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Keeping Pace with Science and Engineering. 1993.
Pp. 8-38. Washington, DC: National Academy Press.
Nutrient Loadings to Surface Waters:
Chesapeake Bay Case Study
Thomas C. Malone, Walter Boynton, Tom Horton,
and Court Stevenson
Nutrient pollution poses the greatest of all recognized threats to
Chesapeake Bay.
L. Eugene Cronin, Baltimore Sun, March 22, 1967
The thing that really bothers me is that when people like me grow
old and die off, there leaves a generation back that has no idea of
what the conditions of the river were. They don't have the memory
at all about the ten barrels of crabs a day a person could catch . . .
about the soft crabs crawlin' in the clear water across grassy bot
toms.... There's going to be nothing in those computer memory
banks . . . that can generate the enthusiasm for the Bay that those
sights and sounds did.
Senator Bernie Fowler, Baltimore Sun, June 14, 1992
Nutrient inputs that result from human activities often cause aquatic
ecosystems to become overloaded with nutrients and deficient in oxygen, a
process referred to as cultural eutrophication. This phenomenon occurs
when nutrient inputs exceed the ability of the system to absorb and use
them its assimilation capacity resulting in the degradation of water qual-
ity.i Since the 1960s, environmental scientists and managers have struggled
with the causes, consequences, and prevention of eutrophication. Our analysis
8
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CHESAPEAKE BAY CASE STUDY
9
is concerned with the relationship between environmental research by the
science community and the formulation, implementation, and evaluation of
nutrient control strategies by the management community.2 We will not
explicitly treat such important problems as water use, the enforcement of
government regulations, or the development of a new social ethic for the
public stewardship of natural resources. We ask the question, "flow and
why does the management community respond (or not respond) to new
scientific information on the causes and consequences of nutrient loadings
to surface waters?"
Since the flow of information between the research and management
communities is neither one way nor linear, we must also be concerned with
the response of the research community to the needs of management. The
interplay among the research and management communities characteristi-
cally involves feedbacks between different levels of government (local, state,
and federal), public and private institutions, citizens' groups, and individu-
als. The complex nature of these interactions and the current compartmen-
talization of ecology and economics into opposing forces create an inertia
that reflects both the bureaucracy within which the research and manage-
ment communities are imbedded and the multiple ecological, economic, and
social interests that management agencies represent.
For this case study, we have selected the Chesapeake Bay. As for most
of the nation's coastal ecosystems, nutrient loading to the watersheds of the
main Bay and its tributaries (Figure 1) has increased substantially in the
decades since World War II, largely as a consequence of rapid population
growth and increases in agricultural fertilization, the density of farm ani-
mals, and atmospheric inputs. This has been a matter of increasing concern
throughout the Chesapeake Bay watershed, especially in the states of Mary-
land and Virginia, the economies of which are closely tied to the Bay and its
resources. Perhaps as a consequence of this and its proximity to Washing-
ton, D.C., the Bay has been the subject of much political and scientific
attention and controversy since the early 1960s. For these reasons, and
because the responsibility for nutrient management resides with individual
states, our analysis of the relationship between science and management
will focus on the state of Maryland. We hope to show how uncertainty, the
availability of cost-effective solutions, and forces inherent to the conduct of
the science and management communities have interacted to (1) limit the
information exchange critical to the objectives of both communities and (2)
inhibit the timely development and implementation of comprehensive nutri-
ent management strategies.
The environmental effects of anthropogenic nutrients enrichment (cul-
tural eutrophication) began to receive national and international attention in
the 1960s with major efforts to control nutrient loadings and continued
during the 1970s to the present. In the Chesapeake region, the main event
_
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0
1 1 -
_:
WV
~__
FIGURE 1 Drainage basin of Chesapeake Bay.
MALONE, BOYNTON, HORTON, AND STEVENSON
NJ |
~ J
call_ DE
Choptank
Nanticoke
during this period was the U.S. Environmental Protection Agency (EPA)
Chesapeake Bay Study mandated by Congress in 1976, implemented in
1977, and completed in 1983 with the release of the Chesapeake Bay Pro-
gram reports: A Profile of Environmental Change (EPA, 1983d), Findings
and Recommendations (EPA, 1983b), and A Framework for Action (EPA,
1983c). The implementation of this study and the publicity that surrounded
its completion had a major impact on the perspectives of both science and
management communities and on the interplay between them, much of which
was (and is) modulated by public interest and political pressure. Thus, for
the purposes of our analysis, we divide our narrative of the sequence of
events into the "formative" years prior to the EPA Bay Study (1965-1977),
.
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CHESAPEAKE BAY CASE STUDY
11
the period of the EPA Bay Study (1977-1983), and the "action" years fol-
lowing the Bay Study (1983-1992) (see Figure 2).
THE FORMATIVE YEARS
Nationally, the perception of eutrophication as a water quality problem
was largely based on studies of the effects of nutrient loading to freshwater
systems in which phosphorus (P) is usually the controlling nutrient (Ameri-
can Society of Limnology and Oceanography, 1972; National Research Council,
1969). Vollenweider (1968, 1976) published his widely accepted model of
phosphorus limitation in lakes, an empirical analysis that also appeared to
be applicable in concept to estuaries where marine and freshwaters mix
(Ketchum, 1969). The generality of Vollenweider's model for lake systems
was vividly demonstrated through the experimental manipulation of lakes in
Canada (Schindler, 1974). Schindler (1977) went on to show that lake
communities are able to compensate for deficiencies of nitrogen (N) and
carbon through gaseous exchange with the atmosphere, and that attempts to
control nitrogen loading may actually degrade water quality because they
may result in the growth of noxious blue-green algae (which are capable of
fixing nitrogen). In contrast, research in marine systems was beginning to
produce evidence that N. not P. is the principal nutrient limiting primary
production (Ryther and Dunstan, 1971). However, despite new scientific
evidence that N-control would also be necessary (see Boynton et al., 1982;
Nixon and Pilson, 1983), nutrient management in the Chesapeake region
through the 1970s and into the 1980s was dominated by the growing body
of evidence for phosphorus limitation in freshwater systems.
