The Nation\'s River
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United States Department of the Interior >> The Nation\'s River
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[Illustration]
The Basin has several standard sorts of pollution, often found in one
combination or another. Chemical contamination occurs along the North
Branch, in areas where pesticides and other economic poisons get into
the stream system, and in spots and stretches where specific industrial
wastes create local problems. There is much and widespread pollution
through organic wastes--often sewage solids, but not always--whose
breakdown by natural processes may demand so much oxygen that a stream
has little or none left over to maintain aquatic life and "stay alive."
Sometimes associated with organic wastes and sometimes entering the
river system otherwise are dangerous bacteria, and also the so-called
"nutrients"--dissolved fertilizing agents that can stimulate excessive
growth of algae or weeds in the water to the detriment of other forms of
life, often to such a degree that these plants' death and decay sets off
a whole new cycle of oxygen demand. And there is sediment washed off the
land, which clouds the water and settles out into a smothering cloak on
the bottom, building up in quiet stretches into ugly and damaging mud
banks and shoals.
Troubles above the Fall Line
Pollution of the Potomac begins at or near its traditional source, the
tiny Appalachian spring at the head of the North Branch where in 1746
Thomas Lord Fairfax's surveyors set an inscribed stone to mark the
northwestern corner of that possessive nobleman's vast holdings.
Abandoned strip coal mines lie within sight of the spot, and it is
doubtful that the infant river trickles more than a few yards before
receiving its first injection of the acidic mixture of substances that
springs and seeps and runoff water extract from bared coal strata and
the mines' spoil heaps and carry down to the streamlet they feed.
[Illustration]
Such additions are frequent for the next 45 miles or so downstream, as
the North Branch in its narrow valley swells into a mountain river with
the water of brooks and creeks flowing off ridges pocked with coal mines
old and new. The river and such tributaries sustain no aquatic life at
all among the discolored stones in their channels.
This mine-derived pollution has been much studied but is still not well
understood. Sulphuric acid is its most damaging component, but may be
accompanied by iron salts and other substances also leached from
materials in and around the vast coal beds of Appalachia. Some acid
entered the streams there naturally, before men ever touched the coal,
but it has increased to deadly proportions with widespread mining. It
issues from both surface strip mines and the old-fashioned underground
sort, though the latter furnish by far the most--an estimated 75 to 90
percent. The overall magnitude of the problem is indicated by the fact
that the more than 60,000 square miles of the Appalachian region
underlain by coal, including the Potomac fraction, contributes five to
ten million tons of sulphuric acid annually to streams and rivers, a
rate of production that is expected to continue for at least a thousand
years.
At Westernport the North Branch enters more populated realms, and
receives one of its latter big doses of acid from Georges Creek, which
drains a devastated, economically depressed valley mined since very
early days. This creek may be the single most unfortunate stream in the
Potomac Basin, for the accumulation of raw wastes it brings down from
the valley's communities is pickled rather than assimilated by its
heavily acid water.
[Illustration]
In the 40 or 50 miles below that point, the North Branch accumulates
great quantities of more usual kinds of pollution as it runs down a
broadening valley past towns and industries that have grown up because
of the conjunction of coal, timber, water, and railways--and in the old
days water transport, for flatboats used to shoot the river at high
water, and later the C. & O. Canal operated upriver as far as
Cumberland. Treatment of wastes in this reach is spotty and mainly
inadequate. Some industries and towns sluice them raw into the dark, sad
water, and others give only perfunctory primary treatment; the city of
Cumberland releases the equivalent of about 18,000 persons' body wastes
each day as effluent, besides extra raw wastes whenever storm runoff
overloads its combined storm and sanitary sewer system and causes it to
overflow. Where major efforts have been made, as at the Upper Potomac
River Commission's Westernport plant below the big Luke, Maryland, pulp
and paper mill, the wastes are so voluminous and complex that some of
them still have to be dumped, and the effluent from even highly
efficient treatment further degrades the river.
