Freshwater: Sustaining Use by Protecting Ecosystems

• Author: Robert W. Adler
• Pages: 205-220

Chapter 14

Freshwater: Sustaining Use by Protecting

Ecosystems

Robert W. Adler

In 2002, the United Nations Committee on Economic, Social, and

Cultural Rights determined that access to water is a fundamental hu-

man right.1Yetbillions of people around the world lack access to clean

water and sanitation, and millions of people each year die of water-

borne diseases.2Over a billion people lack access to an improved wa-

ter supply within one kilometer of their homes, and over two-and-one-

half billion people have no access to modern sanitation.3Virtually

the entire population of the United States, by contrast, has access to

relatively safe drinking water and modern sanitation.4Nevertheless,

freshwater resources and aquatic ecosystems in the United States face

serious threats.5Global warming now poses new threats to those re-

sources and ecosystems.

This chapter addresses freshwater resources and ecosystems that

depend on freshwater flows, such as rivers, streams, lakes, and inland

wetands, as opposed to saltwater resources and ecosystems in the

ocean, estuaries, and coastal waters. (Those resources are discussed in

Chapter 15.) Freshwater also includes groundwater, water stored in

underground aquifers but usually connected hydrologically to surface

water systems. The chapter summarizes the state of U.S. freshwater

resources and ecosystems. It then evaluates changes in U.S. water law

and policy since 2002, and presents policy recommendations to ad-

dress the threats to the nation’s water.

Assessment of U.S. Freshwater Resources and Ecosystems

Surface Water Quality

It is difficult to identify long-term trends in U.S. water quality based

on the limited available data. Waterquality standards, as well as meth-

ods and frequency of monitoring, have evolved and vary from state to

state. Water quality and environmental conditions change with cli-

mate and other factors that are not directly related to land use or hu-

man sources of pollution. Because monitoring and assessment re-

205

sources are inadequate, little or no information is available for many

water bodies, or for all of the characteristics necessary to assess water

quality fully.6

Notwithstanding these limitations, the data are sufficiently clear to

show that U.S. rivers, lakes, wetlands, and other water bodies remain

seriously degraded due to chemical pollution, physical alterations to

aquatic ecosystems, habitat loss and degradation, invasive species,

and other factors. The EPArequires states to identify all water bodies

that are impaired for one or more reasons.7According to EPA,in 2004,

states reported a total of 38,886 impaired water bodies throughout the

country, and a total of 64,581 causes of impairment.8Leading sources

of impairment were pathogens, mercury, sediment, other metals, nu-

trients, oxygen depletion, pH levels, temperature, habitat alteration,

polychlorinated biphenyls (PCBs), turbidity,pesticides, and salinity.9

The U.S. Geological Survey (USGS) conducts a monitoring and as-

sessment program to provide baseline information on water pollutants

such as pesticides, nutrients, volatile organic compounds (VOCs), and

radon, as well as indicators of aquatic ecosystem health. These data

cannot yet be used to evaluate more recent water quality trends be-

cause the decadal timeframes for the studies (1991-2001 and 2002-

2012) have not elapsed. Still, the program does provide useful infor-

mation to judge the quality of a scientifically selected sample of water

bodies with a more consistent record than is possible using disparate

sets of data from all 50 states.10

In the 51 study units assessed, USGS found that most water bodies

were suitable for most common uses (such as swimming and other

recreation, public drinking water supply, and support of fish and

aquatic life), but also widely contaminated—especially in agricultural

and urban areas—by nutrients, pesticides, VOCs and their breakdown

products, and other chemicals. Waterquality varied with land use and

management, as well as natural variables such as geology, hydrology,

soils, and climate.11 Streams and groundwater in agricultural and ur-

ban regions almost always contained mixtures of contaminants (in-

cluding pesticides, organic chemicals, and nutrients), often with sea-

sonally high concentrations.12 USGS found toxics such as mercury,

pesticides, and PCBs in virtually all fish samples from urban streams,

frequently at levels exceeding guidelines for the protection of human

health and wildlife; and organochlorine compounds in sediments

206 AGENDA FOR A SUSTAINABLE AMERICA