Water quality “Like swift water, an active mind never stagnates.” 8 — Author unknown efining water quality depends on its Sediments intended use. A particular body of water Sediments are small soil particles carried by D might be clean enough for farm irriga- surface runoff from logging, forestry, construc- tion and yet too polluted for drinking water. tion, mining, or agricultural sites. Sediments can Water could be clean enough for drinking water, carry nutrients and pesticides that degrade water and yet still be too warm for some aquatic organ- quality. Sediments may settle to the bottom of isms to live in it. streams, smothering aquatic life and fish spawn- Natural conditions sometimes make water ing areas. unsuitable for use. High levels of some inerals and salts are common in some areas, making water unfit for drinking. In other places the Toxics natural quality of the water has been degraded. Toxics can include pesticides, heavy metals, We call this water polluted. Guidelines from the petroleum products from leaking underground Environmental Protection Agency (EPA) for storage tanks, solvents, and water runoff from surface waters often refer to a goal of being hazardous waste disposal sites and landfills. The “fishable and swimmable.” While this does not greatest sources of toxics are sewage and indus- provide precise values for various pollutants it trial wastewater. Toxics are also found in runoff does give a general goal. Water must be clean from forests, farms and urban areas. enough to allow aquatic life to live and not be a hazard to public health. Several types of water pollutants are discussed below. Nutrients Nutrients, such as nitrogen and phosphorus, increase the growth of aquatic plants. When the Bacteria plants die and decay they may make the water Bacteria can come from improperly or incom- pletely treated sewage, failing septic systems, and livestock manure. High levels of bacteria Vocabulary indicate the presence of micro-organisms that can bacteria toxics cause disease. Tests are often done to determine beneficial uses nutrients the concentrations of fecal coliform bacteria. Clean Water Act dissolved oxygen Fecal coliform counts are used as an indicator of coliform non-point source water quality. eutrophication pollution groundwater point source pollution surface water pollution sediments Oregon Department of Fish & Wildlife Water quality • 235 unsuitable for other uses. Excess nutrients may beneficial uses, point sources of pollution— be washed into streams and lakes from sewage those that come from an identifiable source such and septic systems, livestock and pet wastes, and as a pipe—are controlled first. These sources of fertilizers. pollution are the easiest and generally least expensive to find and control. If controlling point Heat sources is not enough to achieve water quality standards, then non-point sources of pollution, Water temperature is critical to many kinds of those that come from wide areas, such as soil aquatic life. Water temperature can be increased eroded from uplands, are included in efforts to when warmer water, from industrial processes or clean up the water. (See Table 2.) irrigation returns, is added to streams. But the Section 303(d) of the Clean Water Act most important factor in raising water tempera- requires that bodies of water that cannot achieve tures in Oregon streams and rivers is a lack of the standards by controlling point source pollu- shade. Without a canopy of vegetation, solar tion alone are placed on a special list—the radiation heats water in streams. Shade does not 303(d) list—and additional measures must be cool water. It helps prevent it from heating. taken to help them achieve the standards. Al- though the Clean Water Act is a federal law, Dissolved oxygen individual states have responsibility for deter- It is not dissolved oxygen, but the lack of it that mining which bodies of water should be on the results from pollution. Dissolved oxygen is 303(d) list. In Oregon, the Department of Envi- essential for the survival of fish and aquatic life. ronmental Quality (DEQ) is responsible for this The decay process—for organic materials list. It is compiled using the best scientific and washed into streams or the increased plant technical information available. In the past growth that goes along with the addition of extra several years many more lakes and segments of nutrients—uses oxygen, making it unavailable streams and rivers have been added to the list. for fish or other aquatic life. Recent additions do not mean that water quality in Oregon is getting worse, but instead reflects more information and knowledge about waters in Clean Water Act the state. Currently there are 1,067 streams and The Clean Water Act includes federal water rivers, 32 lakes and 1,168 stream segments on the quality standards. The standards vary from list. stream to stream and are based on research data. These standards are set according to the natural, or background, conditions for each body of Groundwater water. A stream fed by hot springs is not ex- When we