Federal Studies and Legislation
The Water Pollution Control Acts (also known as the Clean Water Acts,
CWAs) of 1965 and 1972 reflected a growing concern over the pollution of
lakes and rivers and the threat this posed to the nation's water supply, living
resources, recreational use, and aesthetics (see Figure 2~. The 1965 CWA
required the adoption of enforceable ambient water quality standards for all
interstate waters. As in the past, the primary responsibility for nutrient
management was vested in the states. In the 1972 amendments to the CWA,
Congress drastically altered the nation's management approach. It changed
the focus from ambient water quality to effluent standards by calling for the
nationwide implementation of secondary treatment. Technology-based per-
formance standards became the basis of regulating nutrient (and other con-
taminant) inputs, and federal funding to the states for the construction and
upgrading of sewage treatment plants (STPs) was increased from 55 percent
.
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12
Science and Engineering
- NAS International Symposium on Eutrophication ~
- Point source pollution: the upper Potomac
_ .
- ASLO symposium on nutrients and eutrophication ~
~ To ! ^~ _ ~ A ~ _ L _ 1 _
- ~HeCIS CT I ropical worm signed puolibneu
- Nonpoint source watershed workshop
- EPA Chesapeake Bay study begins
- EPA symposium on effects of nutrient
enrichment in estuaries
- Chesapeake Bay Technical Studies:
A Synthesis
- Chesapeake Bay: A Profile of Environmental
Change
- Chesapeake Bay monitoring program; seasonal
anoxia in the Chesapeake Bay
- CatastroDic 1984 anoxia in the Chesapeake Bay ~ 1985
- STAC: Nutrient Control in Chesapeake Bay ~
- Nitrogen in groundwater - ~
- Sea Grant anoxia workshop
MALONE, BOYNTON, HORTON, AND STEVENSON
Policy and Regulation
1965 ~- Federal Water Pollution Control Act
- Federal Rivers and Harbors Act
- Clean Water Restoration Act
_~ - Estuary Protection Act
- First Govenor's Conference on Chesapeake Bay
- Potomac-Washington Metro Area
Enforcement Conference
1 970 ~
_~
- AL - - Advanced wastewater treatment of phosphorous: upper Potomac
_ ~ - Federal Water Pollution Control Act
_ - · I ' _ - Coastal Zone Management Act
19 75 ~ ~ - Chesapeake Bay Status Report
, ~- Wasteload Allocation Study
· National Estuary Study
- Workshop: Tri-County Council of Southern Maryland
- Bi-state Conference on the Chesapeake Bay
- Chesapeake Bay future conditions report
~ ~ - ~- Chesapeake Bay Commission established
1980 , - Patuxent "Charrette"
, - - Chesapeake Bay Commission: Need to control
,_ both nitrogen and phosphorous
| ~ - BMP cost-sharing program initiated
- ~' `-~-Maryland enacts stormwaterlaw
· - Water Quality Management Plan for the Patuxent
River Basin approved by EPA
- Chesapeake Bay Commission endorses nonpoint
nutrient control plan
- Chesapeake Bay Program Findings and Recommendations:
A Framework for action; Conference on Maryland's Future:
Chesapeake Bay Agreement
_-- - MOUs: EPA, NOM, USGS, SCS, and FWS
it- - Maryland legislation
- - Chesapeake Bay Restoration Plan
, - Maryland: Phosphate detergent plan
- Reduction in federal matching funds for STPs
`-. - Maryland: Chesapeake Bay Trust established
~ _
1990 -
_ L a- - r
, - - Clean Water Act reathorized and amended
- Chesapeake Bay Commission report on nutrints
I-- - 2nd Chesapeake Bay Agreement signed
-- - Chesapeake Bay Program Implementation Committee:
Restoration Progress and the Course Ahead
- Maryland: Deadlines for implementation of nitrogen removal
t- on the Patuxent River
- Coastal Zone Act: Nonpoint-Source Nutrient Control
- Baywide nutrient reduction reevaluation; Chesapeake Bay
Agreement amended
FIGURE 2 Timeline of significant events in the Chesapeake Bay management
program.
-
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CHESAPEAKE BAY CASE STUDY
13
to 75 percent of capital costs. The act also outlawed all point-source dis-
charges of contaminants and established a permit process for dischargers
who could not meet this requirement. This was the National Pollutant
Discharge Elimination System (NPDES), which set legal limits on the quan-
tities of contaminants that could be discharged. The 1972 CWA effectively
gave the federal government the enforcement power to regulate nutrient
inputs to the nation's surface waters. The responsibility for implementation
remained with the states, which were mandated to report on water quality
within their borders beginning in 1975. Stimulated by the availability of
federal funds and guided by the prevailing "wisdom" calling for the control
of point-source P inputs, a nationwide effort was set in motion to upgrade
all STPs to secondary treatment, with advanced wastewater treatment for
removing phosphorus as necessary.
