Any unfortunate day now a set of new, higher railings will be added to the Duke Ellington Memorial Bridge, the bold, arched structure that carries Calvert Street across Rock Creek Park.

Sometime next year higher railings, as yet undesigned, will be part of a thoroughgoing rehabilitation of the elegant Taft Bridge carrying Connecticut Avenue over the valley.

The year after that, should the budgeting process proceed on schedule, railings of similar height will be added to the massive, stone-faced Massachusetts Avenue Bridge above the park.

The reason for the additions is simple: suicides. Since 1978, 33 persons have fatally hurled themselves from the Taft and Ellington bridges. The heights of these two bridges, each towering about 125 feet above the creek, park and roadways, make death a virtual certainty once a jump is made. These bridges, especially, have become, in the apt, grisly words used in suicide-prevention clinics, Washington's "suicide landmarks."

In the face of such statistics it may seem cruel to announce esthetic, symbolic and functional objections to the new railings (or, as they are called by suicide researchers, "protective hardware suicide deterrents"). Nonetheless, objections must be raised. Washington's beautiful bridges contribute greatly to the unique character of the capital city, and among these bridges the Taft and the Ellington rank extremely high.

The Taft, a soaring, five-arched masonry structure completed in 1907, was rightly "held up as an example for future bridge construction in the District of Columbia," Donald B. Myer tells us in his book "Bridges and the City of Washington." The Ellington, an equally elevating though simpler, three-arched span completed in 1935 after the design of noted architect Paul Cret, was conceived as "subordinate to the more exhibitionistic structure of its neighbor, the Taft," Myer observes.

To paraphrase architect Louis Kahn, these bridges "do what bridges are supposed to do" -- they powerfully express the basic connective, spanning functions of bridges -- and they do it in ways that are particularly suited to Washington. The Taft, with its open-spandrel central arches and handsome ornamental details (particularly the light stands with the open-winged eagles on top), makes a memorable entrance to or exit from the city's monumental core, with its classic revival theme. Ditto for the Ellington, with its limestone facing and stripped-down detailing. In each design the relationship of part to part -- of railing to parapet, parapet to pier, pier to arch, and so on -- was a matter of fine-tuned judgment.

As with buildings of similar nobility and age, adding important elements to these bridges should only be done, if at all, with the kind of care and consideration that went into the original designs.

One must credit the District government for trying. It did not decide simply to add standard, chain-link fence-type barriers to the Ellington Bridge (selected as first in line for the new railings because it is in good shape, while the others need more substantial repairs). The public works department came up with a picket fence-type design that, instead of replacing the curved handrail and concrete parapet of Cret's design, would be added to them.

The design was changed slightly -- spacing between the 3/4-inch-diameter picket bars was increased from four to six inches, and the arrowlike tops were removed -- at the request of the Commission of Fine Arts. The new fence will be painted a neutral gray (in subtle contrast to the soft green of the existing rail) and the bars will curve inward at the top to discourage climbing. Together, the parapet, handrail and fence will form a barrier 8 feet 3 inches high. The barrier will cost $160,000, 80 percent of which will come from the federal government.

This tacked-on fence, a significant addition to a great structure, doesn't come anywhere close to being the best possible design, which prompts the question: If we are going to build such barriers, should we not seek, perhaps by design competitions, the very best? The hope that "visually it goes away," expressed by Edward D. Stone Jr., a member of the Commission of Fine Arts, during the meeting on the Ellington fence, is perhaps supportable if one tries to visualize the massive bridge with its new railing from Rock Creek Park. But from close up -- from the point of view of a pedestrian or an automobile passenger crossing the bridge -- there is no way.

The views from these bridges, used by thousands of motorists and pedestrians each day, are treasured vistas that, besides being spectacular, emphasize one of the rare facts about this city's design -- in its very heart Washington has, almost literally, a primeval forest called Rock Creek Park. There is no use pretending that the views will be the same when obstructed by a course of jail cell-like bars.

And the precedent is symbolically disturbing: after the Ellington, the Taft; after the Taft, the Massachusetts Avenue; and after that, are the Klingle Valley, the Key, the Chain, the Buffalo, the Cabin John, the South Capitol Street -- among other bridges -- to follow? Is Washington to become the city of barred bridges? And if so, to what purpose?

There is no question that the barriers will deter suicides in a particular location, but there is pronounced disagreement about the effect on the city's overall suicide rate.

Dr. Herbert Modlin of the Menninger Foundation in Topeka, Kan., states that "the proposal for bridge barriers might reduce the incidence of suicidal leaps, but the probability is that it won't reduce the incidence of suicides in the District of Columbia by one iota."

By contrast, Dr. Richard Seidin of the Berkeley, Calif., Suicide Prevention and Crisis Center, has conducted a study of the lives of 515 people after they were restrained (over a period of 34 years) from jumping off the Golden Gate Bridge. The study shows that, while the incidence of suicide (or other violent deaths) among this group was greater than for the population as a whole, fully 90 percent remain alive or died from natural causes. In other words, Seidin has said, "There is justification for intervention or prevention."

Besides this fundamental disagreement, there are other questions that apparently have not been looked into with any great care. For instance, a good lawyer might argue that, by providing protection in one location, the District government would be fair game for damage suits after successful suicides in places without such protection. And it is conceivable that the money put into these fences might be better spent beefing up the city's person-to-person suicide programs. Would this not save more lives? To put the question another way, is the fence solution the easy way out, the one that, because so visible (and so easily financed), gives the feeling of having done something without having done much at all?

This clearly is a matter that deserves more public scrutiny than it has had so far. (The Commission of Fine Arts, after all, simply commented upon a given solution and not on whether the solution, in itself, is seriously flawed.) In all of this there is one certainty: Adding even the most beautifully designed barriers to our bridges will have profoundly negative long-term effects upon the civility of this city.