There is much to like in the transportation reform bill approved last week by the state Senate: An end to the irredeemably flawed Turnpike Authority; a rollback of excessive employee and retiree benefits at the MBTA and other agencies; a merger that should provide increased accountability and efficiency.

There is much to like in the transportation reform bill approved last week by the state Senate: An end to the irredeemably flawed Turnpike Authority; a rollback of excessive employee and retiree benefits at the MBTA and other agencies; a merger that should provide increased accountability and efficiency.

The bill barely nibbles at the state's largest transportation problems: Billions in Big Dig debt that, without action, will force huge increases in Mass. Pike tolls and MBTA fares, and a projected 20-year shortfall of up to $19 billion to maintain current roads, rails and bridges. But lawmakers promised reform before revenue, and this is the reform. Legislative leaders say they'll take up revenue, which will include debate on raising the gas tax, by July 1.

Gov. Deval Patrick and top lawmakers have stressed "regional equity" in transportation reform, which should mean protecting Pike tollpayers from being saddled with an unfair burden. We have good reason to study the bill's details carefully. The last time Massachusetts' transportation finances were "reformed," an outsized portion of Big Dig costs was dumped on Pike tollpayers.

The Senate bill includes some protection, thanks to the efforts of Sen. Karen Spilka, D-Ashland. The merged agency's governing board will include a member from the Pike corridor between Rte. 128 and I-495. Refinanced bonds are to be backed by statewide revenues, not tolls. Toll revenue is limited to 15 percent of all funding dedicated to transportation, which is intended to prevent the Pike from being used as a cash cow for all the state's transportation needs.

There are plenty of details that must be sorted through, and watched carefully, as the bill now goes to the House. There is the question of future toll hikes. As long as just one of the state's five major interstate highways have tollbooths, tollpayers' champions on the merged agency's governing board will be outnumbered.

Then there's the matter of some $310 million in cash reserves held by the two sections of the Pike. Depending on how the refinancing is structured, that cash may be freed up - and officials will be tempted to spend it on everything from subsidizing the MBTA to filling potholes on Cape Cod. But that money came out of the pockets of Pike tollpayers, and it should be dedicated to toll relief.

Another pot of cash will appear if Pike officials accept the bids now being submitted for the sale of Pike service plazas. That money should also be returned to the tollpayers who built the Pike.

This isn't the bill we would have written. We'd prefer the tolls on the western Pike come down as scheduled in 2017, if not sooner. We'd rather see tolls collected east of Route 128 be segregated from other transportation funds and limited to maintaining the highway on which they were collected.

Legislators have been working hard on these issues for months, in the face of a political culture that has shortchanged or ignored this region for decades. There's much work still to do. House members must pin down, improve or at least protect, the promises of regional equity in the Senate bill. If they fail, drivers will be paying for it for many years to come.

The MetroWest Daily News