eral standards reduced the temperature of returned
water, although it generally did not return it to the
original level. During the 1980’s, several states devel-
oped water quality standards for point pollution to
supplement the federal rules, and there continued
to be improvements in stream quality, although at a
slower rate than during the previous decade.
Nonpoint Pollution In spite of continuing gains in
dealing with point pollution during the decade, a
major source of water pollution remained more dif-
ficult to handle. Runoff from farms, parking lots,
construction sites, or industrial sites is not concen-
trated in any one location and is more difficult to
monitor than is point pollution. Nonetheless, such
nonpoint pollution was a major contributor to the
pollution of streams and lakes before, during, and
after the 1980’s. Fertilizers such as nitrogen, used to
enhance agricultural production, are a major source
of nutrient material that becomes available to organ-
isms in water when some of the fertilizer runs off
from agricultural land. The growth of these oxygen-
requiring microorganisms in water reduces the
amount of oxygen available to satisfy the biochemi-
cal oxygen demand (BOD) of fish or useful aquatic
life, leading to fish kills.
Agriculture became an increasingly important
source of this form of pollution during the decade.
For example, approximately 16 percent of all nitro-
gen fertilizer applied in the Mississippi River basin
was washed into the Mississippi. Some advocates
urged the Environmental Protection Agency (EPA)
to act to regulate nonpoint pollution, but the Rea-
gan administration was disinclined to regulate the
environment further.
Nonpoint pollution could be chemical as well as
biological in nature. Runoff from roads or parking
lots added minute amounts of chemicals or heavy
metals of various sorts to nearby water sources. In
this case, the remedy often caused additional prob-
lems. Many cities piped storm water into the sewer
system. Large rainstorms at times caused sewer sys-
tems to bypass water treatment plants because of the
excess capacity. Although road runoff was containedThe Eighties in America Water pollution 1031
A polluted lakefront beach in Hammond, Indiana, poses a health hazard to swimmers.(Library of Congress)