Yet in the Potomac Basin as a whole the threat so far is mainly still a threat, not a reality. Where men's employment of the land has been reasonable, as it has in the Great Valley almost from the start, the land not only remains useful and pleasant but has a specific traditional beauty dependent on man's presence. Where new comprehension of the processes of destruction has been attained and shared, as in soil conservation and forestry and such fields, much damage done in the past has been repaired. Most of the Potomac river system's flowing waters are unnaturally polluted to one degree or another, but only in spots does the pollution even approach the sort of poisonous hopelessness to be found along some more heavily populated and industrialized American rivers, and on the Potomac its spread is already being slowed. Water shortages loom, but have not yet seriously materialized. Floods threaten, but only at certain definable spots. Human beings boom outward from the Washington metropolis and the other centers of population in search of a fuller life, and the consumptive sprawl and sameness of the communities built to receive them often deny it to them. But in modern terms there are not really enormous numbers of them yet, and for their pleasure and fulfillment a great deal of varied and handsome and historic landscape has been more or less preserved, by design or happy accident. [Illustration: Proposed Water Resource Development 1. Sixes Bridge 2. Sideling Hill 3. Town Creek 4. Little Cacapon 5. North Mountain 6. Verona (Staunton) ] [Illustration: North Mountain] [Illustration: Town Creek] The Potomac Basin, in other words, is still generally a wholesome place two-thirds of the way through the 20th century. If it gets the protection it deserves, and is developed thoughtfully and decently to meet men's demands upon its resources, it can stay a wholesome place into the indefinite future. * * * * * Water pollution was the first Basinwide problem to make itself thoroughly evident, and the need to deal with it led to the first Basinwide activities besides studies. Soil conservation practices for sediment control were instituted in the 1930's, and in 1940 the Interstate Commission on the Potomac River Basin, often called INCOPOT, was formed by compact among the four Basin States and the District of Columbia, with the formal permission of Congress. INCOPOT's powers are only advisory in relation to State and community action against pollution, and it has never been generously financed. But during the quarter-century of its existence it has developed a wise combination of investigation, persuasion, and public education to fight this problem, with the result that on the Potomac conditions have in some ways actually improved during a period of wars and booms and haphazard urban expansion when many other rivers were headed straight down to stinking corruption.