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Water Issues - Water Suitability

sources quality percent waters

The U.S. economy depends on water and studies have repeatedly shown a positive relationship between strong environmental standards and economic growth. Good water quality is important to local and national economic development.

Water is a powerful attraction for people. The EPA's Liquid Assets 2000: America's Water Resources at a Turning Point (May 2000) estimates that the travel, tourism, and recreation industries support jobs for more than 6.8 million people and generate annual sales in excess of $450 billion. The Center for Marine Conservation reports that federal, state, and local governments maintain more than 25,000 recreational facilities along U.S. coasts, while private organizations operate another 20,000. One-third of Americans visit a coast each year, spending about $44 billion. According to the U.S. Fish and Wildlife's 2001 National Survey of Fishing, Hunting, and Wildlife-Associated Recreation, these activities produced revenues of $108 billion that year.

More than 95 percent of U.S. foreign trade passes through U.S. harbors and ports. American farmers depend on water to produce and sell billions of dollars worth of food and fiber annually. Each year the Great Lakes, the Gulf of Mexico, and many other coastal areas produce billions of pounds of fish and shellfish. The National Marine Fisheries Service estimated the value of U.S. commercial fishing at about $3.2 billion in 2002. According to the

Summary of quality of assessed surface waters, 2000

Assessed for quality Rated good Rated good, but threatened Rated impaired
Waterbody type Total size Amount % of total Amount % of assessed Amount % of assessed Amount % of assessed
Rivers and streams (miles) 3,692,830 699,946 19% 367,129 53% 59,504 8% 269,258 39%
Lake, reservoirs & ponds (acres) 40,603,893 17,339,080 43% 8,026,988 47% 1,348,903 8% 7,702,370 45%
Estuaries (square miles) 87,369 31,072 36% 13,850 45% 1,023 4% 15,676 51%
Great lakes shoreline (miles) 5,521 5,066 92% 0 0% 1,115 22% 3,951 78%
Ocean shoreline (miles) 58,618 3,221 5% 2,545 79% 225 7% 451 14%
SOURCE: Adapted from "Figure 1. Summary of Quality of Assessed Rivers, Lakes, and Estuaries," in Water Quality Conditions in the United States: A Profile from the 2000 National Water Quality Inventory, U.S. Environmental Protection Agency, Office of Water, Washington, DC, August 2002

USGS, manufacturers use about 9 trillion gallons of fresh water every year.

Water is a fundamental need in every society. Families use water for drinking, cooking, and cleaning. Industry needs it to make chemicals, prepare paper, and clean factories and equipment. Cities use water to fight fires, clean streets, and fill public swimming pools. Farmers water their livestock, clean barns, and irrigate crops. Hydroelectric power stations use water to drive generators, while thermonuclear power stations need it for cooling. Water quality is important to all users, as differing levels of quality are required for different uses. While some industrial users can tolerate water containing high levels of contaminants, drinking water requirements are extremely strict.

Clean Water Act

On June 22, 1969, the Cuyahoga River in Cleveland, Ohio, burst into flames, the result of oil and debris that had accumulated on the river's surface. This episode thrust the problem of water pollution into the public consciousness. Many people became aware—and wary—of the nation's polluted waters and, in 1972, Congress passed the Federal Water Pollution Control Act (PL 92-500) commonly known as the Clean Water Act.

The objective of the Clean Water Act was to "restore and maintain the chemical, physical, and biological integrity of the nation's waters." It called for ending the discharge of all pollutants into the navigable waters of the United States and to achieve "wherever possible, water quality which provides for the protection and propagation of fish, shellfish, and wildlife and provides for recreation in and on the water." The second provision was that waters be restored to "fishable/swimmable" condition.

Section 305(b) of the Clean Water Act requires states to assess the condition of their waters and report the extent to which the waters support the basic goals of the Clean Water Act and state water quality standards. Water quality standards are designed to protect designated uses (such as recreation, protection and propagation of aquatic life, fish consumption, and drinking water supply) by setting criteria (for example, chemical-specific limits on discharges) and preventing any waters that do meet standards from deteriorating from their current condition.

Each state prepares and submits to the EPA a report documenting (1) the water quality of all navigable waters in the state, (2) the extent to which the waters provide for the protection and propagation of marine animals and allow recreation in and on the water, (3) the extent to which pollution has been eliminated or is under control, and (4) the sources and causes of the pollution. The act stipulates that these reports must be submitted to the EPA every two years.

National Water Quality Inventory

Every two years the EPA releases the National Water Quality Inventory, which is prepared from the state assessments. The 2000 report was released in August 2002 and was the latest available in June 2004. The report summarizes information about the quality of the nation's rivers, streams, lakes, ponds, reservoirs, estuaries, wetlands, coastal waters, coral reefs, and groundwater. The EPA reports that wetlands, coastal waters, coral reefs, and groundwater are poorly represented in state monitoring programs because few states have adopted water quality standards for them.


