Nonpoint source pollution

AuthorJeffrey G. Miller/Ann Powers/Nancy Long Elder/Karl S. Coplan
Although the Clean Water Act (CWA) has now been in eect for more
than 40 years, America’s waters are a long way from being clean. We have
made tremendous progress in controlling industrial a nd municipal dis-
charges, but at the 30 year mark data indicated that more than 40% of our
waters still did not meet the “shable and s wimmable” goals of the Act,
much less zero discharge. e states identied almost 300,000 miles of rivers
and stream s and more than 5 million acres of lakes that did not meet state
water quality goals, and the U.S. Environmental Protection A gency (EPA)
reported that an overwhelming majority of Americans live within 10 miles of
a polluted lake, river, stream, or coastal area. U.S. EPA, L A
(2001), EPA-840-B-00-001. In 2013 EPA reported that 55% of the Nation’s
waters were in poor condition. N R   S A
2008-2009 (2013), EPA/841/D-13/001. Current information may be found
at EPA, National Summary of State Information, at https://ofmpub.epa.
gov/waters10/attains_index.control#total_assessed_waters. Most eorts over
time have focused on reducing the discharges from point sources, primarily
our factories and sewage treatment pla nts, but the bulk of contamination is
now due to more diuse and dicult to control nonpoint sources (NPS). For
example, it is estimated that as much as 90% of the nitrogen and 75% of the
phosphorus reaching the nation’s waters originates from NPS, and g ures
for other pollutants are also high. Especially troublesome are the enormous
amounts of sediments that nd their way into our streams, rivers, and lakes.
In 1991, Congress appropriated funds for the U.S. Geological Survey (Geo-
logical Survey) to begin a national water quality assessment (NAWQA) pro-
gram to evaluate trends in water quality and to understand the relationship
between human activities and water quality. e program, which examined
water quality in more than 50 major river basins and aquifer systems, issued
its rst report in 1999, focusing on nutrients and pesticides. U.S. G
S, T Q  O N’ W, N,  P-
, C N. 1225 (1999). e ndings indicated that in areas where
there is signicant agricultural or urban development, the streams and ground-
water almost always contain complex mixtures of nutrients and pesticides. Id.
958 Water Pollution Control, 2d Edition
At least one pesticide was found in almost every water and sh sample collected
from streams and in more than one-half of shallow wells sampled in agricultural
and urban areas. Id. at 6. While pollutant levels were generally below federal
drinking water standards, those standards do not usually take into account the
accumulative or synergistic impact of multiple chemicals, nor are they always
based on a thorough analysis of the full range of potential health impacts.
Further, the impact on aquatic organisms is not a factor in establishing the
standards, and aquatic organisms may be more aected by these contaminants
than humans. Findings from the rst decade of the NAWQA program (1991-
2001) produced some of the most comprehensive water quality data to date.
Nevertheless, because water quality varies signicantly from season to season
and from year to year, properly tracking uctuations in water quality requires
further long-term monitoring. U.S. G S, W Q
  N’ S  A—O  S F-
, 1999-2001, C N. 1265, at 16 (2004). Fortunately, NAWQA’s
second cycle of studies (2002-2012) built upon initial assessments and provide
additional data for many of its previous study sites.
While we might suppose that streams in agricultural areas would likely
have the highest concentrations of pesticides, the ndings showed that insec-
ticides were present more frequently and in hig her concentrations in urban
than in agricultural streams. U.S. G S, T Q  
O N’ W, N,   P
at 10. Although lev-
els of contamination in aquifers were somewhat lower tha n in the streams
that were sampled, there is still cause for concern there. Groundwater is the
source of drinking water for more t han one-half of the nation, and once
polluted is extremely dicult, if not impossible, to clean up. Additionally,
groundwater and surface water are connected, thus polluted groundwater
can carr y contamination to the surface waters to which it discharges.
Diuse runo may occur in urba n and suburban a reas, or be related to
activities such as farming, forestry, a nd mining. It often carries substantial
amounts of sediment and other pollutant loads. For example, EPA’s national
urban runo progra m showed that stormwater runo from city streets con-
tained toxins and heav y metals at surprising ly high concentrations. U.S.
EPA, R   N U R P  (1983). is
was especially tr ue during the rst few minutes of a rainstorm, referred to as
the “rst ush.” ese contaminants —including oil, gas, a nd other residues
from automobiles a nd truck s, emissions from home and industrial heating
plants, chemical spills, even animal feces —come from all of the activities in
which we engage. e toxic nature of NPS discharges led one environmental
Nonpoint Source Pollution 959
group to characterize it a s “poison runo.” P T  ., N-
 R  D C, P R (1989).
Other studies have emphasized the devastating impact of NPS pollution
on our nation’s coastal waters, and in turn on the health of our oceans. In a
report issued in 2003, the PEW Ocea ns Commission concluded that nitro-
gen runo is “[t]he greatest pollution threat to coa stal marine life today.
PEW O  C’, A R   N : R
  N O P 2 (2003). Oil runo is another substantial source
of coastal waters a nd ocean degradation. e National Academy of Sciences
estimated that the oil runo ultimately ending up in our oceans is equiva-
lent to an Exxon Valdez oil spill (nearly 11 million gallons of oil) every eight
months. Id. at 4. In September 20 04, the U.S. Commission on Ocea n Pol-
icy released its own ocean policy report which, in part, served to reinforce
the nding that NPS is one of the most signicant contributory factors to
our oceans’ degraded health. U.S. C’  O  P, A O
B   21 C (2004). Unfortunately, the situation has
not changed.
In spite of t he severity of contamination from diuse sources, the CWA
does not adequately address this issue nor do many of our other pollution
control laws.
is diuse nature of NPS pollution leads to substantial problems in try-
ing to impose regulatory controls. Simply identifying the locus of N PS pol-
lution and quantifying its amount can be a challenge and is complicated by
the fact that some polluting runo occurs naturally. Additionally, the relative
percentage of natura l (as opposed to man-made) runo can vary accord-
ing to season a nd weather condition, further compounding the problem. In
addition to the practica l problems, political opposition to NPS controls can
also be a severe stumbling block to eective regulation. NPS controls often
involve restrictions on the use of land or methods of operation, and the polit-
ical will to implement such measures may be lack ing.
Section 502(14) of the C WA denes the term “point source” in some
detail, and only point sources are subject to t he national pollutant discharge
elimination system (NPDES) permit program. For the many sources of pol-
lution that fall outside the statutory denition we typically use the rather
awkward “nonpoint source.”

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