pal 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