Posted on November 21, 2016
By Gary Walker, Argonaut Online
Four years after removing one million cubic yards of sediment from the mouth of Marina del Rey harbor, L.A. County officials are getting ready for another deep cleaning.
The dredging back in 2012 focused only on the south side of the harbor’s entrance. This time, they’re working on the north side, leaving the south side open to boat traffic.
Marine dredging contractor J. E. McAmis Inc. will set up shop on the north side of the harbor’s entrance on Saturday, Nov. 26, and begin removing an estimated 425,600 cubic yards of seafloor sediment the following Monday, said Carol Baker of L.A. County Department of Beaches and Harbors.
The 220’-by-60’ dredging vessel Heidi Renee, similar to the barge used in 2012, will be anchored at the north side of the channel.
Work is expected to continue around the clock for at least five months and will be supervised by the U.S. Army Corps of Engineers.
The south side of the harbor entrance is currently 28 feet deep, and the north side in need of dredging is right now only 16 feet deep, according to Beaches and Harbors.
The project’s nearly $2.7-million price tag is being paid with federal funding and is considered routine maintenance for the harbor.
While the current volume of sediment removal is much smaller than the last time around, 425,600 cubic yards is still a pretty big deal.
“It’s enough to fill a football field to a height of 255 feet,” Baker said.
The excavated sediment will be cleaned and processed before being used at Playa del Rey’s Dockweiler Beach to shore up the beach and prevent erosion, she said.
In 2012, workers spread approximately 140,000 cubic yards of cleaned sediment at Dockweiler.
Last time around, local water quality nonprofit Heal the Bay raised initial concerns about the cleanliness of sediment headed for Dockweiler, but the group worked with the California Coastal Commission on a process to clean the sediment headed for the beach.
Heal the Bay was unaware of the future dredging and sediment placement project until contacted by The Argonaut.
A team from the California Coastal Commission joined members of the Southern California Dredge Material Management Team and Contaminated Sediment Task Force on June 22 to review Marina del Rey’s sediment and chemistry results.
“[They] concurred with the suitability determination made by the Corps of Engineers for placement of dredged sediments either on or in the nearshore off Dockweiler Beach,” wrote California Coastal Commission Acting Director Jon Ainsworth to the Los Angeles office of the Army Corps of Engineers on Sept. 1.
“The sediments to be dredged are suitable for either beach or nearshore placement, based on physical or chemical testing of the dredge areas,” he wrote.
Projects that go before the task force are not presented to the public before environmental clearance is determined, but Heal the Bay would rather they were.
“The public needs to have an opportunity to see these projects prior to approval. And seeing them on a consent calendar does not count as public input,” said James Alamillio, manager of urban programs for Heal the Bay.
Ainsworth said that excavated sediment placed at Dockweiler will initially appear darker than the sand there now.
“However, once the dredge sediments dry they will lighten to match existing beach sands,” Ainsworth wrote.
While Baker stressed that the dredging is a necessary part of the harbor’s regular upkeep, there have been calls in the past that it should be happening more frequently.
“Marina del Rey is an anchor for tourism, recreation and public safety in Los Angeles. It is home to more than 5,000 boats, the U.S. Coast Guard and the Los Angeles County Sheriff’s Department. Although the marina should be dredged every three to five years, it has experienced waits two and three times longer than that,” reads a June 2013 letter from former Congressman Henry Waxman to U.S. Army Corps of Engineers Commanding Gen. Thomas Bostick.
Prior to 2012, Marina del Rey harbor hadn’t seen any dredging since 1999.
Source: Argonaut Online
