The list of objections could be extended--and often is by objectors--to a point of pettiness. Nevertheless, the main doubts are gaining much acceptance and are imperatively having to be taken into account more and more these days, as new elements of water technology and philosophy--some of them mentioned earlier in this chapter, others to emerge in subsequent discussions--come closer to full feasibility and become a part of general human knowledge. Delay in building reservoirs until it is certain they are needed is on the verge of becoming a respectable element in planning, and in the future dams may well become merely one of many ways to guarantee water and handle it. At least some water authorities, though certainly not all, have voiced the opinion that most present reservoirs will some day serve primarily for recreation, if emerging new principles of water supply, water quality improvement, flood protection, power generation, and such things attain general use. That day, however, has not yet dawned, nor is the interim before its arrival calculable. It is necessary to face present reality with present tools, and the reality at the Washington metropolis and elsewhere in the Basin is that a good deal of water is going to be needed rather soon, and that no reasonably economic alternatives with any clear esthetic and ecological advantage over reservoirs are presently available to furnish it. Nor, if planners and designers are aware of the whole set of problems, do reservoirs necessarily have to be weighty in their impact on the natural scene and the public interest. The quantities of stored water needed for the Basin's near future are relatively modest in comparison to potential supplies, and a multitude of good reservoir sites exist to be chosen from. There is no reason why, with present knowledge, a minimum of necessary reservoirs cannot be planned and designed for a maximum of beauty and pleasure. It is a notable fact that a very large number of Americans prefer boating and fishing and other aquatic sports on reservoirs to any other form of recreation, and another notable fact that in the upper Potomac Basin there are very few places where even small numbers of Americans can thus indulge themselves at present.