The Nation\'s River

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In the broadening, slowing upper estuary, its sluggish currents confused
by the twice-daily surge and ebb of tides, these materials from above
are stirred in with an array of specifically metropolitan
pollutants--with more silt off of the outraged urban watershed, with
junk and debris of a thousand sorts, with decaying substances and
bacteria from many sources, and with vast new quantities of nitrogen and
phosphorus. The consequence is a weighty and sometimes spectacular
pollution problem directly adjacent to the proud national capital. It is
at its vivid and aromatic worst in summer, when the most Americans come
there fondly to view the city and the Potomac, and when locals who want
to boat and fish and swim and do the other things one does on water
would make most use of the river--indeed, do make use of it in spite of
everything.

Like the meek, the upper estuary inherits the earth, or at least that
part of the Basin's earth that is washed downriver as silt. There are
enough fine suspended sediment particles in the water of the
metropolitan river to make it drably opaque most of the time, even
during relatively dry spells, when heavy sand and gravel dredging helps
to keep it stirred up. As the current loses force and washes back and
forth with the tides, the particles settle out slowly into smothering,
continually renewed blankets on the bottom, and over two centuries have
accreted into great mudbanks and shoals. Channel dredging to maintain
navigation has been going on since the early 19th century, about 180,000
cubic yards being presently removed each year. The dumping of the
dredged materials on the marshes and long low shores has built up wide,
flat, new flood plain areas around the city over the years, including
the sites of Washington National Airport, Anacostia and Bolling Air
Fields, and East and West Potomac Parks.

Such channel dredging has little effect on the gradual shoaling of this
whole part of the river in general. Miles of formerly navigable water
downstream from Memorial Bridge are now only one to four feet deep and
useless for either pleasure or commercial craft. It has been estimated
that present rates of deposition will within fifty years fill in the
upper estuary completely to a mile or so below Alexandria, except for a
river channel. The same process is at work in the tributary creek-bays
that give onto the estuary, some of which have silted so heavily since
Colonial Days that formerly thriving ports--among them Bladensburg,
Dumfries, and Port Tobacco--are now distant from the water.

The bulk of estuarial silt comes down the main river from the upper
Basin. But a heavy increment is added in the metropolitan area. Modern
mechanized development of the city's hilly environs on a huge scale,
continuing year by year with few thoughtful rules to guide it
heretofore, has brought about erosion that on individual patches of
bared land may reach a temporary rate of 50,000 tons per square mile per
year, and even average rates in this area are far in excess of anything
else in the Basin.

We had to examine the reasons for this rather closely last year in a
study of Rock Creek's ailments, whose findings we published in a report
called _The Creek and the City_. This much-admired metropolitan stream
has been relatively well protected, with the parks along its wooded
valley and an upper watershed that until quite recently remained
essentially rural. But as development has proceeded in standard and
careless ways--the wholesale stripping and scarification of big tracts
of rolling, fine-textured land, the long naked wait for development--the
creek has come to be muddy and ugly almost all the time and has been
spewing an estimated 100,000 tons of sediment a year into the estuary,
with frequent floods.

[Illustration]

[Illustration]

To help save the creek and its parks and to stimulate a better kind of
development of the rest of its basin, citizens formed a watershed
association under Soil Conservation Service auspices and brought about
the construction of two small upstream reservoirs to control
flooding--with results noted in the preceding chapter--and to collect
silt. They sought to promote better land use as well, for the
reservoirs' effectiveness is obviously dependent on their not filling up
quickly with an excess of sediment. Better land use around a city
depends on zoning and other legal devices to regulate the density and
distribution of construction, and on controls over the way land is
shaped, and a sharp conflict developed between the watershed's defenders
and the Council of Montgomery County, Maryland, in office at that time,
whose rezonings in favor of standard massive suburbanization and whose
failure to enact sediment-control ordinances threatened the whole
effort. Rock Creek has many friends, and their subsequent fight for its
salvation has had good effect, though much remains to be done.

