There are several reasons why the Interceptor’s second boom may remain deployed when it is not raining.
The transport of trash within Ballona Creek is affected by rainstorms and tidal influence. Flows from rainstorms carry trash and debris downstream towards the Interceptor and the ocean. Tidal influence can push trash and debris upstream before it can be collected by the Interceptor or back downstream towards the ocean. As trash travels within the creek, some trash and debris could end up on the banks and remain there until a high tide lifts the trash back into the creek. These cycles of high and low tides can cause large amounts of trash to remain in the creek long after a storm has passed. To prevent that trash and debris from reaching the ocean, the second boom remains deployed to help direct the trash to the Interceptor for collection.
The second boom remains available and ready for deployment as needed throughout the year, and may also remain deployed if additional storms have been forecasted in the near future
A notification is posted on our homepage whenever both booms are deployed. In addition, email notices are sent approximately 48 hours before the deployment of the second boom. If you would like to receive those updates, please email us at BallonaInterceptor@pw.lacounty.gov to be added to the mailing list.
The Ocean Cleanup is on a mission to tackle the world’s 1,000 most polluting rivers, which can be seen on the interactive map at https://theoceancleanup.com/sources. The peer-reviewed paper behind the model was published in the scientific Journal Science Advances in April 2021. Currently, The Ocean Cleanup’s focus is on regions where the problem appears most imminent; therefore, The Ocean Cleanup is not prioritizing other Interceptor projects in the US. Based on the paper’s findings, The Ocean Cleanup’s initial efforts have been focused on Southeast Asia, Central America, and the Caribbean.
This is a question that will be considered during the Pilot Project or subsequent to its completion. The Pilot Project is considered a proof-of-concept, and the results of the pilot will help inform the type of trash capture solutions that could be implemented throughout the region.
The cost of designing and permitting is estimated at approximately $1.3M. Construction of the moorings to secure the Interceptor and booms in place is estimated to cost $1.5M. The Interceptor is being provided to LA County for free from The Ocean Cleanup.
The Pilot Project is not expected to adversely affect wildlife. The conveyor belt on the Interceptor moves at a slow speed, giving animals ample time to return to the water. Holes in the conveyor belt will allow small animals to pass through the belt and re-enter the water should they interact with it. The Flood Control District and The Ocean Cleanup also intend for the Pilot Project to be iterative; as the Pilot Project moves forward, the District and The Ocean Cleanup will be able to alter and improve the Pilot Project to increase efficiency and avoid any negative interactions or impacts on wildlife and the environment.
Public Works is working on developing a trash characterization program to identify the various types of trash and debris that reach the Pilot Project site. All trash collected will be taken to an appropriate solid waste facility. When possible, trash will be taken to a Materials Recovery Facility for separation and recycling.
During the recent community meeting on March 23, attendees raised concerns that the existing Lincoln trash boom would be temporarily removed to test the effectiveness of the Interceptor. We have heard their concerns loud and clear, and our current plans are to continue to keep the Lincoln boom in place for the duration of the pilot period.
Yes, the Interceptor is powered by solar panels on the roof of the boat and is fully automated. As the Interceptor’s conveyor belt extracts debris from the water onto the shuttle, the shuttle equally distributes waste into the six dumpsters located on a separate barge within the Interceptor. At any time, operators can remotely access the Interceptor’s dashboards. Once the trash bins are full, the Interceptor will automatically send a message to local operators. While the Interceptor itself functions autonomously, maintenance crews will empty the dumpsters and perform routine maintenance activities as appropriate.
The Interceptor will be emptied after each storm event with a daily rainfall intensity of 1” or greater. Per our hydrologic records and rainfall data for the last ten (10) storms seasons (from October to April), the average number of storms with a daily rainfall intensity of 1” or greater for the Ballona Creek watershed was 2.3. Therefore, we anticipate that Interceptor will be emptied 2-4 times per storm season. However, this number will vary from year to year. During non-storm season months, trash will be removed as needed, and is anticipated to occur much less frequently. The barge will be removed from the interceptor, hauled over to Marina del Rey where the trash is offloaded, and finally returned to The Interceptor. Removal and replacement of the barge from The Interceptor will be done as quickly as possible and is not expected to occur over more than one day.
Most of the year, only one of the Interceptor’s trash booms will be installed. Thus, boats and rowers will be able to travel up and down Ballona Creek past the Pilot Project site unrestricted. During the storm season, Public Works will monitor weather reports and deploy the Interceptor’s second trash boom in anticipation of high-trash flow events. When both trash booms are deployed, boats and rowers will not be able to travel past the Pilot Project site. Once the storm has subsided and the Interceptor has collected the trash behind the trash booms, the second boom will be removed.
The Interceptor is equipped with standard white navigation lights for safety purposes. Additionally, there are LED strips around the opening of the canopy. These lights are designed so they do not shine light on the water surface, minimizing potential glare from the water reflection. Reflective ribbon may be installed on the Interceptor as a bird deterrent. In short, the lighting generated from the interceptor should not stand out greatly in comparison to the surrounding lighting conditions.
The trash being collected is expected to be 75% inorganics, which have less potential to generate odors compared to organics. Any odors associated are anticipated to be localized on the interceptor itself. Additionally, the collection bins are perforated to help drain the trash collected, removing excess moisture and helping to minimize odor impacts.
The Interceptor has minimal mechanical components, with the loudest part being the conveyor belt operation. While the conveyor belt is running, the noise level at the Interceptor will be 60 to 70 decibels if you were to stand on the Interceptor. From the nearest residential area, the maximum projected increase in noise is 0.4 decibels. For reference, a normal speaking voice is equivalent to around 60 decibels, and a whisper is about 30 decibels. Studies show that a 1 dB change in sound level is hard to notice, a 3 dB change is clearly noticeable, and a 10 dB increase will be nearly twice as loud. In summary, the analysis shows that noise will not be an impact as the surrounding noise will be more audible than the noise level from the Interceptor itself.
Currently, there is a trash boom deployed within Ballona Creek at Lincoln Blvd as well as the Trash Free contract (trash clean-up along the creek beds). To increase awareness of the trash issue, Public Works has engaged the public in the form of a “Trash Travels” and a “Don’t Waste Beautiful” anti-littering campaign. There is also concurrent planning and development of a long-term Trash Capture Project involving an automatic trash rack and a trash boom to divert trash into the trash rack.
The Ocean Cleanup conducted Environmental Assessments for the other locations, and Public Works did additional environmental analysis, specifically in regard to lighting, noise, odor, and vectors. As this project is considered a temporary pilot project, it is currently exempt under CEQA. However, at the end of the pilot period, additional analysis and a public CEQA process will need to be conducted to determine an appropriate permanent location for the Interceptor moving forward.