I can keep quiet no longer. I tried to maintain an open mind, but after observing the construction to widen the Beltway between the Rockville Pike and Georgia Avenue for a couple of months, I am afraid that my initial misgivings about the project were well founded.

As I expected, even though no lanes have been closed off, the lack of shoulders, intimidating concrete barriers or simply "something going on" have all contributed to daily slowdowns during rush hour. In the pre-construction days of late spring, traffic backups in this area were sufficiently severe to force me into using off-Beltway alternate routes once a week, at most. Now I make such detours three or four times a week. The construction has added an average of 10 to 15 minutes per day to my commuting. That may not sound like much, but over the predicted life span of the project, it adds up to about two extra 40-hour weeks behind the wheel per year.

The state of Maryland would like us to believe that we will save time in the long run, after the construction is completed. I agree that traffic flow will improve upon completion of the project -- but only back to the pre-construction pace. Fifteen years of observing drivers' behavior while commuting on this portion of the Beltway has convinced me that the problem with the infamous Rock Creek Park "roller coaster" is not a paucity of lanes so much as an abundance of curves. Apparently the state abandoned plans to straighten as well as widen this part of the Beltway. The state should have applied the old axiom: If you can't do the job right, don't do it at all. JOHN H. WITTMANN Lanham