Fortunately, the North Branch, acid above, deprived of oxygen and
overenriched and septic below, is not typical of the flowing parts of
the Potomac river system, but it stands as a good grim example of what
pollution can mean, and as a foretaste of what may be expected to happen
elsewhere in the Basin if it is not stopped soon. Mine acid is not a
significant problem in any streams outside of that region, but untreated
or inadequately treated wastes are badly blighting many streams and
rivers or stretches of them. Some smaller watercourses, like historic
Antietam Creek below Hagerstown, Maryland, have deteriorated under the
influence of discharges from single or limited sources, while larger
ones suffer from a cumulative waste buildup in areas of concentrated
population or industry. Some twenty miles of both industrial and
municipal pollution in the South River Branch of the Shenandoah's South
Fork below Waynesboro, Virginia, have done much damage to that legended
river for a good distance downstream, a situation that is worsening with
the area's growth. On the North Fork of the Shenandoah similar effects
have been wrought by heavy organic loads from poultry processing and
other things. The list could be extended: aside from a few happy
exceptions like the prized Cacapon, draining rugged, forested, thinly
peopled hill country, nearly all the Basin's flowing streams of any size
receive damaging loads of waste from towns and industries.
[Illustration: WATER TREATMENT STEPS
(1) River water enters here
(2) Water chlorinated
(3) Water settles. Heavy particles sink
(4) Water pumped to Pretreatment Building
(5) Various chemicals (chlorine, alum, lime, carbon) added. Chemicals
and water stirred in rapid mixing basins
(6) Slow mixing to form "floc" (see Alum below)
(7) Water settles for 2-1/2 hours. "Floc" carries impurities to bottom
(8) Water filtered through 94 rapid sand beds
(9) Final chemical treatment (chlorine, lime, fluoride, phosphate)
PURPOSE OF CHEMICALS
CHLORINE: Destroys organic materials
PHOSPHATE: Lessens pipe corrosion
FLUORIDE: Lessens tooth decay
CARBON: Controls taste and odor
ALUM: Forms "floc" (snowflakes) to trap impurities
LIME: Helps "floc" formation; lessens pipe corrosion
]
The basic and usual damage comes from oxygen depletion. A stream has a
natural capacity for hastening the decay of organic wastes, which is
determined by such things as the volume of its flow, the pollution
already in it, its velocity and depth, and its temperature. When that
capacity is exceeded, as we have noted, too much of the stream's oxygen
is used up by the process of decay and the stream, which is an
intricately complex work of living things, begins to die. Under really
bad conditions, the waste solids themselves cannot all be assimilated,
and hence may build up in layers of stinking sludge at the bottom of
the stream and continue to seize available oxygen for a long time
thereafter.
Conventional waste treatment, in plants built by towns or by industries
whose raw materials are animal or vegetable in origin, is aimed at
removing the solids in the wastes and reducing the bio-chemical oxygen
demand--called B.O.D. It is a speeded-up version of the same process of
purification that goes on normally in any stream when loads are not too
heavy. "Primary" treatment removes such solids as will readily settle
out and passes the rest on back to the stream as part of the effluent.
"Secondary" treatment plants, after settling out the gross solids, speed
up decay by furnishing air to the bacteria that eat up dissolved and
finely suspended materials; a good secondary plant, under much more
skillful supervision than is usual, can get rid of 85 or 90 percent of
the organic materials and the associated B.O.D. by the time it turns its
effluent into a stream. How damaging that effluent will be depends on a
number of things, chief among them being the size and condition of the
receiving stream and the volume of organic materials that went into the
treatment plant in the first place. A riverside town of 1000 with a
secondary treatment plant operating at 75 percent efficiency is going to
inflict on its river a daily load roughly equivalent to the raw sewage
from 250 people.
Over the years a lot of hard effort, notably on the part of the
Interstate Commission on the Potomac River Basin, has resulted in some
degree of treatment for about 85 percent of all municipal wastes and 83
percent of those produced by industry along the Basin's flowing
streams. Put in another way, by INCOPOT calculations the total waste
load imposed on the Potomac is only about three-quarters of what it was
in 1956, despite a population increase of nearly a fifth.
