The Los Angeles County Department of Public Works held a public meeting Wednesday, September 23rd to solicit input on the Oxford Retention Basin Flood Protection and Multi-use Enhancement Project in Marina del Rey.
The Public Works Watershed Management Division is relatively new in its organization, using a new approach of managing storm water not just as wastewater, but as a resource, said Greg Jaquez, an associate civil engineer.
Bruce Hamamoto, a civil engineer, said the department is in the early planning stages and wants input from the public regarding concerns and suggestions for the Oxford Lagoon.
The Oxford Basin is in part of the unincorporated area of Marina del Rey that is owned by Los Angeles County, and the county Flood Control District has rights on the property.
The focus of the project is for flood protection, operations and maintenance, water quality, aesthetics and recreation.
In the area of flood protection, the intent is to restore retention capacity of the Oxford Basin. After 40 years of operation, accumulated sediment has built up.
The project proposal is to address the installation of features in the Oxford Basin to help clean storm water runoff with an interchange of tidal flows into the basin during dry weather, letting out cleaner water from the basin than the water that comes in, and excavating sediment which is a major contributor of the discharge in Basin E, said Jaquez.
Runoff is mostly from the City of Los Angeles to the north, several hundred acres in Venice, a portion from Culver City, and some from the California Department of Transportation (Caltrans) right-of-way. The county runoff drains into the basin after entering the storm drains, he said.
Water quality is one of the biggest challenges — the Los Angeles Regional Water Quality Control Board administers water quality regulations that affect Marina del Rey — with impacts by bacteria and toxins, metals and organics identified as contaminants on Basins E, G and F, said Jaquez.
The project goal is for improved flood protection and water quality, as well as providing aesthetic open space and environmental aspects with natural vegetation landscaping, habitat and recreational opportunities.
At this time there’s a bike path available but not a lot of other elements, he said. The plan is to create a separate walking/jogging path around the entire basin, separate from the bike path on the perimeter, as well as observation decks and benches for bird watchers, said Juaquez.
CONCEPT PRESENTATION —
The Oxford Lagoon is slightly more than a ten-acre property and there are four main areas to cover — flood protection, water quality, habitat and aesthetics, Jaquez said.
Alternative 1 is a conventional emergent wetlands in the basin bottom with a berm-type separator placed between the two existing tide gates through which water is conveyed into Basin E in the Marina.
The berm between the two tide gates allows them to operate independently, so that water at high tide goes into one gate, passes through to the back end of the basin and comes around. It is then retained for some period, treated by wetland plants, and released at low tide through the other gate.
Alternative 2 is basically the same idea, with a berm separator and tidal circulation, but uses the floating island process, with the same effect of the type of treatment.
The floating island with some type of fringe planting around the basin has some benefits to operations that need to be conducted in the basin, providing the ability to get in and clean things out, said Jaquez.
Alternative 3 is also the floating island and fringe planting concept, but instead of tidal circulation to move water around, mechanical circulators would be used.
They have the advantage of moving the water in a circular fashion, bringing water up from the bottom of the basin to the surface and expose it to sunlight to promote “die-off” of the bad bacteria, said Jaquez.
Alternative 4 was recently developed and is a slight variation on Alternative 1— emergent wetlands with a berm separator that would cause tidal circulation, but instead of individual cells, it would be a narrow channel with free flow all the way through, passing through side slopes and wetland plants.
Jaquez said that the project will be funded by various sources. It is a flood protection facility and owned by Los Angeles County.
The cost for the project is estimated at $11.3 million.
This process is expected to be completed around June 2011, and with the extensive permit requirements, construction could begin some time in 2012, according to Jaquez.
PUBLIC COMMENT —
Venice resident Steve Freedman said that the basin has been full all this time and he asked about the bioremediation being conducted already.
Jaquez said the reason bioremediation efforts are occurring is because they are eliminating algae odor problems and help officials understand the effectiveness of the method.
David DeLange, who said he is concerned about the nesting cycle for the birds, added that the construction scheduled would take place at this most vulnerable time, from January to mid-April.
“If you want birds for people to enjoy, don’t innocently disturb them with noises and vibrations within 300 feet of the nest since that would be a danger zone,” he said.