[Illustration]

However, Rock Creek is only one of many metropolitan streams that need
protection, both for their own sake and for that of the estuary. Some
are getting it--in the preceding chapter we noted the happy example of
Pohick Creek in Virginia, where whole watershed planning is being
accomplished almost from scratch, before development. But many more are
being ruined by the steady advance of standard urban sprawl.

Thus the main cause of urban silt is faulty or nonexistent or powerless
land planning, and the problem merges with the whole question of
landscape preservation. The ecological principles involved in good
practical land planning--the distribution of uses based on what land and
water can take without being degraded and causing silt, flooding, and
downstream pollution--are the same basic principles that lead to scenic
beauty and a decent human environment. This is a subject we will explore
in more detail when we arrive at considering the landscape as a whole,
but for now it may be worthwhile to note that insofar as urban erosion
and silt stem from decisions of political agencies inclined to subjugate
well-known good land use principles to speculative pressures,
expediency, and other things, their origin is political and economic.

Organic materials are pervasive enough in the upper estuary that during
periods of even normal flow their decay pulls oxygen levels down. Under
usual conditions this B.O.D. grows worse and worse downstream and
reaches a peak in the neighborhood of Mount Vernon, though its effects
continue to be felt below. Fish kills among the rugged resident species
that predominate in these reaches of the river are not uncommon, the
shoreline windrows of deceased carp and perch periodically adding their
essence to what metropolitans have come to accept as the Potomac's
normal summer smell. And along with the organic materials are heavy
concentrations of bacteria.

The organic and bacterial load enters the estuary from many sources,
most of them local, for only a little of this material comes down from
the upper river. A significant amount of it issues from the network of
small urban watercourses like Rock Creek. Many of these were covered
over as storm sewers or troughed in concrete long ago, but they continue
to serve their age-old function of draining the lands they traverse,
even if through cast-iron gratings.

A good bit of the organic load in these tributaries consists of raw
human waste, incongruous and particularly obnoxious around a modern
city. The bulk of it is released in periodic surges when local
rainstorms overload the old-fashioned combined sewer systems of the
District of Columbia and Alexandria. In dry weather these systems send
both collected sanitary wastes and street drainage down to the cities'
respective treatment plants, but during storms when street drainage is
heavy the sewers' capacity is exceeded and overflow gates gush mixed
stormwater and sewage out into the streams, which carry it to the
estuary.

In the suburbs, more modern separate storm and sanitary sewers are the
rule, but they too have some problems of a kind we noted in relation to
the upper river. Investigations on Rock Creek revealed steady dribbles
of raw sewage entering the creek or its tributaries from a large number
of storm-sewer outfalls and other places. Partly these flow from
malfunctioning individual septic systems in outlying areas,
surreptitious connections of house sanitary sewers to the storm system,
breaks and leaks in sanitary sewers, and such things. Partly too they
seem to come from the fact that some sanitary sewers are having to carry
more sewage than they were designed to handle, so that their overflow
valves leak more or less constantly into the storm sewer system. The
capacity of sewage collection systems is related to planning. If a pipe
is laid down to a fringe area where county zoning maps indicate only
limited development is going to be permitted, its size is gauged to that
kind of development. But if the zoning is changed later and three times
as many houses are hooked up to the line as were originally envisioned,
trouble results. Rock Creek is heavily affected by such sewage, and the
chances are that the situation is much worse on many other urban
drainways, for their longstanding degradation or sheer disappearance
from view has lost them the alert defenders who watch over Rock Creek in
its pleasant valley.

Out of the storm sewers whether combined or separate, off of the roads
and streambanks and hillsides, down the urban tributaries or directly
overland into the estuary, comes still another big jolt of organic and
bacterial pollution every time there is a heavy rain. This is surface
runoff, the washings of the street and parks and sidewalks and rooftops.
Besides debris, it contains vast hordes of bacteria and many kinds of
organic oxygen-demanding substances, of which animal droppings are only
one easily definable example. Around a city the size of the Washington
metropolis, this runoff would constitute a worrisome pollution problem
even if the matter of sanitary wastes were thoroughly in control.

