The dramatic and tragic accidents on Interstate 95 on Saturday in Old Lyme were yet another reminder that the stretch of highway through eastern Connecticut does not meet modern transportation needs, inviting chaos and gridlock.

While motor vehicle crashes can happen on any stretch of road, and police will long be sorting out exactly what happened in these recent accidents, there is no disagreement about the inadequacies of this stretch of highway.

At two lanes through much of the region, I-95 is too narrow to handle the heavy volume of traffic, which as the early morning accidents will attest, only eases up modestly even during off-peak times. Large tractor-trailers race along at high speeds chockablock with subcompact cars. Exit and entrance ramps are often too short and too tightly clustered, leaving drivers insufficient time to accelerate, merge or change lanes.

When accidents occur, as they too frequently do, the tight conditions leave on-coming drivers little opportunity for avoiding trouble, often resulting in multi-vehicle and severe crashes.

In addition, almost any accident will close portions of the narrow highway, causing traffic jams and sending drivers on to side roads ill equipped to handle the volume, gridlocking local communities.

One of the early morning accidents Saturday involved eight vehicles, including two tractor-trailers, leaving behind a mass of twisted wreckage, killing two and injuring several others. With accidents on both sides of I-95 around Exit 70, it closed the highway for hours.

Needed are a major redesign and at least an added lane in both directions. In all respects, it would be a monumental and expensive undertaking to obtain the land, carry out the construction and handle the traffic disruptions.

It is part of Gov. Dannel P. Malloy’s 30-year vision to rebuild and upgrade Connecticut’s transportation infrastructure. His administration has placed the cost of his total plan at $100 billion, a nice round figure and one with likely little connection to any reality. The recent reopening of a bridge spanning the Mill River in New Haven suggests how project costs can grow. Originally budgeted at $5 million, the bridge project ran $18 million over budget and several years behind schedule.

Connecticut has to figure this out, with money for the transportation overhaul placed in a dedicated fund. For economic, safety and sanity reasons, Connecticut cannot afford to do nothing.