That it is still much too high in many parts of the upper Basin does not
require elaborate instruments to detect, but only a nose and a pair of
eyes. A very few industries and towns are still dumping raw wastes, and
many of the others need better and bigger sewers and treatment plants or
better operation of the plants they have. Sewage collection systems are
sometimes of the old-fashioned combined type, like Cumberland's--and, as
we shall see, like Washington's--which have to carry storm runoff as
well as wastes, and overflow during rainy periods, releasing heavy
pollution without treatment. But even separate sanitary sewers are often
overloaded by having to serve greater populations than they were
designed for, which means that their escape valves may leak raw sewage
more or less continuously into surface watercourses and that the quality
of treatment given the sewage that does reach the treatment plant
signifies less than it ought to.
Antiquated or overloaded treatment plants cause much trouble. Old
primary plants too small for present populations often remove only about
a third or less of the organic material, but by their very existence
they tend to lull communities into a false conviction that they are
doing their part toward clean rivers. Tiny plants of the sort authorized
locally for new leapfrog subdivisions and vacation colonies are usually
doomed to restricted efficiency by their very size. These often are
underdesigned even for initial loads, let alone for the growth that
comes later, and most of them are poorly run.
This question of operation is crucial. A new, well-designed, expensive
plant in slovenly or inexpert hands--a frequent paradox--can put out a
much greater waste load than a well-operated old one. The plant at
Romney, West Virginia, on the lower South Branch, the best example of
responsible operation in the Basin, is old, but because it is well run
it usually achieves about 92 percent elimination of B.O.D. in comparison
with the 75 percent or even less that some newer and more imposing
plants can claim.
The reasons for poor operation are various. One is a shortage of
qualified operators, based on a need for better salaries, more training
programs, and rigid mandatory State certification of operators'
abilities. Another reason can be a pinchpenny attitude on the part of
municipal authorities toward sewage treatment. It is one sizable
expenditure whose results cannot easily be pointed out with pride to
local taxpayers at election time, for its main effect is usually
downstream from the municipality itself. Thus the big encompassing
reason for bad plant operation--cutting corners, refusing to spend what
needs to be spent, failing to supervise--has to be called philosophical.
It comes from a failure on the part of local operators and authorities
and much of the public to comprehend the immorality of deliberate
avoidable pollution, and it may mean that municipal operation of
treatment plants is itself often a major source of trouble.
A clear example of this philosophical deficiency is one large Basin
treatment plant that was reported to have "handled"--i.e., properly
disposed of--a third less sewage sludge in 1965 than it had in 1960,
despite a large increase in the population it serves. The unhandled
sludge, of course, went straight into the local river for reasons of
convenience, economy, and callous indifference.
For the most part, large private industry demonstrates more
responsibility in this respect than the Basin's municipalities or
Federal installations. There are some miserable exceptions where
individual industries dominate a locality's economy and take casual
advantage of that fact. But responsible industry is concerned with
public relations, and knows that a fish kill or a gray-blue stretch of
blighted water downstream from its outfalls is the poorest kind of
public relations to be had.
To be able to say precisely how much bad plant operation is adding to
pollution in the Potomac will require exhaustive and continuous sampling
and analysis of a kind that may be expected now that the Water Quality
Act of 1965 is about to make itself felt through application of new
State water quality standards. But experienced observers in INCOPOT and
elsewhere feel strongly that bad operation does much more damage than do
over-aged or outgrown facilities, though these play a big part too.
Bacterial pollution--the category of most interest from a public health
standpoint--fluctuates a great deal in the Basin's flowing streams, but
is heavy in most of them by current standards during times of normal
flow. It may come from raw waste discharges, from treatment plants that
skimp on chlorination of their effluent, or from storm runoff and
natural drainage off the land and urban pavements. But before anyone can
confidently say how dangerous it is to swimmers and others who make
intimate use of rivers and creeks, water scientists are going to have to
learn more about its measurement and classification than they presently
know.
[Illustration]
No easily applied method of testing can effectively establish the
guaranteed absence of human disease germs. The traditional "Coliform
Count" plays safe, as it must. It measures the concentration of certain
easily spotted "indicator" organisms that do not themselves make people
sick but are always voluminously present in the fecal discharges that
can carry harmful germs, and it gauges the danger by the concentration
of these indicators.