[Illustration]

Ships and large boats in the estuary, in accordance with an
unfortunately persistent nautical tradition, generally discharge toilet
wastes and garbage directly into the water on which they float. Some of
these are coastal or transoceanic vessels, both commercial and naval.
Many more belong to the fleet of pleasure boats which have been
increasing at Washington despite the water's unpleasant state to which
they add their bit, degrading the element that is supposed to provide
the enjoyment for which the boats were built. It is not a problem
limited to the Potomac estuary, but widespread these days and the focus
of much concern among public health and pollution control authorities,
conservationists, and the boat and marina industries themselves.

Around the various marinas to be found along metropolitan
shores--several of them Federally owned--sanitary facilities are
generally skimpy, and no regulations govern the discharge of wastes from
boats. Since individual marinas may berth as many as 600 or 700 craft, a
great many of them in daily use during the recreation season and some
inhabited as dwellings the year round, summer conditions that frequently
prevail around these places are not to be described in polite terms.

Less visible at the point of origin though not in its ultimate effects
is the huge organic load that comes to the estuary in the effluent of
local sewage treatment plants, estimated at possibly 300 to 350 million
gallons per day. There are many smaller plants strung out down both
shores of the upper estuary, but four larger ones handle the bulk of
metropolitan sewage. Of these, three--the main plant at Blue Plains in
the District, the Alexandria plant, and the Fairfax County Westgate
plant--furnish secondary treatment, and the fourth, the Arlington County
plant on Four Mile Run, is on the verge of putting new secondary
facilities into operation.

Yet the same problem of plant operation that exists in the upper Basin
also rears its head here. A casual boat ride down the shoreline with a
few excursions up tributary creek-mouths demonstrates that many of the
smaller plants, including a number of Federal ones, are emitting a very
low quality of effluent, and this is borne out by sanitary surveys. The
proliferation of such small plants around cities and elsewhere is a
headache to sanitary authorities, for their very size and numbers create
a probability of trouble. Much effort is going into eliminating them and
channeling the wastes they receive into the larger plants.

But the large plants themselves at this point are a much bigger part of
the problem; on the basis of sheer volume, their contribution to
estuarial pollution dwarfs all others. The Blue Plains plant is by far
the largest of the four, handling wastes from about 1.4 million people
in Washington and outlying areas on both sides of the river. By the
terms of a conference convened in 1957 by the Public Health Service to
investigate the sanitary state of the Potomac at Washington, the
District committed itself to maintain 80% efficiency of treatment at
this plant, which was then brand new. Last year, ten years afterward,
the most generous recent calculation of the efficiency there was 62%,
and some qualified observers expressed a conviction that Blue Plains had
never consistently functioned at much over 50%--in other words, it had
been returning to the estuary unassimilated organic materials equivalent
to the raw discharges of a population of roughly 500,000 to 700,000
people each day. Nor do these figures include a great deal of sludge
that has been flushed on into the river when digesters have failed to
function properly, or the plant's frequently inadequate use of
chlorination against bacterial pollution and odors. Since the same 1957
conference required of the other metropolitan jurisdictions only that
they do equally as well as the main plant in quality of treatment, they
have clearly not been obligated to superhuman effort.

[Illustration]

Criticism of Blue Plains is in part criticism of ourselves. Because of
the distinctive relationship between the District and the Federal
Government, the District's treatment plant is in a sense a Federal
installation, funded through Congress and with more direct links to
Federal water quality agencies than any other big municipal plant in the
country. The number of people the plant serves has, of course, increased
greatly in the past ten years. It may have been, as has been claimed,
somewhat underdesigned to begin with, and it undoubtedly needs expansion
now. Yet a rather substantial improvement in the quality of treatment
there in quite recent months, mainly under the stimulus of this planning
effort and the present surge of interest in the Potomac, indicates that
had emphasis on low operating costs been subjugated to pride in
results, the present plant could long ago have been made to function
reasonably well and the estuary would have had to cope with a much
lighter load of wastes.

