An issue of growing urgency which Congress will have to face is funding of necessary repairs to the 25-year-old U.S. interstate highway system. The 43.000-mile network of roads need $55 billion to make necessary repairs to aging roadbeds and complete the remaining 1.575 miles of the system, according to a Congressional Budget Office report, Without new financing, repairs will fall further behind and ultimate completion of the system may be delayed at least until the mid-1990s. the report saidi Sharply-increasing costs have accentuated the condition. The price tag for building interstate roads has soared from $4 million a mile in 1959 to $20 million in 1979. Most of the remaining segments to be built are in urban areas where construction costs are especially high. The federal government cannot afford to allow the interstate system to deteriorate. We are dependent on the freeways. They have reshaped the lifestyle in which Americans live. work and shop. And they’ve influenced a major growth of suburbia and the services it requires. The system, of course. is vitally-important for national defense transportation. So how can Congress generate extra money for the interstate roads in a pinched economy? A 3-cent increase in the gasoline tax is one proposal being “kicked around” among lawmakers directly concerned with the problem. This would amount to a user-type fee, with the heavier users paying the larger part of the added tax. Other ideas may be thrown into the hopper. Direct funding by congressional appropriation seems a doubtful course in view of the tight federal budget and awesome deficit. One thing seems obvious: Action on the issue must not be delayed unduly, Segments of the road system already are beginning to need substantial repairs. We must protect our highway investment. To postpone improvements unnecessarily could turn a vital matter into a crisis.