The Army Corps of Engineers said today that it won’t take as long or cost as much as expected to study the proposed deepening of the Charleston Harbor.

Officials also said if everything goes just right, the shipping channel could be deepened by five feet by 2020, four years ahead of previous estimates.

The federal permitting agency said the study would cost about $15 million and take 4 years or less to complete. Previous estimates were $20 million for the cost over a five- to eight-year schedule.

Dredging the shipping channel to a greater depth is a top priority of the State Ports Authority, because larger, heavier container ships are expected to call on Southeast U.S. ports following an expansion of the Panama Canal that could be completed in 2014.

The channel is 45 feet deep. The SPA says it needs to be at least 50.

Studies began last summer, but the Corps had been saying that the deepening project, dubbed Post-45, would likely not be completed before 2024. That timeline has been blasted by critics.

Years-long studies have been the norm for U.S. ports seeking deeper water. In Georgia, the Port of Savannah has been seeking federal approval for deepening the Savannah River since 1996, and a final report was just issued by the Corps this year.

Georgia’s project is currently the subject of multiple legal challenges filed in South Carolina.

The timeline for Charleston’s Post-45 project was not firmed up until Wednesday morning. The Corps’ prior time estimates for the study have ranged from four to eight years.

The SPA says it already can accommodate some of the largest container ships that call on Southeast ports at high tide. Deepening the harbor would remove the tidal restriction.

SPA officials were scheduled to discuss the dredging project at noon.

Read more in Thursday’s editions of The Post and Courier and follow David Slade on Twitter @DSladeNews.