The Post asked editorially last Monday: "Does UDC need a downtown campus?" The evidence from almost a year of careful study by a committee of the University of the District of Columbia board of trustees and a joint university-city administrative committee appointed by the mayor last March answers the question with a firm "yes." Not all of the evidence of that study was available to the writer of the editorial.

UDC is not asking for "another" campus. The university already has a downtown campus of sorts--405,655 square feet of leased space in nine buildings scattered around the downtown area. The university's annual lease cost for this space is $2,917,345.

The university is not seeking additional space for future enrollments. The overriding need is to pull together those existing UDC elements in downtown leased space--mainly the colleges of business and education--at one site and avoid costly lease expenses that are sure to continue to rise.

For instance, the annual cost of our most recently renegotiated lease on a facility housing a baccalaureate science program jumped approximately 300 percent, from $5.89 per square foot to $17.21. It is estimated that the university's annual average cost of leasing over a long term will be $7.2 million.

The mayor's administrative committee studied a range of options before recommending the imaginative plan now proposed: to allow a private developer to lease half of the city- owned land at Mount Vernon Square in exchange for building a downtown campus complex on the other half of the site. The long-range benefits to the city, the university and D.C. taxpayers would be property tax revenue from the developer-operated building, the avoidance of university lease costs, greater efficiency and flexibility for the university's downtown programs and--perhaps most important to the city--retention of a key property site that is certain to appreciate in value.

The plan confronts the issue of inflation head-on. Admittedly, the city could make a short-term gain through outright sale of the property. The mayor's administrative committee estimated the present value of the property at $64 million (318,000 square feet at $200 per square foot).

However, the long-term benefits of the proposed use of the Mount Vernon Square property are more fiscally prudent and provide maximum protection against further inflation. In addition to saving the $7.2 million in annual average leasing costs, the D.C. Department of General Services estimates that the city would gain $3.6 million annually in property tax revenues over a long-term lease period. At the end of the lease term, the developed property would revert to the city for whatever use deemed appropriate at that time.

Over the life of a 40-year lease, for example, the savings on university lease costs would total $288 million and the property tax revenue would add up to $144 million. Clearly, the city's plan for the use of the Mount Vernon Square property is fiscally sound in the long range.

The university's need for additional facilities is tied directly to current programmatic demands. As The Post's editorial pointed out, the vacant land next to the Van Ness campus is owned by the State Department. Even a cursory inspection of the Van Ness campus facilities would indicate that faculty and students are already teaching and learning in less than adequate space. The limited area for additional building at the Van Ness campus is planned to accommodate programs of the colleges of liberal and fine arts and life sciences, which were forced to remain downtown when other related programs of the two colleges were moved to Van Ness last summer.

The District government's request for a proposal for the use of the Mount Vernon Square property is a creative resolution of a problem critical to the future development of the university, one that Mayor Barry has worked hard with us to solve. The board of trustees welcomes public examination of the plan and its accompanying fiscal benefits to the city.