SAN FRANCISCO (KGO) --The massive amount of debris is creating problems for ferry boats and other vessels. Cleanup has been underway, but the reality is that crews can't work fast enough to remove all of the stuff left by the storms.
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A carpet of debris at the Vallejo Harbor can be seen from above. A crew from the Army Corps of Engineers started their day there.
"So we got on one scene and the first thing we saw was this," said Kixon Meyer of the Army Corps of Engineers, indicating to a big hunk of tree. "And this weighs about two tons and approximately 45 feet long."
They're finding a lot of big trees.
Wednesday morning their ship The Dillard towed in two seven-ton trees all floating down from the Sacramento Delta.
Their second boat, the Raccoon, was also doing some heavy lifting.
"Now that we've had some high tides, a lot of rain, they're just coming off the banks," said Meyer.
"You can actually feel the water with your fingers squishing out when you push it," Meyer told ABC7 News. "Doesn't require a lot of pressure to do that."
The saturation allows the trees to float close to the surface.
Sometimes boats don't see them because they're covered with hyacinth, an invasive, non-native aquatic weed.
"When you are traversing the bay, that stuff can get stuck up in the engine and seize up your engine," said Director of the Pier 39 Marina Sheila Chandor. "And you would have to change your props."
Crews from the Gemini ferry boat were fixing the propeller Wednesday morning. It was damaged after hitting debris.
Ferry boats are reducing their speed and weaving in and out to avoid hitting anything that can cause serious damage. Not since El Nino of 1997 have people seen this much litter in the bay.
People swimming Wednesday confronted several obstacles. The beach at Aquatic Park was covered with twigs and larger pieces of wood.
"There are also some big logs out there so you have to be careful," said San Francisco Bay swimmer John Rohosky.
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Most of the trees will be hauled away and eventually reused.