FUTURE SHOCK HAS COME to Harvard Square.

A monument to Camelot--the impending John F. Kennedy Library Center--is transforming the area. Already, a shopping mall is rising next to Holyoke Center, acrylics are replacing brick storefronts, rents are rising out of sight, and soil experts are boring into the Common and MBTA yard. And much more is coming.

By the time graduating seniors return for their fifth reunion, at least two highrise buildings will tower over the Square. Over a million tourists a year will be visiting the Kennedy Library on the 11-acre MBTA site across from Eliot and Kirkland Houses. Streets will have been rerouted to handle new floods of traffic. Coffeehouses and bookstores will have fled before an onslaught of hotels, tourist shops, and hamburger stands. Parking facilities will be swamped, and construction of an MBTA Redline extension, out to the Fresh Pond shopping center, will be underway.

Such changes will electrify the economy of the Harvard Square area. But a number of Cambridge residents, civic groups, and even businessmen are warning of a definite potential for catastrophe.

Francis H. Duehay '55, dean of Admissions and Studies in the Graduate School of Education, local resident, and City Council member, thinks the Kennedy Center "will almost certainly increase congestion to a barbaric extent."

Nancy Brigham, a member of the Cambridge Tenants Organizing Committee, sees the Center leading to rent hikes which will drive low and middle income residents out from surrounding areas.

Cyrus Harvey, owner of the Harvard Square Theater and a leading force behind a local group called Planning for People, predicts "total disaster" if nearby neighborhoods aren't protected from swarms of visitors and if the business district is not integrated with the Center.

Robert Bowyer, head of Cambridge's Department of Planning and Development, worries that the character of the Square may be corrupted by the influx of tourists.

Of course, most recognize that the Kennedy Center--a complex including a library, archives, the Kennedy School of Government, and possible "related structures"--may prove to be the greatest blessing to the economic vitality of the Square in this century. But it doesn't assuage the fear that the ingredients of success may be ruined in the mixing, turning the Square into an ugly fusion of traffic jams, parking lots, and tickey-tac, thereby destroying the small stores and whatever remains of the Square's college-town atmosphere.

Changes have been expected ever since the trustees of the Kennedy Corporation--the group overseeing construction of the Center--announced their plan in the mid-sixties to move the Library onto the MBTA site. A year ago, the Cambridge Planning Office began assembling a seven-volume master plan to cope with the difficulties expected to arise.

Volumes I through V of the Plan are nearly done. They survey the success of previous planning efforts, planning philosophies, raw census data, traffic flow, and the visual environment of the Square.

Volumes VI and VII, concerned with the issues peculiar to Harvard Square and the actual plan itself, will not be ready until September. But through conversations with Planning Department officials, the following proposals seem likely to emerge in some form:

*Extension of the MBTA subway line out to Fresh Pond or another point near the Alewife Brook Parkway. Traffic studies--largely complete--show that most Mass Ave traffic has at least one endpoint in Cambridge, making extended rapid transit feasible.

*Elimination of some streets and redirection of others. Surprisingly, the planners say, traffic can often be handled better on a small number of streets because the number of intersections and junctions declines. Planning officials also believe that introducing one-way streets where two-way streets now stand would help smooth traffic flow.

*Improvement of parking facilities. Parking for the expected avalanche of tourists will be provided largely by a lot, possibly underground, on the Library site. A $225,000 study is also currently in progress to explore the desirability of an underground garage at the Cambridge Common.