Although up for debate, it’s long been theorized that the maritime civilization of the Polynesians made contact with the Chumash. However recent evidence suggests this may be more probable than once thought.
The Pacific Ocean is the largest ocean in the world. It is fair to say navigation across it, even by modern methods, is an incredible feat. Even Western Empires, in their large vessels exclusively fitted for global explorations, struggled to navigate the Pacific. Harsh tropical storms, lack of food and water, and clashing currents of ocean and wind would often blow them off course to be eventually taken by the sea. Knowing this, one would assume it would be near impossible for a small Polenesian vessel to make it across these waters since even an English Galleon couldn’t fare the tides. Surprisingly however, evidence of the Polynesians success lies within a humble potato.
Although direct evidence of contact in America is scarce, there is one mystery that seems to perplex scientists to this day, sweet potatoes. Sweet potatoes, native to South America, seem to have miraculously found themselves within the archeological evidence of the Polynesians diet. Presumably, the Polynesian sailors ventured to South America, obtained the sweet potato, and then brought it back to grow in Polynesia. If the Polynesians made it to South America, why couldn't they have made it to Southern California or even Malibu Riviera? Well modern linguistics and evidence from Chumash fishing boats could hold the answer to this question.
The Chumash, being a coastal peoples, the ocean was an integral part of their lives. Most native American Canoes were relatively simple, ussally made from a hollowed out log or bundled reeds. However, the boat of choice for the Chumash was actually much more complex than that. The Cumash vessel called the Tomol was a boat made from sown planks. Constructing it required cutting planks of wood, heating them in hot water, bending them into streamline shapes, then drilling holes into the wood allowing for the planks to be sewn together with a strong plant fiber like those from the yucca. Finally tar was affixed to the gaps between the planks making them water tight. “The resulting vessel was sleek, lightweight, fast and durable, or the perfect vehicle for long-distance travel through choppy waters, including deep- sea fishing areas.” The complexity of the Tomol showed that the boat itself was a highly engineered vehicle, contrasting almost all other Native tribes within the Americas. “Among North American Indians, only the Chumash, and later the neighboring Gabrielino, built sewn-plank canoes. In the Western Hemisphere, this technology is otherwise known only from the coast of Chile and among Pacific Islanders. The tomols surprisingly were able to carry large loads for long distances which allowed for navigation across the Pacific.” So where did the Chumash learn to build such a boat? One theory suggests that they learned their shipbuilding from the Polynesians.
First of all, the building process of the Tomol was very similar to that of the Polynesians, including ingredients and tools used to make the boats. Additionally, the sewn plank boats can be easily compared to eachother in that, despite sails in some of the Polynesian vessels, the body of the two ships carried a strong resembelance. 
“The Chumash word for "sewn-plank canoe" is tomolo'o, while the Hawaiian word for "useful tree" is kumulaa'au. The Polynesians colonized Hawaii during the first millennium A.D., and in the process their language evolved into the Hawaiian language. The Polynesian word tumu means tree or tree-trunk, and ra'akau means wood or branch;” Kathryn A. Klar, a linguist of UC Berkeley says, “complex linguistic analysis shows how the combination of those two words evolved into the Hawaiian kumulaa'au. Many Hawaiian words that start with "k" originally began with "t." Replace the "k" in kumulaa'au with a "t" and the similarity between the words becomes obvious. The similarity is so great, Klar says, that it is highly unlikely to be a coincidence.”
While still widely controversial and with many gaps left to fill in, there is much evidence to suggest that the Polynesians, even if not making contact with the Chumash, most certainly made it to South America. However, if this is true, it is more than likely that the Polynesians were able to sail up the coast eventually making contact with the Chumash Native Americans. Cross Pacific contact, and maybe even trade between the Polynesians and the Chumash, would change our perception of American Anthropology forever.
The Chumash were blessed with the rich coastal waters, bountiful esturaries, and coastal gardens of the Pacific Ocean. Imagine waking up every day at 23038 Pacific Coast Hwy and looking upon these same sacred waters that provided life to such a significant and historical group of people.
Sources:
https://www.sfgate.com/news/article/Did-ancient-Polynesians-visit-California-Maybe-2661327.php
https://www.parks.ca.gov/?page_id=24433