In addition to the CWAs, several studies were initiated by federal legis-
lation during this period. The 1965 Rivers and Harbors Act directed the
U.S. Army Corps of Engineers to conduct a comprehensive "study of water
utilization and control of the Chesapeake Bay Basin," including water qual-
ity control. The 1966 Clean Water Restoration Act directed the Department
of the Interior to conduct a study of estuarine pollution nationwide, and the
1968 Estuary Protection Act directed Interior to "study and develop the
means to protect, conserve, and restore" the nation's estuaries.
This legislation resulted in four important reports, which laid the foun-
dations for and ultimately led to the EPA Bay Study:
1. In 1969 the Water Pollution Control Administration reported on the
adverse effects of nutrient enrichment in the tidal freshwater reaches of the
Potomac and Patuxent rivers.
2. In 1970 the Interior Department's national estuarine study, conducted
by the Fish and Wildlife Service, recommended that "An all-out cleanup
program for the Chesapeake Bay area might serve as a national and even an
international demonstration area, showing what can be accomplished by an
enlightened public and a responsible Congress."
3. In 1973 the Corps of Engineers released its Chesapeake Bay Status
Report in which water quality in the Bay was assessed as good, with local
problems limited to the tidal freshwater reaches of some of the Bay's tribu-
tar~es.
4. In 1977 the Corps presented its Chesapeake Bay: Future Conditions
report (published in 1978) to the bi-state conference on the Bay. The report
acknowledged the potential significance of excess nitrogen and phosphorus
loading, listed (but did not quantify) major nutrient sources, and suggested
that land use and nonpoint sources of nutrients are related.
It is noteworthy that, although the Corps and Interior reports acknowl-
edged the link between land use and nonpoint-source nutrient loadings, the
,,,
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4
MALONE, BOYNTON, HORTON, AND STEVENSON
management community would not give control of nonpoint sources serious
attention until the late 1980s and early l990s. This preoccupation with
point sources is evident in EPA's 1975 report to Congress, which proclaimed
overenrichment from sewage to be a major problem in the nation's estuar-
ies. The Chesapeake Bay was identified as being particularly vulnerable.
Under the leadership of Maryland's Senator Charles McC. Mathias, this
would cause the Congress in 1976 to direct the EPA to "undertake a com-
prehensive study of the Bay's resources and water quality, and to identify
appropriate management strategies to protect this national resource."
The Chesapeake Region
In the midst of these studies and federal legislation, symptoms of
overenrichment were appearing in Chesapeake Bay and its tributaries during
the late 1960s and early 1970s. Massive algal blooms, oxygen depletion,
and fish kills in the upper Potomac River were gaining the attention of the
public and federal government officials in Washington, D.C. Scientists
raised the issue of excess nutrient enrichment in general and N loading in
particular during the first Governor's Conference on the Chesapeake Bay in
1968 (Jaworski, 19901. Nutrient distributions and historical records dating
back to the 1930s indicated a trend toward increasing eutrophication in the
upper reaches of the Bay and its tributaries (Carpenter et al., 1969; Heinle
et al., 1970~. Declines in the abundance of submerged aquatic vegetation
(SAY) were documented in the Rhode River estuary (Southwick and Pine,
1975), the upper Patuxent River estuary, and the main Bay (Bayley et al.,
1968, 19781.- Stevenson and Confer suggested (1978) that these declines
might be related to decreased light because of excessive algal growth. Evi-
dence was also accumulating that wastewater inputs to the upper Patuxent
River were beginning to cause eutrophication in the lower Patuxent (Flemer
et al., 1969~. The 1975 Wasteload Allocation Study, conducted by Hydroscience,
Inc. under contract to the state of Maryland, concluded that P is the primary
nutrient limiting phytoplankton production in the Bay and that the removal
of P from sewage wastes is the highest priority for improving water quality.
At the same time, research on estuarine circulation highlighted the need for
a more systemwide approach to material transport and retention (e.g. Heinle
et al., 1970; Pritchard, 1969~.
The concerns of federal officials, scientists, and some local officials are
clearly documented by the Baltimore Sun. For example, U.S. Congressman
Carlton Sickles from Maryland claimed that the Bay is polluted "to the
point of public danger," and an official of the U.S. Fish and Wildlife Service
reported that the Bay "could be dead in five years" (April 23, 1966~. The
Assistant Secretary of Interior for fish and wildlife concluded that "you
can't clean the Bay up, you've got to clean up the watershed" (August 17,
.
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CHESAPEAKE BAY CASE STUDY
15
1966~. Congressman Rodgers Morton expressed concern that the Bay is
getting worse (February 17, 1967), and the founders of the Chesapeake Bay
Foundation charged that "ecologically, the whole Bay is in danger" (June
19, 1967~. Leading Chesapeake Bay scientists announced that "Nutrient
pollution poses the greatest of all recognized threats to Chesapeake Bay"
(L. Eugene Cronin, March 22, 1967) and that concerns over thermal pollu-
tion from power plants are distracting the science and management commu-
nities from the real problem, sewage pollution (Donald Pritchard, July 1,
1970~. During this period, a study released by the Baltimore Regional
Planning Council concluded that excess N and P inputs from sewage, agri-
culture, and natural sources were among the Bay's most important pollution
problems (November 5, 1968~.
In contrast to the perspective of federal officials and reports by local
scientists and citizens' groups, state officials in Maryland insisted that the
Bay was doing just fine. A representative of the State Board of Natural
Resources referred to claims that the Bay is polluted and a public hazard as
"irresponsible" (April 23, 1966~. The Maryland Department of Chesapeake
Bay Affairs issued a statement that "Bay water quality is good and getting
better" (June 20, 1969), and Governor Marvin Mandel announced that "wa-
ter quality rivals that of 25 years ago" (June 25, 1969~. As late as 1977,
state management officials continued to claim that the Bay was healthy and
that, with the exception of a few hot spots, changes in water quality were
due to natural climatic cycles (February, 1977, Baltimore Sun series, "Chesapeake
Still at Bayer. Thus, the governing body responsible for implementing
nutrient control plans, the state, was the least receptive to scientific evi-
dence indicating the early stages of baywide eutrophication.