think of water pollution we most often pected to have the same temperature as one fed connect it with rivers, streams, lakes, and other solely by melting snow. The standards are also bodies of surface water. Groundwater can also based on the beneficial uses for that particular suffer from pollution. Groundwater is a precious body of water. The list of beneficial uses is resource. Each day in Oregon 700 million gallons defined by law and includes things as drinking of groundwater are used. The drinking water water, recreation, preserving healthy conditions supply for almost 77% of Oregonians comes, at for aquatic life, fisheries, aesthetics, and irriga- least partially, from groundwater. Groundwater tion. When there are competing beneficial uses in supplies some or all of the drinking water to a river or stream, the Department of Environmen- 3,100 public water systems. tal Quality (DEQ) is required to protect the Groundwater is easily contaminated by beneficial uses that are most sensitive. pollutants. Pollutants dissolved in water can When a particular body of water is identified percolate through the soil and become part of as below the water quality standards for its 236 • The Stream Scene: Watersheds, Wildlife and People Oregon Department of Fish & Wildlife groundwater. Groundwater contamination is is hidden in many everyday activities. Non-point often caused by leaking landfills, failing septic source pollutants come from farm fields, pas- systems, runoff from animal feed yards, leaking tures, backyards, parks, streets, roads, mines, and underground storage tanks, and the improper use construction sites. Anything on the surface of the of fertilizers and pesticides. Nitrates are the most land can be carried with surface runoff to gutters, common form of groundwater pollution. Nitrates storm drains, or ditches and then on to streams come from fertilizers and human and animal and rivers. Some common sources of non-point wastes. Drinking water contaminated with high source pollutants include: levels of nitrates can be harmful to humans and • household chemicals and soaps from livestock. Contaminated groundwater is very driveways, roofs, and yards; difficult, sometimes impossible, to clean up. As • fertilizers and pesticides from farm fields, of March 1993, DEQ had identified 1,359 yards, parks, golf courses, and landscaped groundwater contamination sites in Oregon. areas; • oil, anti-freeze, and other toxic materials Sources of pollutants from streets and roads; Generally we associate water pollution with • eroded soil from farm fields, logging pollutants that come from a pipe, such as dis- areas, and construction sites; charges from factories and sewage treatment • failing septic tanks; and plants. Point source pollutants include heavy • manure from livestock and pets. metals, toxic chemicals, heated water, sewage, radioactive materials and other pollutants from industrial or municipal sources. Often, point Controlling water pollution source pollutants are the most dangerous. But they are not the only pollutants. It is easier and cheaper to prevent pollution than In terms of the volume of pollutants the it is to clean it up. It is illegal to discharge largest source is non-point source pollution in the pollutants into Oregon waters without a permit form of surface water runoff. Rainwater and from DEQ. Some pollution, such as treated melting snow pick up and carry soil, garbage, effluent from sewage treatment plants, is allowed and various toxics as they wash over streets, when a stream is able to process it without roofs, lawns, constructions sites, logging sites, degrading its quality. DEQ has responsibility for and farm fields. It is estimated that non-point seeing that pollution problems are addressed. sources are responsible for half or more of all This agency works with other agencies to ensure nitrogen, coliform bacteria, iron, phosphorus, oil, that the job of controlling pollution, both point zinc, lead, chromium, and copper that enter the and non-point, progresses. Agencies responsible surface waters of the United States. Sediments for forestry, urban areas, and agriculture all play from non-point sources alone are responsible for a part in controlling pollution. Individual cities an estimated $6 billion in damage per year. Even are responsible for overseeing their municipal though many non-point source pollutants are less wastes. toxic than some industrial wastes, they still The Oregon Department of Forestry is damage fish and wildlife and their habitats, responsible for designing and enforcing measures degrade drinking water supplies, promote in the Oregon Forest Practices Act to prevent and eutrophication, and damage the aesthetics and the control non-point source pollution from forest recreation potential of Oregon’s waters. lands. Responsibility for non-point source Non-point source pollution carried with pollution from rural and agricultural lands rests surface water runoff is hard to detect and control with the Oregon Department of Agriculture. because it does not come from a single source.