However, concentrations of coliform bacteria, originating in animal
manure or elsewhere, may invade a stream through runoff from rural lands
without having any meaningful relationship to human disease germs.
Counting them under such circumstances is a little like measuring the
depth of the proverbial well by the length of the pump handle.
Furthermore, no one really knows how easy or how hard it may be to catch
given diseases by swimming. In this country, outbreaks of leptospirosis,
an illness common to man and certain animals, have been traced to
swimming holes, and other links are obvious. On the other hand, some
careful British investigations turned up a good many quite healthy
people who habitually splashed about in sea water teeming with
pathogenic organisms of one sort or another. Sea water and fresh water
have vastly different qualities, but the subject is presently full of
confusion, and it needs much research.
Land runoff in general furnishes a large amount of pollution of all
classes, and in all parts of the upper Basin except the least-used
forest sections. Besides bacteria, heavy loads of organic material may
be washed into streams in regions with high densities of livestock or
poultry, and some pollution of this sort is found practically
everywhere. The wild and domestic animal population of the Basin above
Washington has been estimated to produce wastes equivalent to those of
about 3.5 million people. Much of this is dealt with by the "living
filter" of the soil, but much also reaches the streams, associated with
sediment from erosion producing rains. And the sources, particularly in
areas such as those along the Shenandoah and the Monocacy and other
streams with wide rich valleys, are numerous and diffuse.
Nitrogen and phosphorus nutrients, which foster weeds and slime in quiet
stream stretches and contribute to the problems of the estuary
downstream, are found in undesirable concentrations in most of the
Basin's waters above the Fall Line. Not only are the growths encouraged
by these fertilizing agents ugly, but they also upset the ecological
balance of streams by favoring certain types of aquatic life over
others, and they can cause tastes, odors, and clogging in water supply
systems and sometimes, by rotting, a secondary sort of oxygen
deficiency. Nitrogen and phosphorus occur in the effluent from waste
treatment plants, for they are present in human wastes and in
detergents, and in dissolved form are little affected by standard
treatment processes. And in the upper Basin a large part of the nutrient
load in streams appears to be associated with sediment from the same
diffused land runoff mentioned above, for they occur abundantly in
manure, in synthetic fertilizers, in certain natural soils, and in
decaying organic substances of many kinds. The health and growth of
living things is dependent on these elements, of course; it is their
excessive release into waters that causes trouble.
From the same farming regions and even more from lawns and gardens and
parks in more populated areas, pesticides and other economic poisons
accompany sediment into the stream system or are blown into it as
sprays and dusts. They seem not to be as great a problem in the Potomac
as in some other rivers, but they are present in probably significant
amounts; indicator tests hover near Public Health Service drinking-water
limits in the river. Their use, here as elsewhere, increases year by
year, for they are tremendously effective against many of man's ancient
enemies. Being easily available, they are often used in uninformed and
careless ways despite government efforts to determine and publicize safe
levels of application. Knowledge about their side effects, both
immediate and long-term, is still full of gaps. Badly misused, they are
obviously dangerous. But information about the precise results of their
ordinary use and their buildup in nature accumulates very slowly.
The persistent chlorinated hydrocarbons--DDT and its relatives--last for
a long time after being released into the environment, concentrating at
various points in the natural food chain and often in man himself. It is
said that an average adult Californian's tissues today contain more DDT
than is allowed in beef for interstate shipment. But no one is yet
certain what this means in relation to that average Californian's
physical wellbeing, and in terms of fish and wildlife, though the link
between these materials and certain destructive changes can be seen,
evidence in other cases--the declining fertility and numbers of bald
eagles, for instance, which some investigators believe to derive from
pesticide residues--only points toward such a link. Until all the facts
are in and the impact of such poisons has been clearly restricted to the
pest species at which they are aimed, they are going to continue to be
a heavy concern for conservationists and others alarmed about
environmental pollution, along the Potomac and elsewhere.