Control of Point Source Nutrient Loading
In the late 1960s, Jaworski et al. (1969, 1972) documented long-term
nutrient trends and related changes in the ecology of the upper, fresh reach
of the Potomac. For the first time in the Chesapeake region, Jaworski et al.
clearly demonstrated a relationship between nitrogen and phosphorus load-
ing from municipal wastewater discharges and deteriorating water quality,
and prescribed a program of advanced wastewater treatment to remove N
and P. and lower biological oxygen demand (BOD), a measure of nutrient
loading. In 1969 the Potomac River-Washington Metropolitan Area En-
forcement Conference agreed to set limits on the amounts of P and N that
could be discharged into the upper estuary from STPs as well as on BOD
levels (Jaworski, 1990~. The agreement was achieved in part because the
Washington metropolitan area was faced with a ban on new construction if
no action was taken and in part because President Johnson, upon signing the
1965 CWA, made restoration of the Potomac a national priority. Jaworski's
i_
._
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16
MALONE, BOYNTON, HORTON, AND STEVENSON
research provided the scientific basis for action, but the politics of the day
provided the leverage. By 1972 the Blue Plains STP, which discharges into
the tidal (freshwater) Potomac, had begun construction of an advanced waste-
water treatment facility to remove P and lower BOD. Implementation of N
removal was delayed, in part because the management community was skepti-
cal of the need and in part because there was no cost-effective technology.
As this chapter in the Potomac episode was drawing to an end, a grass
roots confrontation was developing in the Patuxent River watershed. It
involved local politicians and scientists on one hand and regulatory agen-
cies of the state and federal governments on the other (Bunker and Hodge,
1982~. In 1971 a workshop involving university scientists and the Tri-
County Council of Southern Maryland concluded that the water quality of
the lower (salty) Patuxent River estuary had declined to unacceptable levels
as a consequence of increases in municipal wastewater nutrient loadings to
the upper (fresh) Patuxent. Critical to this conclusion was the existence of
"baseline" water quality data collected in the 1930s by university scientists.
Armed with this information and a commitment to restoring the Patuxent,
the Tri-County Council under the leadership of Senator Bernie Fowler ap-
pealed to the state for action over the next five years (1972-1976) to no
avail. Finally, in 1977, the council filed suit against the EPA to halt the
expansion of an upstream STP until an environmental impact statement
could be prepared. In 1978 the council again filed suit, this time against
both the state and EPA, claiming that the Patuxent River Basin Water Qual-
ity Management Plan, which had been approved by EPA, violated 13 of 15
requirements of the 1972 Clean Water Act. The plan advocated P control as
the preferred advanced wastewater treatment method for controlling eutrophi-
cation of the Patuxent. The council felt that N control was also needed, a
position advocated by the Patuxent River Technical Advisory Group (TAG),
an ad hoc committee of prominent university scientists.
The U.S. District Court ruled in favor of the Tri-County Council and
directed EPA to prepare an environmental impact statement and the state
and EPA to prepare a new water quality plan for the basin. As part of this
process, the state contracted with HydroQual, Inc. to assess the impact of a
set of nutrient control scenarios using a computer model. The model pre-
dicted that P removal would be sufficient, a conclusion that the TAG did not
agree with. Following an evaluation of the HydroQual model, the TAG
concluded in a letter to William Eichbaum (assistant secretary for the newly
created Office of Environmental Programs, Maryland Department of Health
and Mental Hygiene, February 6, 1981) that, although the model "is at or
near the state-of-the-art for water quality modeling," uncertainties associ-
ated with the entire modeling process "preclude the use of model projec-
tions as the sole foundation for a management decision of this nature."
At this point the state was in a bind. In the absence of an approved
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CHESAPEAKE BAY CASE STUDY
~7
1
nutrient control plan, the federal government was threatening to withdraw
funding to build and upgrade STPs on the river. Faced with the loss of
millions of dollars, the state sponsored the Patuxent "Charrette" in 1981, a
historic conference organized by Mr. Eichbaum. Using a time-constrained,
conflict-resolution process to reach a consensus, the stalemate was broken,
laying the foundations for the Patuxent River Nutrient Control Plan for
controlling both point and nonpoint inputs of N and P. Like the Potomac
plan, the Patuxent plan set limits on total N and P loadings to the river as a
whole, and, again, economics was an important factor. Unlike the Potomac
plan, which was restricted to the tidal freshwater reach of the system and
was formulated quickly in response to new scientific information, the Patuxent
plan was truly basinwide and took a decade of struggle and confrontation to
develop.
Control of Nonpoint Source Nutrient Loading
A major event occurred in June 1972 that would have a delayed but
dramatic impact on the subsequent course of nutrient research and manage-
ment throughout the Chesapeake region. Hurricane Agnes arrived, inundat-
ing the watershed with up to 18 inches of rainfall.4 The watershed as a
whole (64,000 square miles) received over 5 inches in less than three days.
