Preventing Agricultural Plastics from Entering NOAA’s National Marine Sanctuaries

An aerial view of a river cutting through agricultural fields as it heads towards the ocean.

A Federal Nissan Titan, a quadrat, and four rolls of soil-biodegradable mulch in the trunk.  First stop: a strawberry field in Oxnard, CA. Second stop: National Marine Sanctuary office at CalPoly. Third stop: the California Strawberry Center. Suspects on the run, but no need to stress! It’s the California Marine Sanctuary Foundation's Water Quality Protection Plasticulture Team making its rounds.

The CMSF investment in plasticulture pollution prevention started in 2019, with $11,000 of seed funding. Thanks to our collaborative approach and federal support, we have now turned that initial investment into a three-million-dollar endeavor. Plasticulture, referring to the plastic used in farms, has revolutionized agricultural production systems. Ag plastic films in row-crop systems suppress weeds, reduce agrochemical use, and conserve water. However, the breakdown and escape of the plastic can result in ag plastic entering waterways and oceans. In 2023, CSMF and the Ca- Sea Grant were awarded the NOAA Sea Grant – Marine Debris Challenge grant titled Commercially scalable end-of-life solutions for agriculture field plastic films used in watersheds draining to National Marine Sanctuaries, (Award NA23OAR4170176).

With significant investment from this grant, our partners at Flipping Iron and Andros Engineering have developed a dry-wash processing line aimed at addressing the biggest challenge to recycling agricultural films - high organic contamination. The process is simple: 

Step 1. Plastic mulch films are mechanically collected and densified using the Andros Megabinder@

Step 2. Plastic Mulch Film is processed via a dry-wash processing line, that uses no water to remove significant contamination from the mulch

Step 3. Processed plastic mulch is baled and sent out for recycling.

As we trailblaze towards addressing the challenge of high organic competition, we are training the next generation of water quality professionals. In 2024, Mikayla Nicols joined the team as our graduate student researcher, funded by NOAA Sea Grant. Ms. Nicols' work has focused on understanding the role of microplastic fate and distribution in agricultural watersheds. She led the analysis comparing different methods to remove plastic from fields. Her analysis found that there was no significant difference between hand removal of plastic mulch and removal with a mega binder (Sistla et al., Unpublished). This indicates that mechanical retrieval with the Megabinder@ can be adopted as an effective mulch removal technique compared to no removal or hand removal. She is also exploring the role of fence-lines in the movement of microplastics from the field. Now, Alena Anousinh, from our water quality team, will join as the second graduate student researcher. Through the NOAA Sea Grant Funding, the master's students receive funding for tuition, a stipend, and research supplies.  

As the Ca-Sea Grant team has mentioned, this NOAA funding has aided in the development of a platform for cross-sector members to join and advance technology, practices, transfer of knowledge to improve agricultural plastics recycling, and reduce waste, costs, and potential escape of ag plastics into the neighboring marine systems. Since the start of the Agriculture Water Quality Alliance, over 20 years ago, we have had one mission:  “protect and enhance water in the Monterey Bay National Marine Sanctuary  and the adjacent watersheds while sustaining a world-class production agriculture region.”  As we continue our journey across the Central Coast, we may pause to pose for a quick selfie with collaborators, but a stop is nowhere in the future for us.