Pennsylvania, Virginia, and West Virginia), the District of Columbia, and the U.S. Environmental Protection Agency are working together to clean up the Bay. They have determined that the key to restoring the Bay’s health is reducing the flow of nutrients (nitrogen and phosphorus) and sediment flowing from each of the Bay States into the Bay. To accomplish this, they have set maximum amounts for nitrogen, phosphorus and sediment in each State’s waters.  All of the states have developed Tributary Strategies that seek to reduce nutrient and sediment pollution while minimizing economic and social burdens on our communities.

Stream Cleaner’s landscape is typical of many watersheds in the rural uplands of the Chesapeake Bay watershed. It has a small town with residential areas, some fallow lands, and roads, and farmland located in the river's bottomland, with cornfields, pastures, and a barnyard. Towns and farms can produce many kinds of pollution, including both non-point source and point source pollution (see Pollution Primer). To keep things fairly simple, the watershed in Stream Cleaner doesn’t have any point sources of pollution, so we don’t have to worry about sewage treatment plants, industry, or large factory farms. We are also ignoring many of the kinds of pollution that can come from non point sources, such as bacteria, pesticides, and motor oil.

In Stream Cleaner, the stream is polluted with the same pollutants that are of greatest concern to the Chesapeake Bay -- excess nutrients (fertilizer) and sediment (dirt).  In the activity; these pollutants are combined into a general "pollution" category.   The user has access to a "tool kit" with five ways - called Best Management Practices (or BMPs) - to reduce pollution: grass buffers, forested buffers, sediment ponds, nutrient management plans, and cover crops. Some of the tools work for urban problems, some for farm problems, and some for both. Each tool has a cost associated with installation, and is able to reduce "pollution" by a certain amount. In reality, different BMPs work differently with different kinds of pollution, but we simplified Stream Cleaner rather than trying to account for nitrogen, phosphorus, and sediment separately.  The following table compares Stream Cleaner's pollution reduction assumptions with those used by the Chesapeake Bay Program.

Activity Notes:

1.      It was necessary to simplify concepts to make this activity playable without a large amount of explanation. This creates a few technical problems. One of these is to have a credible basis for assigning relative amount of pollution from the various landscape sources. Stream Cleaner’s landscape is simple, and one simplifying decision was to combine fertilizer and dirt into a generic "pollution" category. This was done by taking the percentages for Nitrogen, Phosphorus, and Sediment used in the Chesapeake Bay Model for the land uses in the Stream Fixer activity and rolling them into a cumulative "pollution" category for all three parameters. Hopefully, this reasonably corrects for the fact that each different landscape element (corn field, pasture, town, barn yard) has different potentials to deliver different kinds of pollutants. To ground this in our regional reality, this was done using the 2002 modeled data from the Chesapeake Bay Program for the North Branch, the South Branch, and the Cacapon watersheds of West Virginia. The amount of land in row crop for these three segments was increased from 1% to 4% and pasture/hay decreased from 22% to 19%; this was done to emphasize the potential for pollution from row crops.

2.      Using data developed by the Chesapeake Bay Program’s Water Quality Model will give some people real heartburn.   The CBP Model takes information from many small studies, and extends it to apply to the whole Chesapeake Bay Watershed, and to smaller areas such as the Potomac Highlands. While some consider the information generated by this program as the best tool currently available for understanding some very complex problems, others see it as fatally flawed.  Nobody thinks it is absolutely "right," but many think it is the best tool we have at present.  

   • One of the sources of contention about The Model concerns how much total pollution there is, and how much comes from different parts of our landscape.  Long-term water-quality studies are being conducted throughout the Chesapeake Bay Watershed to see how closely the Model simulates reality.  

   • Another issue concerns how much pollution is actually reduced by using different Best Management Practices. The best evidence right now is that the CBP Model actually overestimates how well these BMPs work.  In Stream Cleaner, that could mean that you didn’t clean up the stream as well as the game said you did. In the real world, it could mean that, after spending millions or even billions of dollars to clean up our streams and the Bay, the job may not be done.

