In terms of the overall good of the people of the metropolis and the Basin and the country, the water situation at Washington now and during the near future hardly bears a desperate enough aspect to warrant the sacrifice of much of the main flowing river to a reservoir which, like the freshwater estuary, could not be meshed with upstream needs but would serve only the urban areas at and below the Fall Line. Conceivably at some future time, if technology should renege on its promise to bring forth good new alternatives, and population pressures continue to grow, the city may badly need a reservoir there. It is a uniquely valuable site. For that reason, we repeat our Interim proposal that the reservoir site, minimally defined, be preserved against the mass encroachment with which it is imminently threatened, and be utilized principally as part of a major park complex protecting the river and its shores. To defer irreversible decisions and to leave them as much as possible to future generations whose conditions of life and desires we cannot predict with accuracy, can be a principal way of maintaining freedom of choice. In the category of reservoirs, at the other end of the spectrum are the comparatively small headwater dams that the Soil Conservation Service has been designing and supervising for three decades in authorized watersheds throughout the country. These structures can serve several functions and can furnish for small watershed areas and small centers of population many of the benefits that the Corps of Engineers and Bureau of Reclamation dams furnish for large areas. On their own scale, they are vulnerable to some of the same objections that are aimed at large reservoirs. But the scale is smaller; they tend to be less imposing and pre-emptive of good land than big river dams, "catch the water where it falls" to hold it for local use and to alleviate local flooding, and are backed up by erosion control practices in a program that has proved to be one of the best available stimulants to good land use. For these reasons they have appeal for many rural people and conservationists. * * * * * However, the conclusion which some of their supporters have reached is that if only enough of the small dams could be built throughout the headwater areas of a river basin, they would eliminate the need for most other forms of water management, leveling out flood and drought flows and holding a great aggregate amount of water on tap for use anywhere down the line. At times in the past, the controversy between supporters of big dams and supporters of little dams achieved the proportions of a bloodless war, but after a good many years of testing and observation it is now generally agreed by hydrologists that both have their place and that the most appropriate focus for the small dams' functioning is local.