Agnes served as a "lightning rod," focusing research activities on a number
of important questions, including the response of the Bay and its tributaries
to nutrient enrichment (Cheaspeake Research Consortium, 1976~. (The im-
mense amount of water runoff carried with it large amounts of nutrients
from nonpoint sources such as fertilizers and animal wastes.) The storm
demonstrated the systemwide susceptibility of the Bay to nutrient enrich-
ment. Major findings included large increases in nutrient levels caused by
high runoff and erosion, and the realization that most of the large quantities
of nutrients delivered to the Bay are retained within the Bay (rather than
being exported to the ocean). Much of the nutrient input entered the sedi-
ments and was released during subsequent years, resulting in unusually high
phytoplankton production (Boynton et al., 19821. In effect, Agnes brought
important environmental issues before the public and primed the science
and management communities for what was to become the EPA's Chesa-
peake Bay Study.
Clark et al. (1973) made an early assessment of nonpoint nutrient inputs
in the Chesapeake watershed. They reported that N runoff from agriculture
was more than an order of magnitude higher than that from forested areas.
These results were reflected in Maryland's 1975 report to EPA (as required
by the 1972 CWA), which emphasized point source inputs but also acknowl-
edged that, "The heavy use of fertilizers and manure on the land results in
some runoff to the streams." In 1977 the National Science Foundation
,
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18
MALONE, BOYNTON, HORTON, AND STEVENSON
(NSF) sponsored a major workshop on watershed research in North America
at the Smithsonian Center for Chesapeake Bay Research in Edgewater, Maryland.
Results presented at the workshop confirmed that nonpoint N inputs were a
major, if not the dominant, term in the N budget of the Bay. Although
managers from both state and federal agencies attended the watershed
workshop, more than a decade would pass before this reality would begin
to be incorporated into a management scheme specifically directed at nu-
trient control. There was strong resistance by the management community
in general, and by agricultural interests (both scientists and managers) in
particular, to the idea that farming practices are related to nutrient loading
and water quality in the Bay. This resistance was expressed by the Secre-
tary of the Maryland Department of Natural Resources (DNR), James B.
Coulte.r, who in referring to nonpoint nutrient sources, was quoted as stat-
ing that, "There is more alarm than is necessary; it can be controlled with
just good housekeeping and old fashioned general sanitation" (Baltimore
Sun, February 7, 19771.
Unfortunately, this "common sense" approach relied heavily on best
management practices (BMP), which were intended primarily to minimize
the loss of soil and thereby increase or sustain agricultural productivity.
Because most P enters the estuary attached to particles, one by-product of
this strategy has been to reduce nonpoint inputs of P. Despite earlier warn-
ings (Walter et al., 1979) and information on loading rates (Jaworski, 1981)
that indicated that BMPs derived from soil conservation would have little
impact on dissolved nutrients such as N. management planning continued to
stress problems of erosion, with little consideration for nutrient control per
se. The significance of this was highlighted by studies in the Choptank
River basin (on the eastern shore of the Bay), which indicated that nonpoint
sources account for about 80 percent of N and 60 percent of P inputs (Lomax
and Stevenson, 1981~. The emphasis on point-source nutrient control would
not begin to change until after the release of the results and conclusions
from the Bay Study in 1982 and 1983.
The fact that the Bay is imbedded in a large watershed (about 28 units
of land area for each unit of Bay surface area), which was being rapidly
modified by human activities, was not generally a part of management or
scientific thinking at the time. Management was focused on point-source
discharges, and funding for research tended to focus the science community
on the effects of sewage and thermal discharges. The problems of overenrich-
ment were thought to be restricted to a few local tributaries such as the
upper Potomac and Patuxent River estuaries, where point-source inputs were
clearly related to the degradation of water quality. Despite the effects of
Tropical Storm Agnes and subsequent research findings, the baywide im-
pacts of nonpoint nutrient loading were not broadly appreciated at this time.
Agnes planted the seeds, but serious attempts to understand and control
.
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28
MALONE, BOYNTON, HORTON, AND STEVENSON
by public and political pressures precipitated by local water quality prob-
lems that did not require sophisticated tools of science to uncover. The
relationship between point source inputs and water quality (as indicated by
such phenomena as red tides, noxious odors, and fish kills) was usually
obvious, and it was generally assumed that nutrient loading could be man-
aged through secondary treatment to control point source loadings. Man-
agement moved out in front of the science and formulated their own "best
guess" scenarios as to the degree and kinds of nutrient reductions needed to
improve water quality.
The Potomac case may be considered an exception in this regard. Sci-
entific research preceded management action, which appeared to be closely
coupled to new scientific information establishing quantitative relationships
between nutrient loading and water quality. Low rainfall during the 1960s
undoubtedly exacerbated conditions in the Potomac River where noxious
algal blooms, fish kills, and generally unsanitary conditions were occurring
at the doorstep of the White House. Here, secondary treatment and ad-
vanced wastewater treatment for P reversed the trend of declining water
quality, at least in the tidal freshwater reach of the estuary (Jaworski, 1990~.5
However, the Potomac case was unique, not only in terms of the apparent
close coupling between new scientific information and management action
(which probably reflected the river's proximity to Washington, D.C., and its
role as a political showcase as much as anything else), but also in terms of
the massive expenditure of federal funds (about $1 billion) and its limited
impact on research and management in the greater Chesapeake Bay region.
A fundamental change in the relationship between science and manage-
ment began to emerge with the controversy over N control in the Patuxent
River basin. The spatial displacement between the upstream location of
point source nutrient inputs and downstream effects not only set the stage
for a decade-long debate over the control of N and nonpoint source inputs,
it marked the beginning of a systemwide approach to the problem of eutrophica-
tion in the Bay and its tributaries. With this seed, the connection between
nutrient loading and water quality in the Bay as a whole began to crystalize
when research sponsored by the EPA Bay Program related widespread de-
cline of SAV to overenrichment. At this point, science began to move out
in front of management, in part because of the complex nature of the prob-
lem and in part because of the lack of funding (including financial incen-
tives from the federal government) to develop and implement new approaches
and technologies required to address the problems of N and controlling
nonpolnt source inputs.