One speaker said that an observation deck shouldn’t be near bird nests.
Hamamoto said that nesting birds is a major concern. The department will have a biological consultant from Beaches and Harbors to consult with and will have constraints placed on windows during construction.
A resident near Oxford Lagoon said that since trees were removed at the lagoon, there is a higher noise volume from Admiralty Way, and he wanted to know about new landscaping to buffer the noise.
Landscaping will include drought resistant plants and the project would also address a noise buffer, Hamamoto said.
John Rizzo said that fences detract from recreation and parks, and they should be used only where required for safety. If a fence is needed, a low fence could be used, he said, pointing out that there are no fences at the canals and the beach.
He also suggested utilizing all or some of the parking lot next to the Marina International Hotel.
Rizzo suggested hiring a consultant to overlook the plan and make recommendations.
“Once it’s done, it’s done. It took 30 years to get this started, and it will be here at least another 30 years, so make it as good as you can,” he said.
Hamamoto said that fences would be minimized, but the department has to consider safety and health issues.
One speaker noted that when the tide goes out, some birds need minimal water levels to look for food. The speaker said other birds require a higher level of water to catch fish, and Hamamoto responded that this could be addressed with the tide gates mechanized to control flow.
A resident who lives near the lagoons said she is concerned about security issues on the bike path. She claimed that bicyclists urinate on the path, graffiti is present, and drinking and inappropriate behavior take place during the day.
Another speaker was concerned about toxic bacteria in the water. Hamamoto said the department encounters pollutants throughout Los Angeles County all the time, but steps are being taken.
“It is not an air quality concern; this is in the water, and it’s not a public health concern for people walking by the lagoon,” he said.
Pollutants come from runoff of street and property surfaces when it rains, he said.
Ballona Institute co-director Marcia Hanscom said she supports parts of the project including Alternative 4 because it’s a little less “mechanistic,” the interpretive signage, a platform for observation and local plants.
Hanscom said that allowing the natural tide to flow in and out is better, and that treating sludge and algae by keeping the gates closed makes no sense.
“The more man-made things there are to deal with, the more expensive for upkeep,” she said. “Night lighting is also disturbing to the birds.”
Tony P’s restaurant owner Tony Palermo said that he wants people to be able to walk to the restaurant and that fences have been a border between Venice and Marina del Rey for years.
Hamamoto said fences are required so that people don’t fall in the water and drown, but a certain type of fence could be placed further in and only a small part would be visible, making it a “friendlier” environment.
Hamamoto said that Public Works is responsible for flood control and resources at the water line, and Beaches and Harbors oversees the perimeter. He said they would be open to other groups for assistance, perhaps for special amenities outside the scope of the project.
Marina del Rey resident Dorothy Franklin said she would like a pedestrian bridge on Admiralty Way that goes over to the Washington Boulevard portion to provide an access point.
Venice resident DeDe Audet asked what kind of rain the county is prepared for, saying there is a diversion unit on Washington Boulevard that takes care of water along that roadway, but it doesn’t handle storm flow from Lincoln Boulevard.
Hamamoto said that approximately 15,000 cubic yards of sediment could be removed and that an entirely new storm drain would be installed at Oxford.
He said the floating wetland would be good for birds and the basin could be contoured for needed capacity but also to serve the wetlands.
The bottom of the lagoon is filled with sediment and if the material can be excavated a little deeper in some parts and less in others, choosing where to remove material and how to grade it to benefit the habitat would be preferable.
Roy van de Hoek of the Ballona Institute said the county needs at least one expert tidal hydrologist always on duty which could involve local citizens. A bridge is also a good idea, as it allows birds to rest on it, he said.
Fencing should be waist high, but not obstruct the view, he said, noting that Admiralty Way also has a high fence. The project would also require a lot of expensive shoring up for a stable walking path on that side, and a boardwalk on stilts might work, he said.
Resident Nancy Vernon Marino said that for years the area has been posted as a bird sanctuary and recommended that a biologist/ornithologist be on staff. Hamamoto said that Beaches and Harbors has staff consultants, but they would consider a wildlife consultant.
Information, (case sensitive)
ftp://dpwftp.co.la.us/pub/wmd/Marina del Rey/Oxford Basin.