Inside the buckets used to gather trash found tangled in shrubs and collected along the seawall at Horseshoe Cove were two mismatched shoes, food wrappers and a whole lot of cigarette butts.

With the Golden Gate Bridge towering behind them, 20 volunteers from across the Bay Area combed through a half mile of the area’s coastline and trails collecting the garbage.

The effort was one of more than 900 across the state and 45 across Marin that were part of Saturday’s 32nd Annual California Coastal Cleanup Day.

“It has enormous significance for the health of our coast and ocean,” said Eben Schwartz, California Coastal Commission’s coastal cleanup day director overseeing the statewide operations. “Once the rains hit, all of that trash gets washed out through creeks and storm drains and ends up in our oceans and on our coastline where it can cause tremendous damage and harm to marine wildlife.”

State officials expected more than one million pounds of trash and recyclables to be removed from the state’s coastline and waterways in the one-day cleanup event.

The more than 900 volunteers at Marin’s sites were estimated to have picked up 10,798 pounds of trash in preliminary counts, according to Joanne Jarvis, coordinator for the cleanups across Marin.

“It’s the largest volunteer event in California,” said Jarvis, a park ranger and volunteer coordinator at the Bay Model. “It’s a way to maintain our waterways and oceans and keep them clean. It gives stewardship to our beaches. We want to keep them in good shape because we love them.”

Christina Orth, of Mill Valley, used a trash picker as she picked up cigarette butts, many from foreign countries, and large flecks of glitter on a trail running through Horseshoe Cove.

Though the 69-year-old has participated in the cleanup day before, this year marked her first time volunteering at the cove, she said.

Orth said she felt compelled to help at the site after noticing a lot of garbage near the Golden Gate Bridge during a recent hike.

“I was hiking here last week and I noticed, especially under the bridge, I noticed how much litter there was,” she said.

Rachel Danielson, of Pleasanton, climbed the rocks beyond the seawall where the waters of the San Francisco Bay gently lapped.

She crouched as she sifted through sand, attempting to pick up tiny bits of broken Styrofoam.

“I guess it just makes me sad to see so much trash in natural areas,” the 25-year-old said. “I feel like people should put in more effort to clean up after themselves.”

Bob Benson, of Lafayette, shared that thought.

He said he is bothered by litter. It is crucial to pick up trash before it makes its way to the oceans, the 68-year-old said.

“The small plastic pieces break up and get in the food chain — fish are ingesting them,” he said. “It’s a big deal.”

As Benson walked along the bay in search of trash, he found not only cigarette butts and wrappers but two mismatched shoes only 200 feet apart.

Multiple buckets were already filled with garbage an hour into the event at Horseshoe Cove.

But Steve Kasierski, the Fort Baker-based National Park Service official who has organized the cleanup at the site the last 10 years, said there is less trash in the area than in prior years.

“I am encouraged,” he said. “I am not seeing the same volume we would see on the same day of the year. We know there’s other volunteer groups that go out and clean things up, but we’re seeing less and less over the years.”

Kasierski said the event is significant because it connects people positively with nature and provides them with a sense of place.

“It’s the notion of volunteerism and stewardship, which we try to encourage a lot as park staff,” he said. “Our particular park, we have an incredible amount of volunteers. It’s what helps make everything work.”