The management community as a whole did not acknowledge the need
to control N and nonpoint source inputs until the late 1980s when the cumu-
lative impact of evidence from environmental research became overwhelm-
ing. With each iteration of nutrient inventories and budgets, the predomi
.,
..,
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CHESAPEAKE BAY CASE STUDY
29
nance of nonpoint sources became unequivocal. The shift from P to N
limitation along the transition from fresh to salt water areas was clearly
demonstrated. Studies of benthic nutrient fluxes revealed that models of
water quality in the Bay would have to incorporate benthic-water column
interactions into their calculations; large-scale baywide studies revealed the
mechanisms by which nutrient inputs cause oxygen depletion in the main
Bay, and showed that nonpoint sources were the principal cause; and cur-
rent soil conservation practices were shown to have little effect on N input
to the Bay. These advances could not have been made without a major
research and monitoring effort by the science and management communities
in the Chesapeake Bay region. Rather than depending on science informa-
tion generated by research in Canadian and European lakes, the manage-
ment process was increasingly guided by new scientific information on the
Bay itself, information that currently influences nutrient management in
estuarine systems worldwide.
Explicit actions to control N loading have been limited to point source
discharges to the upper Potomac and Patuxent rivers, and strategies that
target nonpoint sources of N are only now being seriously considered. On
the receiving end, the 1992 Bay Agreement identifies the return of SAV as
an initial measure of the effectiveness of nutrient management in the resto-
ration of living resources and water quality. Long lags (on the order of 10
years or more) between scientific discovery and management action are a
common feature of each of these cases. To some extent, this reflects a
considered and informed decision-making process related to social and eco-
nomic considerations and to the uncertainty of environmental science. However,
the record also suggests that this is often not the case, in part because
sufficient information is simply not available (increasing the uncertainty),
but also because of ineffective information exchange between the science
and management communities. Consequently, delays in the use of new
scientific information are often related more to politics and economics (compare
the histories of point source nutrient control in the Potomac and Patuxent
cases) than to the quantity and quality of available information. As clearly
stated by Ian Morris, the director of the Center for Environmental and Es-
tuarine Studies of the University of Maryland (Baltimore Sun, July 17,
1983), "There is nothing wrong with forging ahead before knowledge of a
problem is complete fbecauseJ it never is but you need to keep close touch
with good scientific study, and that close touch is being lost." A compara-
tive study of coastal seas management in different regions from the Baltic
Sea to the Inland Sea of Japan clearly shows the importance of "indepen-
dent but relevant science" to the decision-making process (Morris and Bell,
1988~. This study suggests that, although new scientific information rarely
initiates management action, the availability of good information and scien-
tific advice not only enhances the responsiveness and quality of manage
. ..~
. ._
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MALONE, BOYNTON, HORTON, AND STEVENSON
ment actions but also often reinforces management decisions and helps keep
the management process one-track.
Sources of Inertia
Inertia in the management process occurs for a variety of reasons that
range from the sheer magnitude of the problem and the cost of solving it to
poor problem definition, uncertainties inherent in the prediction of ecosys-
tem behavior, and polarization between the science and management com-
munities. Two features of the Chesapeake Bay experience that exemplify
magnitude and cost stand out: the need for more STPs with advanced waste-
water treatment and the need to control nonpoint sources. Clearly, reliance
on a particular technology (secondary treatment) as the basis for regulating
nutrient inputs has inhibited the development of alternative (less costly,
more effective?) approaches and technologies (see Officer and Ryther, 19779.
Furthermore, as the fiscal realities of advanced wastewater treatment for P
removal became apparent in the 1970s, the Congress and the General Ac-
counting Office became alarmed and instituted a federal "Advanced Waste-
water Treatment Policy," which essentially subjected STPs contemplating
advanced P or N removal to extreme scrutiny. The effect was to create a
powerful disincentive for advanced wastewater treatment, especially for N.
Consequently, STPs on the Patuxent did not begin to remove nitrogen until
1991, several years after cost-effective technology became available, a de-
cade after the Patuxent Charrette, and more than two decades after scientists
first began to worry about N loading to the Bay.
In the case of nonpoint sources, their diffuse nature and relationship to
patterns of landuse catapulted the problem of nutrient regulation to a new
level involving not only water quality and living resources but also socio-
economic forces related to population growth in the watershed. Implemen-
tation of point source controls has little direct impact on the social fabric of
the population, and the costs of reducing point source inputs can be pre-
dicted with a relatively high degree of certainty based on knowledge of
loading rates and the required technology. This is not the case for nonpoint
inputs. Management of nonpoint sources inevitably leads to conflicts be-
tween prevailing patterns of land use (by farmers, homeowners, industry,
government, etc.) and the implementation of nutrient control schemes. The
cost of reducing nonpoint sources is more unpredictable because of uncer-
tainties in loading rates and in the effectiveness of different methods of
nutrient control. Thus, for justifying the social and economic costs of
nutrient management, it becomes much more important to demonstrate cause-
effect relationships between nonpoint sources, water quality, and the capac-
ity of the ecosystem to support living resources. Decision makers insist on
more information before implementing control measures.