In 2000 the states assessed surface water quality in rivers and streams, lakes (including the Great Lakes), ocean shoreline, and estuaries. Estuaries are areas where ocean and freshwater come together. Due to the tremendous resources required to assess all water bodies in the United States, only a small portion of each water body type is actually assessed for the report.

Table 6.2 summarizes the findings of the report for surface waters. It found that the states had assessed the quality of 19 percent of their river and stream miles, 43 percent of their lake acres (92 percent of Great Lakes shoreline), 36 percent of estuaries, and 5 percent of ocean shoreline.

Water bodies meeting applicable water quality standards for criteria and designated uses were rated "good."

Leading pollutants and sources causing impairment in assessed rivers, lakes, and estuaries, 2000

Rivers and streams Lakes, ponds, and reservoirs Estuaries
Pathogens (bacteria) Nutrients Metals (primarily mercury)
Siltation (sedimentation) Metals (primarily mercury) Pesticides
Habitat alterations Siltation (sedimentation) Oxygen-depleting substances
Agriculture Agriculture Municipal point sources
Hydrologic modifications Hydrologic modifications Urban runoff/storm sewers
Habitat modifications Urban runoff/storm sewers Industrial discharges
*Excluding unknown, natural, and "other" sources.
SOURCE: "Figure 2. Leading Causes and Sources of Impairment in Assessed Rivers, Lakes, and Estuaries," in Water Quality Conditions in the United States: A Profile from the 2000 National Water Quality Inventory, U.S. Environmental Protection Agency, Office of Water, Washington, DC, August 2002

Those water bodies meeting water quality standards, but expected to degrade in the near future were rated "good, but threatened." Water bodies that did not meet water quality standards were rated "impaired."

Only slightly more than half of the assessed rivers and streams were rated good. Slightly less than half of assessed lakes, reservoirs, ponds, and estuaries were rated good. None of the Great Lakes shoreline assessed was found to be in good and unthreatened condition. In fact, 78 percent of the assessed Great Lakes shorelines were rated impaired and the remaining 22 percent were threatened. This is especially significant, because nearly all (92 percent) of the shorelines were assessed. By contrast, only 14 percent of ocean shoreline was rated impaired. However, only a tiny percentage (5 percent) of it was assessed.

Table 6.3 lists the leading pollutants and sources blamed for impairment of assessed rivers, lakes, and estuaries. The primary pollutants are pathogens, siltation, nutrients, metals, pesticides, oxygen-depleting substances, and habitat alterations.

Pathogens are bacteria and viruses that enter water bodies from animal waste, failing septic systems, urban runoff, storm sewers, and combined sewer overflows (CSOs). CSOs are sewer systems in which storm water flows into pipes already carrying raw sewage headed for a sewage treatment facility. During a large rainfall or snowmelt the system's capacity may be overwhelmed, causing the mixture of untreated sewage and storm water to bypass the sewage treatment facility and flow directly into receiving waters. (See Figure 6.8.) In 1994 the EPA ordered communities with CSOs to take "immediate and FIGURE 6.8
Urban runoff flows in different types of sewer systems
long-term actions" to address CSO problems. However, according to a U.S. General Accounting Office (GAO) report presented to Congress in June 2001, CSOs are still used in approximately 900 cities in the United States.

Pathogens in water used for recreational purposes can pose human health risks due to incidental swallowing and skin contact. In addition, pathogens can accumulate in shellfish, prompting officials to issue warnings against eating shellfish taken from certain waters.

Siltation was another leading cause of surface water impairment in 2000. Siltation is the addition of sediment to water bodies. The sediment can be carried by wind or by runoff from construction sites and other nonvegetated lands, eroding banks, and road sanding operations. Siltation alters aquatic habitats by suffocating fish eggs, causing infection and disease among fish, scouring submerged aquatic vegetation, preventing sunlight from reaching aquatic plants, and burying habitat areas of FIGURE 6.9
Effects of siltation in rivers and streams
bottom-dwelling species. The loss of those species then impacts fish and other species that feed on them. Silt in the water can also interfere with drinking water treatment processes and recreational use of surface water bodies. (See Figure 6.9.)

Nutrients in water bodies are primarily nitrogen and phosphorus introduced via runoff of fertilizers and animal waste, failing septic systems, CSOs, and atmospheric deposition. Excessive nutrients pollute water bodies by spurring an overgrowth of plants, algae, and toxic and nontoxic blooms of planktonic marine organisms, such as "red tides" and Pfiesteria. This results in oxygen depletion and decomposition of plant matter. Fish suffocate, and unpleasant odor and taste result. (See Figure 6.10.)