Have you ever seen a river full of long green algae? Or looked back as you walked across a stream to see mud swirling up from the bottom where you stepped? Or fallen into the water because the river rocks are covered with "slime." In West Virginia, these are often signs of a stream that might need fixing.

The way we live, and the way we use the land, can cause these kinds of problems. While natural resources, such as forests and other vegetation, provide a balanced amount of nutrients necessary to our streams, an overabundance of nutrients are due to human impact. For example, the fertilizers (like nitrogen and phosphorus) that we use to help plants grow can do damage when they end up in our streams. Long green algae and slimy rocks are good signs that we may be using too much fertilizer.

In the same way, an overabundance of sand and dirt in the stream could be coming from natural sources, but more likely comes from excess erosion caused by the way people manage their land. For example, a large amount of dirt can quickly wash off a construction site where vegetation covering the ground has been removed and erosion control systems have not been installed.

It would be hard to imagine calling dirt pollution when it is in a field, or calling fertilizer pollution when it is used to help plants grow. They only become pollution when they end up in places where they don’t belong. 

A stream doesn’t have to be unhealthy just because people live and work nearby. There are many "tools" that people can use to allow healthy streams and people to live side-by-side.

Here’s your chance to clean-up a stream. Like any fix-it project, you’ll need some tools to get the job done. Just as you can build a wall with a hammer, a few boards and some nails, these cleaning tools will allow you to build barriers between the pollution that we produce (we all do it) and our stream. In other words, our tools will be used to keep precipitation (rainfall and snowmelt) from washing dirt, fertilizer, and other pollution into the stream.

What do we mean by tools? Another term for the kind of tools we will use is Best Management Practices (BMP). They fall into three categories – tools that hold dirt and fertilizer in place, tools that act as a barrier to stop dirt and fertilizer from washing into a stream, and tools that reduce the amount of fertilizer we use in the first place.

Here is a typical West Virginia watershed.  From the pie chart, you can see that forested hillsides cover 70 percent of the landscape, with farms accounting for a little less than 20 percent of the land, and with a small headwaters town and nearby fallow lands covering about 8 percent of the land area.

Nutrients, such as phosphorus and nitrogen, occur naturally in soil, water and the atmosphere. They are required for the growth of plants and for aquatic life. We don’t consider nutrients and dirt from the forested area to be pollution because the forest is a natural source. Excess fertilizer and dirt (from now on, we’ll just call that pollution) comes from the town and farm areas. In the town, this pollution comes from bare ground and over-fertilized lawns. Also, water that hits surfaces like roads and rooftops can’t soak into the ground and actually gains speed as it runs across the ground – which causes erosion. On the farm, the sources are the barnyard, the cornfield and the pasture. The pie chart shows how much pollution is coming from each of these sources. Take a close look, and you might notice that the largest land areas do not necessarily contribute the most pollution.

Now you know about the landscape, the problem, the tools you can use to fix the problem, and the sources of pollution. The only thing you don’t know is that some tools cost more to use than others and they reduce pollution by different amounts. The numbers you now see beside each tool in the toolkit tell you, for example, that a forested buffer costs $1000 for every field and removes 60 percent of the pollution that moves through it. To keep things fairly simple, Stream Cleaner assumes that each of the fields in our landscape has the same footage of land bordering the stream.

You have a total of $10,000 to spend. To use a tool, just drag and drop it over the area where you want to use it. If you try to use a tool in a place where it doesn’t make sense, the computer will ask you "Do you really want to do that?" If you try to use a tool in a place where you have already used it, the computer will tell you "You have already done that." After you place a BMP in a field or in town, you will see a change in your bank account gage (when its on empty, you’re out of money and done), and also a change in the pollution level gage. Your goal is to get the pollution level as low as you can before you run out of money.

Your challenge will be to balance how well the different tools work, how much its costs to install the tools, and how big the different sources are -- with how much money you have to spend. Ready?