Eleven-year-old Toots Park began her Saturday by picking up rocks.

She was one of about 100 volunteers who spent part of the morning picking up coral rocks along the shoreline at Ala Moana Beach Park as part of a cleanup project organized by the city Department of Parks and Recreation.

“It was kind of hard, digging the rocks because some of them wouldn’t come out,” said the braces-wearing Kaneohe resident, who was visiting the park for the first time. But she said she enjoyed herself, not only because she likes to clean, but because she was helping others have a better beachgoing experience.

“It’s going to help them so it’s not dangerous,” said Park, who was volunteering with her softball team, Hawaii Titans Fastpitch. “If they step on the rock they’ll get hurt, but now most of the rocks are gone, so they won’t get hurt as much.”

The effort is part of Mayor Kirk Caldwell’s nine-point action plan for immediate improvements to Ala Moana, known as the “People’s Park,” which receives about 4 million visitors a year.

The city has made progress on several points of the plan, announced last year, such as repaving the exercise path and renovating a comfort station on Magic Island. Last month, the city began planting new trees along Ala Moana Boulevard and is working on an irrigation system.

Saturday’s cleanup removed rocks in the sand, exposed by erosion, that made it difficult for beachgoers to walk near the water across from McCoy Pavilion. The city is planning to move sand to the same area from the Diamond Head and Ewa ends of the beach park later this year, widening the beach.

David Smith, a coastal engineer with Sea Engineering, which is assisting the city with the project, said the nettlesome coral comes from the reef that had been dredged to make the beach park’s swimming lagoon and deposited into a canal that is now the beach.

Some of the rocks cleared away Saturday from a roughly 100-yard stretch of sand were as large as beach balls. Volunteers dug them out with shovels and hand-carried them away because federal rules prohibit the use of machinery to move material in the water without a permit.

Once removed, the rocks were carried in buckets and dumped in trenches on the beach that were later covered with sand. The rocks were buried because state law prohibits removing beach material, Smith said.

Engineers estimated the volunteers removed at least 25 cubic yards of rock from the shoreline. Some rocks, however, were fused to the bedrock and stayed in place.

“You can already see, look how much clearer it is without the rocks,” said Jeanne Ishikawa, deputy director of the Department of Parks and Recreation, noting that the event gave people an opportunity to know that they helped improve the park. “I think it’s amazing.”

Glenn Yee, of Aiea, who was volunteering with his wife at the cleanup, said he often stubbed his toe on the rocks as he entered the water to go swimming.

“I complain about the rocks,” he said. “Now’s a good chance to take action.”

Gregg Horita, president of Hawaii Titans Fastpitch, said his group brought about 50 girls to help with the cleanup and regularly participates in community projects around the island.

Horita said he encourages his players to volunteer for cleanup projects because it instills a sense of pride.

“It’s like your backyard,” he said. “If you take care of it, it’ll take care of you.”