Algal growth off the mouth of the Mississippi River has caused a massive area called an hypoxic zone, which is extremely low in oxygen and devoid of aquatic life. The hypoxic zone in the Gulf of Mexico averaged 8,500 square miles during the summer of 2002. It is blamed on excessive inflow of nutrients from fertilizer use in the agricultural areas bordering the Mississippi River. The EPA reports that a similar hypoxic zone in Long Island Sound may have killed millions of shellfish in the summer of 2000.

Metals are introduced to water bodies through industrial discharges, automobile fluid leaks, normal wear of automobile brake linings and tires, wear of metal roofs on buildings, and atmospheric deposits from power plants and waste incinerators. Many metals are toxic to aquatic organisms and pose a potential threat to humans via fish consumption. Mercury in particular can pose a serious health threat.

Effects of excessive nutrients on lake ecosystem

Oxygen-depleting substances are a leading cause of estuary impairment. Estuaries, which are home to many shellfish species and are used as nursery areas for aquaculture enterprises, usually have large cities nearby. Urban sources, including municipal and industrial discharges, urban runoff, and storm sewers are the most prevalent sources of estuary pollution. Other causes of impairment include hydrological modifications (damming rivers and altering the flow of water) and habitat modifications.

The Great Lakes (Lakes Huron, Michigan, Superior, Ontario, and Erie) contain nearly 20 percent of the fresh surface water on Earth. However, they are impaired by a variety of contaminants introduced via storm water runoff, surface water and wastewater discharges, groundwater, and air deposition.

Only 15 states have coastal waters within their jurisdiction. The three leading pollutants blamed for ocean shoreline impairment were pathogens (bacteria), oxygen-depleting substances, and turbidity (high particle content in the water, causing muddy or cloudy appearance). The sources of those contaminants were urban runoff/storm sewers, nonpoint (having no specific point of release) sources, and land disposal.


A goal of the Clean Water Act was to return U.S. waters to a fishable/swimmable condition. Meeting the fishable goal means providing a level of water quality that protects and promotes the population of fish, shellfish, and wildlife. As a result of polluted waters, fish often become contaminated. When humans eat these fish, they can suffer health effects from the toxins. In May 2003 the EPA published Update: National Listing of Fish and Wildlife Advisories. The report noted that 348 new fish advisories were issued in 2002, and 166 were rescinded, bringing the total number of advisories to 2,800. (See Figure 6.11.) This number is up from 2,618 total advisories in effect in 2001.

A total of 94,715 lakes were under advisory in 2002. The total lake area under advisory increased from 28 percent in 2001 to 33 percent in 2002, while the number of river miles under advisory increased from 13.7 percent in 2001 to 15.3 percent in 2002. In addition, 100 percent of the Great Lakes and their connecting waters and 71 percent of U.S. coastal waters of the 48 contiguous states were under advisory in 2002.

The USDA, EPA, and seven other federal agencies released the National Coastal Condition Report in September FIGURE 6.11
Number of fish consumption advisories issued in 2002
2001. The report examined the ecological health of the nation's coasts based on seven indicators:

  • water clarity
  • dissolved oxygen concentrations
  • loss of coastal wetlands
  • eutrophic condition
  • sediment contamination
  • benthic condition
  • accumulation of contaminants in fish tissue

The report concluded that overall the nation's coasts were in fair to poor condition. Indicators receiving the best marks included water clarity and dissolved oxygen. The poorest rated indicators were coastal wetland loss, eutrophic (high level of nutrients) condition, and benthic (regarding the bottom of a body of water) condition.

In May 2003 the EPA reported in its BEACH Watch Program that 2,823 beaches provided information about beach advisories and closings for the 2002 swimming season. Of these beaches, 2,031 were coastal and 792 were on inland waterways. There were 709 beaches with at least 1 advisory or closing during 2002 (25 percent of those reporting). This percentage was down slightly from 2001 when 27 percent reported advisories or closings. The vast majority of the problems (75 percent) were attributed to elevated bacteria levels. Unfortunately, 43 FIGURE 6.12
Examples of point and nonpoint sources of pollution
percent of the pollutant sources could not be identified. Sources that could be identified included storm water runoff (21 percent), wildlife (11 percent), boat discharges (3 percent), and a number of sewage-related causes.


The main reason that a body of water cannot support its designated uses is that it has become polluted. There are a vast number of pollutants that can make water "impaired," but in order to control a specific pollutant, it is necessary to find out where it is coming from. Although there are many ways in which contaminants can enter waterways, sources of pollution are generally categorized as point sources and nonpoint sources.

