BALTIMORE >> Crews opened a second temporary channel on Tuesday allowing a limited amount of marine traffic to bypass the mangled wreckage of Baltimore’s collapsed Francis Scott Key Bridge, which had blocked the vital port’s main shipping channel since its destruction one week ago.

Work is ongoing to open a third channel that will allow larger vessels to pass through the bottleneck and restore more commercial activity, officials announced at a news conference Tuesday afternoon. The channels are open primarily to vessels involved in the cleanup effort, along with some barges and tugs that have been stuck in the Port of Baltimore.

A tugboat pushing a fuel barge was the first vessel to use an alternate channel late Monday. It was supplying jet fuel to Delaware’s Dover Air Force Base.

Gov. Wes Moore said rough weather over the past two days has made the challenging salvage effort even more daunting. Conditions have been unsafe for divers trying to recover the bodies of the four construction workers believed trapped underwater in the wreckage.

“We promised these families that we would do everything in our power to bring them closure, but also my directive is to complete this mission with no injuries and no casualties,” Moore said.

Earlier Tuesday, Moore visited one of two centers the Small Business Administration opened to help companies get loans to assist them with losses caused by the disruption caused by the collapse.

U.S. Sen. Ben Cardin, a Democrat who accompanied Moore in meetings with potential loan applicants, said he spoke with truck drivers who relied on the port to supply their cargo. While they are already feeling the immediate economic effects of the collapse, he said, the ripple effects will be widespread — especially for small businesses, which he called “the growth engine of our nation.”

For Alex Del Sordo, who owns a marina and waterside restaurant near the collapse site, the future economic landscape is largely a mystery. So far, his businesses have been busy servicing boats involved in the recovery and salvage operation and offering discounted meals for first responders. He said he and his partner are considering applying for a low-interest loan.

He anticipates a decrease in pleasure boating because vessels moored in Baltimore’s harbor are temporarily trapped there. But he said rebuilding the Key Bridge will likely bring a large influx of labor and maritime traffic into the area and help keep some local businesses afloat.

“I think small businesses will have to be creative in what they offer,” he said.

In Annapolis, lawmakers held a hearing Tuesday afternoon for a bill authorizing use of the state’s rainy day fund to help port employees who are out of work and aren’t covered under unemployment insurance while the port is closed or partially closed. The bill also would let the governor use state reserves to help some small businesses avoid laying people off and to encourage companies that relocate to other ports to return to Baltimore when it reopens.

Lawmakers are working to pass the bill quickly in the last week of their legislative session, which ends Monday. The Maryland Senate Finance Committee voted 11-0 in favor Tuesday; it could be on the Senate floor as soon as Wednesday.

Meanwhile, crews are undertaking the complicated work of removing steel and concrete at the site of the collapse after a container ship lost power and crashed into one of the bridge’s supporting columns. Crews have described the mangled steel girders as “chaotic wreckage.”

U.S Army Corps of Engineers Col. Estee Pinchasin said the underwater conditions are “extremely unforgiving” for divers.

“The magnitude of this is enormous,” she said.

To open the second channel, crews used a large crane to lift wreckage out of the way.

Authorities believe six members of a road construction crew plunged to their deaths in the collapse, including two whose bodies were recovered last week. Two other workers survived.

Other vessels are also stuck in Baltimore’s harbor until shipping traffic can resume through the port, which is one of the largest on the East Coast and a symbol of the city’s maritime culture. It handles more cars and farm equipment than any other U.S. port.

Jim Roof, a longtime tugboat captain, said he’s waiting for a deeper channel to open before he can leave the harbor. He shook his head, thinking about the thousands of ships that have passed under the Key Bridge during his career.

“The system we have is pretty good,” he said, noting that in this case, the absolute worst possible timing caused a large-scale disaster.

The local nonprofit Baltimore International Seafarers’ Center has been in contact with the crews of some stationary ships, offering them support and transportation for shopping trips and other excursions.

Volunteer Rich Roca said seafaring is a tough job even in the best of times. Crew members often leave their homes and families for months on end. Some of those stuck in Baltimore are halfway around the world with no return in sight.

President Joe Biden, who has pledged significant federal resources to the recovery effort, is expected to visit the collapse site Friday.

The bridge fell after being struck by the cargo ship Dali, which lost power in the early hours of March 26, shortly after leaving Baltimore on its way to Sri Lanka. The ship issued a mayday alert, which allowed just enough time for police to stop traffic, but not enough to save a roadwork crew filling potholes on the bridge. The ship remains stationary, and its 21 crew members remain on board.

The Dali is managed by Synergy Marine Group and owned by Grace Ocean Private Ltd., both of Singapore. Danish shipping giant Maersk chartered the Dali.

Synergy and Grace Ocean filed a court petition Monday seeking to limit their legal liability, a routine but important procedure for cases litigated under U.S. maritime law. A federal court in Maryland will ultimately decide who is responsible and how much they owe.

Contributing to this report were Associated Press journalists Brian Witte in Annapolis; Tassanee Vegpongsa in Baltimore; Sarah Brumfield in Washington; Michael Kunzelman in College Park, Maryland; and Rebecca Boone in Boise, Idaho.