That is in the town of Cannon Beach and those elk are in and around town all the time and often seen right on the beach and even out in the shallow surf. There's a creek that dumps into the ocean right where they were that during high tides, especially the King tide series they experienced lately, big swell can push a lot of water up there quite quickly as the video shows.
But elk on the beach in that area is not a rarity.
Well back in the 1980s they had this sight in Utah. The DWR transplanted a herd from the Oquirrh Mts to Antelope island. Within a few months all the elk swam back across the lake back to the Oquirrhs. The DWR never made that mistake again. Though the swimmers at Salt Air beach got a good view of elk swimming