SUMMERVILLE — Digging a wider flow for Sawmill Branch Canal might be the key to freeing the latest snarl stopping the long-stalled Berlin Myers Parkway completion.

Engineers trying to solve drainage concerns raised about the project’s last leg are looking at widening the canal in a stretch near Luden Drive, where the parkway’s leg would run alongside it, as well as options such as putting part of the parkway on pilings in places.

Surveyors were out last week surveying for a computer-modeling study. The results could get the 25-year-old construction project moving again.

Improving the canal “is one part of the mitigation effort that will enable the project to be permitted and ultimately constructed,” Pete Poore, S.C. Department of Transportation communications director, said in an email.

The parkway, a 6-mile bypass around the Summerville downtown, has been sought for nearly a half-century, but didn’t get started until 1987. Conceived as an emergency route over the railroad tracks through the heart of a small town, it has become in the interim a vital artery to handling the mass of commuter traffic through the now-booming bedroom community for Charleston.

Originally expected to take five years to complete, the parkway has run smack into delay after delay, frustrating the iconic mayor who pursued the namesake road for most of his 45 years in office.

It’s become grit in the teeth of Mayor Bill Collins, who was elected vowing to get it done after Myers stepped down in 2011.

In a State of the Town speech earlier this month, Collins touted a long list of successes such as new police cars and tourism gains such as the impending annexation of the Colonial Dorchester State Historic Site. Then he came to the “challenges.” Guess which one loomed?

“I am frustrated,” he conceded last week. “But I’m also optimistic, in the sense that I think we have all the stakeholders together (on what needs to be done). In almost a year and a half in office, I have learned that the wheels of government grind extraordinarily slowly.”

The first three miles of the parkway finally were completed in the late 1990s for about $14 million. The last three miles — now expected to cost more than $55 million — have been stymied by funding shortfalls, environmental groups’ wetlands concerns and, since Collins took office, federal concerns over drainage. Much of the parkway runs through the floodplain along the Sawmill Branch Canal. The canal is the major drainage for the town.

Donnie Dukes of Davis & Floyd, a project subcontractor, said the plan to fix drainage concerns is expected to be completed by the end of the summer.

Collins said that with new subdivisions now extending beyond the parkway’s planned end on U.S. Highway 17A west of town, completing the road “is critical to the town of Summerville. It is the single biggest piece of infrastructure we have to get built.”

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