The truly spectacular manifestation of pollution in the metropolitan
Potomac is the periodic growth of algae there in summertime. When
conditions are right--when sun, summer temperatures, low inflows from
the river above, and a heavy concentration of nitrate and phosphate
nutrients all combine to make of the upper estuary one vast inspired
pool of fertility--the whole surface of the river may be covered with a
thick bright emerald mat, and boats that pass at speed leave wakes of
green instead of white. The infestation may extend downstream for thirty
or forty miles, in various degrees of concentration, and even if the
water were bacterially safe this "bloom," as it is called, would
prohibit its recreational use by anyone without a strong stomach. It
further disrupts aquatic life balances, and periodically dies and decays
aromatically, setting off whole new cycles of oxygen depletion, fish
kills, stink, and fertilization.

The problem is one of fertility, of course, and stems from the huge
quantities of nitrogen and phosphorus perennially present in the water.
Some of this comes down from the upper river--where, as we noted, much
of it derives from land runoff--but by far the greatest part of it
originates at the metropolis and enters the river through the effluent
of waste treatment plants. Efficiency of operation has hardly anything
to do with it, for even the best standard treatment has little effect on
nutrients.

Eutrophication is the scientific name of this kind of overenrichment. It
is occurring in many places, Lake Erie being the best-known single
example in this country. Though its causes are mainly known, the process
itself is still not fully understood, particularly in regard to the
function of nitrogen and the way it works. But the other key element,
phosphorus, has been more amenable to study and to possible action. It
occurs in body wastes, in artificial fertilizers, as a by-product of
natural decay, and very notably in detergents. Some eight tons of it are
released into the estuary each day from the treatment plants in addition
to the undetermined but much smaller amounts arriving from upriver, and
the usual overall accumulation is enough to make the river's phosphorus
content exceed that considered desirable all the way from Theodore
Roosevelt Island to Quantico, Virginia, and below, which represents the
general extent of the summertime "blooms."

Dilapidation begets disrespect, and the abused and often repellent
waters of the upper estuary are undoubtedly subjected to much additional
miscellaneous pollution by people who believe perhaps that a little more
cannot possibly matter. Again, Federal or Federally connected
institutions have not been setting the best possible example, and there
are many of them around the capital city. Unwarranted waste discharges
of one kind or another have been traced to most of the military
installations fronting the river, to military hospitals, to government
heating plants, to the National Zoo, to National Parks, and to similar
Federal sources including the marinas already mentioned. In most cases,
measures are now being taken to eliminate these discharges, but it is a
commentary on the complexity and difficulty of the whole task of dealing
with pollution that at the level of government where real concern with
the problem has been acute for a decade or more, and furthermore at and
around the very seat of that government, such practices should have
persisted this long.

[Illustration]

[Illustration]

Junk and debris of all descriptions infest the metropolitan river,
floating about, washing onto the shores, poking up stolidly here and
there out of mudflats. Most items in a dreary inventory that might be
compiled would turn out to be something that was discarded somewhere it
didn't belong by someone who did not want to go to the trouble to put it
where it did belong. Therefore, the main source is undoubtedly simple
disregard for the sensibilities and rights of others, multiplied and
complicated by the immense number of people in the metropolis and the
wide territory they occupy. In our study of Rock Creek last year, some
powerful subsidiary reasons for the prevalence of debris turned up also,
ranging to streetcleaning methods and the inconvenient hours kept by
some public dumps where citizens have to carry their larger trash.
Metropolitan problems are seldom simple, and many of them in one way or
another manage to inflict a part of their complexity on the river at the
national capital, which is sad but possibly appropriate in a time like
the present.

The lower estuary

Downriver from the main effects of the metropolitan complexities, the
widening brackish and salt portions of the Potomac estuary form a
generally healthy body of water, though changes loom as the metropolis
moves inexorably outward from its center and as hitherto remote
Tidewater areas are brought more and more under the influence of modern
ways of being. Localized problems of pollution point to general dangers
that will certainly materialize unless safeguards are set up in time,
for estuaries are delicate, immensely productive, and still somewhat
mysterious aquatic environments that have been and still are too much
taken for granted.

