suffered to some extent, but the picture was not nearly so
dismal as it would have been if the river had not been helped out more
or less by accident. The source of this help was some 2000 gallons of
water per minute that the Merck plant at Elkton and the Dupont plant
near Waynesboro were releasing after having pumped it out of deep
aquifers and used it for cooling. If all sources of pollution had been
receiving adequate treatment, this minimal dilution might not have been
so badly needed to avoid the fish kills and algal stagnation and other
results that would have ensured without it. But "all sources" include
the problematic agricultural drainage, and for that matter the
definition of "adequate treatment" is going to have to go up and up in
our expansive future.

The sad situation of the smaller and much less industrialized Monocacy
in the same summer underscores the point. The Monocacy flows through
similar farming country and passes by a few towns. The largest of these
is Frederick, Maryland, for whose approximately 40,000 people the little
river furnishes water and a conduit to carry away the effluent from
their average-to-good secondary plant. At times during that dry summer
practically the entire flow of the river below Frederick consisted of
effluent, with effects on stream life, esthetics, and the general
surroundings that are not hard to imagine.

Another good example of a place where, under present conditions,
augmentation could sometimes be used beneficially is at Great Falls and
in the Potomac gorge below. Heavy public expenditure has protected the
shore in much of this neighborhood and provided pleasant recreation
areas whose main scenic focus is the violent magnificence of the river
in its plunge. But the magnificence becomes a rather drab joke in dry
summers when metropolitan withdrawals of water above that point shrink
the river to a semblance of normal flow.

[Illustration: Low Flow Augmentation]

The North Branch and some smaller Basin streams also need this same kind
of help and most will continue to need it even when the best
economically feasible treatment of all collectable wastes entering them
is ensured. It can be provided out of reservoirs, large or small, whose
need for other purposes as well will keep the cost of dilution within
reason. A future possibility, if research presently going on in the
Basin verifies it and shows ways of putting it to use, is to employ
ground water in the same