OAKLEY -- For years, a piece of Delta history stood tall, if not a little lopsided, along the banks of the San Joaquin River at Big Break Regional Shoreline Park. A boom from a former clamshell dredge stood proud as an icon of sorts; however, most people didn't even know what it was or its significance to the history of the California Delta.

Last summer, a loud cracking noise was heard clear into the connecting neighborhood to the park, causing the boom to list just a little bit more, but it held in place. That was until a windy, rainy few days at the end of February, when the boom that stood across from the pier at the East Bay Regional Park District site finally lost its battle and fell completely to the ground.

The Big Break Regional Shoreline Park historical icon that fell into the water earlier this year during a bad storm in Oakley, Calif., is shown on Friday,
The Big Break Regional Shoreline Park historical icon that fell into the water earlier this year during a bad storm in Oakley, Calif., is shown on Friday, May 9, 2014. The icon was originally the "boom" of a small clamshell dredge that was abandoned on the property before the park district purchased the property. The East Bay Regional Park District staff is looking into the history of the boom to try to get an idea of how old it was and what it was used for. (Dan Rosenstrauch/Bay Area News Group) ( DAN ROSENSTRAUCH )

The story of this icon doesn't end there; the park district intends to leave the remnants of the boom in place, and is encouraging some of the district's interns to look into its past.

"The Delta is an ever-changing place, and Big Break is a great example of this," said Kevin Damstra, a naturalist at the park. "The clamshell dredge historically helped build the human-influenced Delta that exists today. It provided habitat for the plants and animals who make these waters home when it stood, and continues to today after its inevitable collapse."

Although the A-frame is no longer standing, the story of this clamshell dredge continues to showcase the interaction between the human and ecological world that coexist in the Delta, Damstra said.

"To our knowledge, the dredge was abandoned in the park before it was a park and is now a relic of our cultural history," Damstra said. "There are no plans to remove the wreck, just as the other historic wrecks throughout the park remain. I am unaware who owned the dredge before it was abandoned here."

Unlike the load-cracking noise last summer, Damstra said the fall of the boom, which took place overnight between Feb. 26 and 27, was not heard during the rainstorm.

The Big Break Regional Shoreline Park historical icon that fell into the water earlier this year during a bad storm in Oakley, Calif., is shown on Friday,
The Big Break Regional Shoreline Park historical icon that fell into the water earlier this year during a bad storm in Oakley, Calif., is shown on Friday, May 9, 2014. The icon was originally the "boom" of a small clamshell dredge that was abandoned on the property before the park district purchased the property. The East Bay Regional Park District staff is looking into the history of the boom to try to get an idea of how old it was and what it was used for. (Dan Rosenstrauch/Bay Area News Group) ( DAN ROSENSTRAUCH )

"So this icon of Big Break quietly sank into the Delta it helped build," he said.

Clamshell dredges have a vast history in the Sacramento-San Joaquin Delta. Because the park district doesn't know for sure where it came from, it doesn't know when it was made or for what purpose.

One of the district's interns, David Marsh, has been researching the style and make of the dredge that the boom might have come from. The interns hope to get a chance to measure the boom.

"We believe the dredge was built in the early 1900s and was definitely on the smaller size of Delta clamshell dredges," Damstra said.

Clamshell dredges were introduced to the Sacramento-San Joaquin River Delta in 1879 and replaced manual labor forces that shored up the many Delta islands with levees. These dredges were used to remove sand, silt and peat from the riverbeds to increase the size of levee barriers.

The Big Break area, where the park is located, was once a leveed shoreline. However, a "big break" in 1928 covered the levee with water between Dutch Slough and the San Joaquin River, flooding the asparagus farmland that previous existed along the shoreline. The levee was never rebuilt, but dredges were used to clean up the area.

Members of the Dutra Group, a five-generation dredging company and owner of the Dutra Museum of Dredging out of Rio Vista, speculate that because of the smaller size of this dredge, it is possible that it was used in the flooding of Franks Tract in 1936 or when it flooded again in 1938.

"I believe it is a small clamshell dredge built by Stockton Iron Works with a 1.5 cubic yard bucket. There was a series of these built to reclaim some of the smaller tracts in the Delta," Bill Dutra said. "I believe this rig, along with others, was used to reclaim Franks Tract the first time it flooded."

He went on to explain that Franks Tract flooded again in the second year after its reclamation, and the landowners went bankrupt.

"The dredges that were used in the reclamation were then moved to just beyond the Jersey Island area, where Big Break is today," he said.

Big Break Regional Park is looking for more details about the dredge.

Those with information are welcome to drop by the visitor center to talk with naturalists so that they can continue to share the history of the boom with park visitors.

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