Cairo,
Egypt (CNN)Efforts to dislodge the huge container ship stuck in the Suez Canal intensified Saturday as the backlog of ships at either end of the crucial waterway grew, heightening concerns over the impact of the blockage on global supply chains. The Ever Given, a container ship almost as long as the Empire State Building is tall, ran aground in the Egyptian canal on Tuesday after being caught in 40-knot winds and a sandstorm.
Since then, dredgers have been working to remove vast quantities of sand and mud from around the port side of the 224,000-ton vessel's bow.
A senior Suez Canal pilot told CNN the gigantic container ship could be dislodged by Saturday evening.
The pilot -- who is not authorized to speak to the media but works for the Suez Canal Authority (SCA) -- believes that several factors are now contributing to the anticipated success of the rescue operation including the near completion of the dredging work, the expected high tides and the availability of powerful tug boats.
High tide, expected at 10 p.m. local (4 p.m. ET), is an important factor in the rescue operation. Several other attempts over the past few days have failed.
A team of expert salvors from Dutch firm SMIT Salvage and Japan's Nippon Salvage -- who have worked on several high-profile operations in the past -- have been appointed to help the SCA re-float the ship, the charter company Evergreen Marine said in a statement.
Authorities say they have managed to remove almost 706,000 cubic feet of sand to free the Ever Given.
Asked if authorities had other plans in case of failure, the official told CNN: "This is our only option now."
Speaking at a news conference Saturday, SCA chairman Osama Rabie gave details of the rescue operation, which he described as "technically difficult" and "involving many factors."
"We are facing a difficult and complicated situation, we work in a rocky soil, the tides are very high, in addition to the huge size of the ship and the number of containers that make it difficult," he said. "We cannot set a specific date for the ship to float, it depends on the ship's response."
The ship was "very responsive" on Friday, leading to optimism that the job could be completed that night, he said. However, the operation had to be halted because of the tides.
Around 9,000 tons of ballast water have been removed from the ship, Rabie said, with the dredging taking place during low tides while 14 tugs worked during high tides. Rescue teams managed to temporarily restart the rudder and propellers on Friday night before a low tide stalled their efforts, he said.
In contrast to the pilot's comment, Rabie outlined another scenario that would require them to lighten the ship load by removing containers, a time-consuming and painstaking process to which they "hopefully" would not have to resort.
Around 321 ships are currently waiting to transit through the canal with no detours from inside the channel at this point, he said.
Rabie said the reasons behind the accident remain unclear. "There are many factors or reasons, fast winds and the sandstorm could have been a reason but not the main reason -- it could have been a technical mistake or human error," he said. "There will be further investigations."
Rabie added that a number of countries including the United States, China, Greece and the United Arab Emirates had offered assistance in dislodging the ship.
