So Washington's traffic congestion now is front-page news [Dec. 16], although no explicit reference is made to the underlying cause. The problem is not too many cars and too few roads; it is too few opinion makers willing to admit the obvious.

The fattest sacred cow in our land is population growth. It is the clear cause of countless daily problems, including traffic jams, but it is seldom mentioned by news and editorial writers.

When a hole appeared in the ozone layer, we banned chlorofluorocarbons. When evidence of global warming emerged, we started looking for ways to reduce emissions of greenhouse gases. But our birth and immigration rates are treated as though they were sovereign acts of God, rather than the direct results of decisions by parents, legislators and regional planners.

DARYL P. DOMNING

Washington

The front-page article on the growing traffic bottlenecks on area freeways points to a need for innovative solutions.

A bottleneck on the Beltway can reduce traffic flow in rush hours from 8,000 vehicles per hour to as few as 6,000 vehicles.

This lost capacity can be recovered by separating the four lanes into two sections: (1) two electronically tolled express lanes, where tolls are set to limit traffic to the free-flowing maximum of about 4,000 vehicles per hour, and (2) two free lanes. This arrangement would allow an extra 1,000 vehicles through each hour, reducing overall delays.

Toll revenues from those choosing to use the express lanes could be used to compensate those who choose the free lanes. Travelers in the free lanes would need electronic toll tags, so that their use of free lanes could be recorded and their accounts credited. They could use any credits as toll payments on days when they choose to use the express lanes, or they could take cash payments periodically.

Travelers then would have a choice--either be stuck in traffic and be compensated, or zip along without delays and pay for the premium service.

PATRICK DeCORLA-SOUZA

Alexandria

Why is The Post so insistent that Virginia taxpayers throw their money away on a useless and expensive road-widening project in Arlington County [editorial, Dec. 15]? Traffic congestion may be "horrendous" on the Arlington stretch of I-66 during rush hour, but low-cost measures--more car-pooling incentives, express bus service, rail-station parking--haven't been tried and may provide relief. In any case, adding extra lanes will just increase traffic-related pollution and waste money needed for projects that can ease congestion.

Representatives of Northern Virginia jurisdictions recently issued a revised list of the new transportation projects they consider of highest priority for completion during the next 20 years ["Transit Wish List," Metro, Dec. 15]. It does not include widening I-66 in Arlington. What is emphasized is new rail transit facilities, especially an extension from Falls Church to Tysons Corner and Dulles Airport.

As the Council of Governments observed in its overview of regional congestion, this area "offers a sobering lesson, because it shows traffic slowdowns materializing even on roads that recently have been widened." I-95 and I-270 are recent local examples of futile lane-widening projects.

Adding an extra lane to I-66 in Arlington would cost $100 million or more. Why not spend the money instead on the high-priority transportation projects that really can help solve congestion problems, are desperately short of funding and are recommended by a strong bipartisan consensus of local leaders?

M. C. BRAGDON

Arlington