[Illustration]
[Illustration]
One of the principal Potomac pollutants, silt, not only comes from the
land but is the land, most often good topsoil, washing away toward the
sea. Even under pristine conditions streams are likely to run somewhat
muddy after storms; it is a natural phenomenon, a by-effect of the way
climate carves landscapes. On the evidence, however, the Potomac
landscape since its colonization by white men has been undergoing a much
more rapid carving than anyone could consider to be natural. Most of its
streams, particularly in their lower reaches, are thickly opaque for
long periods after rain, and gross erosion in the Basin--the amount of
soil washed away from where it usefully belongs to somewhere
else--averages about 50 million tons per year, a major depletion of the
soil resource and a degrading influence on the landscape through
erosion. The part of this silt that gets into streams cuts down on the
usefulness of the water, creates ugly turbidity, chokes quiet pools and
reservoirs, suffocates bottom-dwelling creatures and plants on which the
streams' wholeness may depend, and rides down the current to add heavily
to the problems of the estuary, into which some 2.5 million tons of it
are annually discharged.
Sediment is dislodged from the land by the pounding action of raindrops
and the flow of runoff, and sometimes is washed from streambanks during
high flows--which may themselves be higher and more frequent because of
silt-clogged channels. The bulk of it can be blamed on unsound land use.
This may be rural, based in the old use-her-up-and-move-along pioneer
outlook that has never died out among us despite wide understanding of
better ways of doing things. People in places still overgraze pastures
and clean-cut timber so that rain can get at the soil and eat it away,
and they still farm land too steep to stay in place without its
vegetative cover, or they plow even suitable rolling land in straight
rows up and down hill so that water and soil sluice away together down
the furrows when it rains. Despite a sharply effective three decades of
work and public education by the Soil Conservation Service and other
agencies, these old practices continue in some places and cause much
erosion.
[Illustration]
Also, increasingly, bad land use involves the ways in which great
machines adapt the landscape to hundreds of sophisticated purposes. The
massive eatings of powered blades and scoops to get at coal and other
minerals on the steep slopes of the North Branch watershed and
elsewhere, add heavily to sedimentation. So do broad rights-of-way
gashed out of the countryside and left bare under storms in the months
before highway construction is done, and secondary roads that even when
finished may be left for years or forever with denuded clay shoulders
and ditches and banks that wash with every rain. And so, most
particularly, do the great polygons of rolling land around the Basin's
town and cities that are stripped naked by bulldozers and left sitting
in that condition for long periods, while they await the erection of
buildings and blocks of homes. This is occurring throughout the Basin,
but most notably around Washington, where the highest erosion rates of
all are found. We will take a look at its details and the reasons for it
a little further along in this chapter when we examine the estuary's
situation.
Except for the acid parts of the North Branch, the upper Basin's waters
in most places, most of the time, can still serve the "practical"
purposes to which they are put--irrigation, industrial uses, municipal
supply after purification, and even the absorption and digestion of
effluents from adequate, well-run treatment plants. Most of the streams
are usually good to look at, especially in conjunction with the superb
rural landscapes against backgrounds of wooded mountains that are
characteristic. They furnish much pleasure to fishermen, hunters,
boatmen, swimmers, picnickers, and other folk, though in some places it
is an open question, as we have seen, whether or not contact with the
water is prudent. And almost everywhere, aging locals can recall a time
when their stream was a happier amenity than now--when it held more
fish, ran clearer over stones and gravel not coated with weeds and
green slime, did not have the smell it presently emanates, was colder
and more copious....
Their nostalgia probably does not play them false, even though
conditions in many places are better now than in the intermediate past,
after modern times had settled in, but before INCOPOT and the Soil
Conservation Service and such influences had begun to push for reform of
the casual, anciently human ways of doing things in which present human
populations can no longer afford to indulge themselves. Some of the
gains that have been made are being cancelled out by growth and new
types of pollution, however, and in general the flowing Potomac river
system is teetering at the brink of bad trouble. It needs help.
If the flowing upper Potomac had any lingering oxygen deficiency in its
lower stretches--though it seems usually not to--it would tend to
rectify the lack in its turbulent eighteen-miles descent across the Fall
Line, a superb natural "treatment plant." Normally it arrives at
Washington charged with oxygen, but does bring down with it the part of
its nutrient load that has not fertilized upstream weeds and algae,
periodic waves of bacterial concentration, and a great deal of debris
and silt in season.
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