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CHESAPEAKE BAY CASE STUDY
31
Scientists and managers typically function on different time scales, re-
sulting in tension and distrust between the two groups, which in turn inhib-
its effective exchange of information and consensus on problems and their
solution. For the most part, environmental scientists are cast in the role of
conducting research intended to further our understanding of nature. Ad-
vances occur on time scales that are dictated by factors ranging from the
peer review process to the variability that characterizes populations of or-
ganisms, the ecosystems within which they function, and the climatic fac-
tors that perturb them. In contrast, managers are expected to make in-
formed decisions and solve problems in a "timely" fashion and are often
under considerable pressure to do so on political time scales that are short
relative to the generation of new scientific understanding. To compound the
problem, success in the science community is achieved through a process
that emphasizes peer review, so there is little motivation to communicate
outside the science community (except when funds are needed for research).
Within the management community, success is measured, in part, by the
outcome of the decision, which typically must be made before sufficient
scientific information is available. The distrust that these dichotomies and
lack of communication breed has two important and related consequences:
(1) the management community tends to question the relevance of environ-
mental research conducted by an independent science community, and (2)
the science community tends to question the integrity of the management
process.
Free from the requirement to make management decisions, scientists
are much more likely to acknowledge uncertainties and the complexities of
nature. For example, consider an event that occurred in 1983, the year of
the first Chesapeake Bay Agreement. A headline in the Baltimore Sun (July
17, 1983) reads "Scientists Wary About Quick Fix for Bay." The article
quotes a prominent university scientist as stating in testimony before the
state Assembly that "we still don't know very much about nitrogen and the
Bay.... The nitrogen entering the bay from farm runoff may not be as
injurious, pound for pound, as that coming from . . . sewage treatment
plants.... Buffer strips may not stop much nitrogen from running off farms
. . . the bay is not purely a sink [for N. which can escape the Bay in gaseous
form]." This left "decision-makers upset and confused . . . some almost
cursing, 'saying what is this guy trying to do to us?"' A manager with the
Maryland DNR summed up the dilemma by commenting that, "Scientists,
being quite honest. present so many options that no action nets taken . . .
, .L ~
which Is our problem as managers who must take action." In a subsequent
interview, Tom Horton of the Baltimore Sun (personal notes) quotes Secre-
tary Eichbaum as saying "Ian's tIan Morris] concerned about a lack of
communication between scientists and us? I know he feels that way and I
think he's even right, but in most of our experiences in the bay system the
-
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MALONE, BOYNTON, HORTON, AND STEVENSON
scientists have not provided answers as to what to do. They have sat around
and complicated the issue, and that's the nature of their job. So at this stage
fin the management process] it's not so unusual for scientists to recede into
the background. Hopefully, the information they've given us is good enough."
The uncertainties and complexities (large data sets) inherent to environ-
mental science have also led to, arguably, an irrational reliance on math-
ematical models as predictors of ecological variability and responses to
anthropogenic perturbations. This tendency of the management community
to view water quality models with considerable favor is understandable.
Scientists who develop the models have a vested interest in seeing them
used (an example of why it is important to maintain a separation of pow-
ers in terms of the generation of scientific information and its use by
management). At the same time, they provide an objective means of
synthesizing a great deal of information and of predicting both the causes
and the consequences of eutrophication (in this case), and they take the
"heat" off the decision maker (the model makes the decision). This allows
the government to assess blame and institute corrective actions. Herein
lies the rub. All of these are attractive (and seductive) features, but all
assume that the water quality model provides an accurate representation of
the real world.
The current heavy reliance on the 3-D, time-dependent, coupled hydro-
dynamic water quality model to set nutrient reduction goals and evaluate the
success of nutrient control programs is reminiscent of the Patuxent experi-
ence. Clearly, this model is significantly improved, but it is still an imper-
fect cartoon of the real world. It is so tempting to ask the model a question
and then believe the answer ("mirror, mirror on the wall") when the most
prudent approach is to use the model results in conjunction with other sources
of information (monitoring and experimental results that reveal causation).
One must also keep in mind that no single model can answer all questions.
For example, the current model does not address the dynamics of littoral
areas, sea grasses, or food webs. Finally, models may take many years to
develop, during which time the playing field and the players may change,
including expectations of what the model can and cannot do. The original
intent of the model may be modest (e.g., to be used as a trial-and-error
tool), but as the results are simplified again and again for nontechnical
audiences, expectations can and do become unrealistic. As the cost of the
model increases (in terms of time and money) and the corporate memory is
lost, the model begins to take on a life of its own and the predictions
become reality. Thus, there is a tendency for the management community
to reach the conclusion that additional scientific information is no longer
needed, a tendency that can be countered by establishing a process of peri-
odic scientific reevaluation of the effectiveness of management actions.
...
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CHESAPEAKE BAY CASE STUDY
33
Overcoming Inertia
Clearly, financial incentives in the form of federal and state funding for
such actions as the construction of STPs and the implementation of BMPs
have played an important role in controlling nutrient loading to surface
waters. However, the authorizing legislation and subsequent appropriations
are often responses to an environmental catastrophe. In a recent study of
the process of environmental governance, Morris and Bell (1988) argue the
case that a "major event" is required to stimulate policymakers and manag-
ers to take action on environmental issues. They suggested that, in the
Chesapeake Bay region, this event was the Chesapeake Bay Study itself.
Our analysis certainly supports this contention. By pulling together large
numbers of scientists and decision makers from throughout the Bay and its
watershed, the EPA Bay Study marked a significant departure from the
course of the 1960s and 1970s. Under the auspices of the EPA, it gave rise
to a governance structure that would involve citizens, government officials,
and scientists in the oversight of environmental research, formulation of
policy, and implementation of that policy throughout the entire Bay and its
watershed (the Chesapeake Executive Council, Citizens Advisory Commit-
tee, Science and Technology Committee, and Implementation Committee).