Figure 6.12 shows examples of point and nonpoint sources of pollution. Point sources are those that disperse pollutants from a specific source or area, such as a sewage drain or an industrial discharge pipe. Pollutants commonly discharged from point sources include bacteria (from wastewater treatment plants and sewer overflow), toxic chemicals, and heavy metals from industrial plants. Point sources are regulated under the National Pollutant Discharge Elimination System (NPDES). Any facility using point sources to discharge to receiving waters must obtain an NPDES permit for them.

Nonpoint sources are those that are spread out over a large area and have no specific outlet or discharge point. These include agricultural and urban runoff, runoff from mining and construction sites, and accidental or deliberate spills. Agricultural runoff is primarily associated with nutrients from fertilizers, pathogens from animal waste operations, and pesticides. Urban runoff can contain a variety of contaminants, including pesticides, fertilizers, chemicals and metals, oil and grease, sediment, salts, and atmospheric deposits. (See Figure 6.13.) The EPA estimates that as much as 65 percent of surface water pollutants come from nonpoint sources. These sources are much more difficult to regulate than point sources and may require a new approach to water protection.

Groundwater Quality

In "The Hidden Freshwater Crisis" (December 9, 2000, Worldwatch Institute researcher Payal Sampat warned, "We're polluting our cheapest and most easily accessible supply of water. Most groundwater is still pristine, but unless we take immediate action, clean groundwater will not be there when we need it."

The EPA's National Water Quality Inventory for 2000 reported that 39 states assessed water quality in aquifers in their states and identified sources of contamination. In general, groundwater quality in the nation is good. The EPA reports that groundwater can support its many different uses but is potentially threatened by a variety of sources. The leading sources were underground storage tanks containing toxic chemicals, septic systems, landfills, spills, fertilizers, large industrial facilities, and hazardous waste sites. (See Figure 6.14.)

The Federal Role in Protecting Groundwater

Parts of several federal laws help to protect groundwater. The 1972 Clean Water Act provides guidance and money to the states to help develop groundwater programs. The Safe Drinking Water Act of 1974 (SDWA; PL 93-523) and the Safe Drinking Water Act Amendments of 1996 (PL 104-182) require communities to test their water to make sure it is safe and help communities finance projects needed to comply with SDWA regulations. The 1976 Resource Conservation and Recovery Act includes many programs designed to clean up hazardous waste, landfills, and underground storage tanks. New storage tanks must be made of strong plastics that will not rust or leak contaminants into the water table.

The Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (PL 96-510) and the Superfund Amendments and Reauthorization Act of 1986 (PL 99-499; PL 99-563; and PL 100-202) require the cleanup of hazardous wastes that can seep into the FIGURE 6.13
Contributions of air and water pollution from certain patterns of development
groundwater. These two laws also require that cities and industry build better-managed and better-constructed garbage dumps and landfills for hazardous materials so that groundwater will not be polluted in the future.

The Federal Insecticide, Fungicide, and Rodenticide Act (61 Stat 163; amended 1988, PL 100-532) regulates dangerous chemicals used on farms. The act requires the EPA to register the pesticides farmers use against insects, rats, mice, and so on. If the EPA thinks the pesticides might be dangerous to the groundwater, it can refuse to register them.


Both political conservatives and environmentalists credit the Clean Water Act with reversing, in a single generation, what had been a decline in the health of the nation's water since the mid-nineteenth century. In the 1990s, however, some politicians proposed legislation to change the Clean Water Act, giving more authority to the states and more weight to economic FIGURE 6.14
Major sources of ground water contamination, 2000
considerations. These politicians and their supporters (coalitions of industry, agriculture, and state and local governments) argue that enough has been accomplished and that now it is time to make the law more flexible. They claim that the huge cost of maintaining clean water risks making the United States noncompetitive in the international market. Government regulations, they think, demand more than is necessary to maintain drinkable water.

The Future of Water Management

In June 2001 the EPA issued a report titled Protecting and Restoring America's Watersheds. A watershed is defined as a "land area that drains to a body of water such as a stream, lake, wetland, or estuary." In other words, a watershed is determined geologically and hydrologically, rather than politically. Figure 6.15 shows a watershed example and the many issues and processes that affect it.

The EPA believes that the nation's water quality problems cannot be solved by further regulating point-source discharges. Instead, the agency advocates a comprehensive approach that crosses jurisdictional boundaries and addresses all of the air, water, land, and social and economic issues that affect a particular watershed. The watershed approach would balance competing needs for drinking water, recreation, navigation and flood control, agriculture and forestry, aquatic ecosystems, hydropower, and other uses. Currently, these uses are managed by a variety of agencies at the federal, state, and local level.

Actually, the idea is not new. It was originally suggested in 1890 by John Wesley Powell, then director of the USGS. He suggested that the West be divided into watershed units that would be governing bodies and coordinate management of the natural resources within their jurisdiction. More than a century later, the idea is receiving serious consideration.

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