[Illustration]

[Illustration]

Rapid human intrusion on estuaries during the past twenty years has
been making apparent their phenomenal value in a natural condition.
Vulnerable, attractive to diverse interests that work their beds for
sand and gravel and fill in their marshes for development and casually
pollute them, they have recently been called America's most endangered
natural habitat. They are almost unbelievably fertile places, with
involved biological cycles that can convert the fertility into usable
food at rates per acre far exceeding those of the finest farm land; in
terms of money, one recent set of experiments indicates the possibility
of attaining an annual shellfish production on tended beds worth over
$26,000 an acre.

Furthermore, aside from the direct harvest of this wealth from estuaries
each year by commercial and sport fishermen, these in-between waters
make an indispensable contribution to the entire Atlantic coastal
fishery, an industry worth a billion dollars a year. The reason for this
is that at least 70 percent of coastal fishes spend some essential part
of their life cycle within an estuary--spawning there, or passing
through on their way to spawn in running fresh streams, or moving in as
fry from the rivers or the open sea to find a "nursery" in one of the
varied estuarine habitats--bays, marshes, sandy shorelines, mudflats,
tidal creeks, or weed beds.

The oysters from the famous beds in the Saint Mary's River off of the
lower Potomac are mainly condemned as unfit for consumption because of
local sewage pollution, and these beds are not the only unfit ones, for
towns and resorts in the region have been growing and sanitary
facilities have not been keeping pace. Already some arms of the superb
natural harbors formed by the tributary creeks are noxious with
discharges from boats at big marinas, and gravel dredging is stirring up
silt to smother bottom life, including shellfish. As Tidewater
agriculture revives and modernizes, pesticides and artificial
fertilizers are coming to be as much a part of the scene there as in
other farming regions, and may be expected to influence the estuary--in
fact, they undoubtedly already are doing so in subtle ways with effects
not yet apparent.

Yet most of this part of the river is still beautiful and continues to
yield good harvests of seafood. The Potomac River Fisheries Commission
has been alert to obvious dangers and has moved against them where its
powers have permitted, and natives of the area are increasingly alert in
protecting the estuary. Many of them depend on it for a living, most are
oriented toward it for their pleasures, and until lately a good many of
them counted on it for transportation. In a number of different ways, it
matters in their lives. And that fact offers some hope for the future,
especially if it is fostered and strengthened by overall protective
measures.

Techniques for cleaning up

Two main general approaches to water quality improvement exist:
treatment of pollution at its source or occasionally after it has
entered a stream, and augmentation of the stream's flow to help it
assimilate loads of waste beyond its natural capacity. A third
possibility in certain situations is the diversion of wastes out of a
stream's drainage entirely. In practice, these methods can be varied and
combined in any number of ways to fit a need.

To take the last one first, diversion of whole wastes as received from
their sources is a total and dramatic means of coping with a pollution
problem stemming from collectable wastes, but it often has
disadvantages. One of these, of course, is the possibility that the
pollution problem may be simply transplanted elsewhere--that the water
in which the wastes eventually end up will suffer. Another is loss of
water from the stream system. If, as is usual, a town gets its water out
of the local river or a tributary and does not give it back after
use--preferably well cleaned up--other users downstream are not going to
have as much water available to them, and the essential processes and
ecology of the river itself may suffer.

The only place such wholesale diversion of wastes has been seriously
considered in the Potomac Basin is at metropolitan Washington, whose
sewage could feasibly be piped across Chesapeake Bay and the Delmarva
peninsula and well out into the Atlantic--possibly, as has been
suggested, in combination with sewage from Baltimore. It would be a
permanent means of disposal, but very expensive in terms of both
investment and operating costs. Furthermore, though in the estuary no
downstream users would suffer a loss of water supply, the water content
in metropolitan sewage has at times risen as high as 80 percent of the
flow of the river above the upstream intakes. The effects of such a
subtraction of fresh water on the estuary itself--changes in flow, and
in the penetration of salt water upriver, with an inevitable alteration
in valuable fisheries and the whole balance of aquatic life established
through millennia--could easily turn out to be disastrous.

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