This spawned a decade of research and management activity that was un-
precedented in the United States, and ushered in an era that would lead to a
more systemwide perspective as the significance of nonpoint sources and
water movements through drainage basins and the estuaries of the Bay be-
came increasingly apparent.
Our analysis also suggests that Tropical Storm Agnes was an event of
similar impact, which, in effect, set the stage for the EPA Bay Study. Agnes
alerted a broad cross-section of the population, including scientists and
managers, to the systemwide susceptibility of the Bay to inputs from land.
Until Tropical Storm Agnes arrived in 1972, research tended to focus on
local problems, a tendency exacerbated by the funding priorities of manage-
ment agencies that emphasized the effects of power plants, oil spills, and
dredging. Pritchard (July 1, 1970, Baltimore Sun) states that, "The empha-
sis on thermal pollution is obscuring the real threat to the Bay, nutrient
pollution." This 200-year storm captured the attention of the entire popula-
tion of the Chesapeake region, including state and federal agencies, elected
officials, concerned citizens, and the scientific community. In a terrible
way, Agnes reconnected millions of urban and suburban dwellers to nature.
People were made keenly aware that they did not just live on a street or in a
town, but also in the drainage basin of a creek, in the valley of a river. The
storm dramatized how we had changed the very nature of the watershed in
just a few decades, stripping the vegetation that once covered it and ab-
sorbed and slowed the runoff of rainfall, paving it for roads and parking,
.
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MALONE, BOYNTON, HORTON, AND STEVENSON
and roofing it over with homes. One effect of these land-use patterns was
to channel the water that fell with a destructive force never seen before. In
retrospect, it is clear that, although the storm delivered a "bullet to the
Bay's heart," land use in the watershed had been "loading the gun and
softening up the victim for many decades."
The precedent-setting 1981 Patuxent Charrette and the Chesapeake Bay
Agreements that followed illustrate the importance of achieving a consen-
sus involving a broad cross-section of a region's social fabric. Events
leading up to the Patuxent Charrette and the Charrette itself underscore
some of the ingredients needed to achieve a consensus on the nature of the
problem and the actions that need to be implemented to solve the problem.
Among the more important of these are leadership, trust, and financial in-
centives. A few powerful individuals had to have more than a passing
interest in the problem; they needed to understand the problem well enough
to justify action in the context of competing political, economic, and social
forces. Such leadership was clearly demonstrated by the actions of Senator
Mathias, who formulated the legislation that led to the EPA Bay Program;
by Senator Fowler, whose environmental concerns led to a nutrient manage-
ment plan for the Patuxent River basin; and by the state governors who had
the foresight to look beyond their borders in agreeing to clean up the Bay.
The Patuxent case in particular illustrates the need for trust. It is unlikely
that a truly comprehensive nutrient management plan for the Patuxent River
basin would have been agreed upon if it were not for a clear definition of
the problem, the establishment of common goals, the existence of indepen-
dent scientific advice, and mutual respect among the participating parties.
In this regard, the university was viewed by Senator Fowler and his associ-
ates as a source of information from a disinterested party, an "honest bro-
ker." This was critical, as was the presence of managers within the Mary-
land state government who were willing to listen and even fund research
that could (and did) produce evidence that the state and the EPA were
wrong in insisting that N loading was not a problem (D'Elia, 1987; D'Elia
et al., 1986~.
The main impact of these actions and the "major" events that gave rise
to them was to raise the plight of the Bay to a new level of public and
political consciousness. In this context, it is important to note that, al-
though there were (and are) few who would take exception to the course set
by the 1983 Bay Agreement, important decisions were made on the basis of
relatively little scientific information decisions that would have profound
social and economic consequences. Agreements were consummated by high-
ranking government officials based on perceptions and the "common sense"
of the day. The impact of the EPA Bay Study was not related as much to
new scientific information as it was to the large number and diversity of
individuals and institutions involved in the process. The real genius of the
Or
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CHESAPEAKE BAY CASE STUDY
35
study was in synthesizing and disseminating existing environmental infor-
mation and scientific understanding, and in providing the political climate
needed to galvanize decision makers throughout the Bay's multistate water-
shed. The process itself, rather than the information it produced, led to the
Bay Agreement and launched an unprecedented period of legislative, man-
agement, public, and research activity.
NOTES
1. The degradation of water quality occurs when assimilation capacity is exceeded. The
degradation is expressed by such phenomena as accumulations of algal biomass, noxious algal
blooms, decreases in water clarity, depletion of oxygen, and related losses of plant, animal,
and insect life.
2. Environmental research is defined as activities that generate technical information about
nutrient enrichment upon which the management of nutrient inputs can be based. Management
is considered to be primarily a government activity that includes the formulation of environ-
mental policy, regulations, and agreements.
3. The term anthropogenic is generally used to identify sources of pollutants that stem
from human activities manufacturing, farming, waste disposal, etc. For purposes of this
analysis, anthropogenic nutrient inputs include inputs from point sources (such as wastewater
discharges) and diffuse sources (for example, runoff from agricultural development, atmo-
spheric deposition).
4. Hurricane Agnes caused devastating coastal flooding from Florida to New York. By the
time the storm reached Chesapeake Bay, it had been downgraded to the level of a tropical
storm.
5. A massive nuisance bloom of blue-green algae in the upper Potomac in 1983 was attrib-
uted to a combination of events that resulted in the release of excess phosphorus from the
sediments (Jaworski, 1990).
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Representative terms from entire chapter:
water quality
