April 10, 2020:
I personally experienced the great Santa Barbara oil spill of 1968 when I came out of the ocean covered in it.
I was snorkeling off La Jolla Caves, but after only a few minutes it was obvious there was something wrong with the water.
It was weeks before it was all out of my hair.
I loved that spot because on days of clear water the kelp forest was gorgeous. Even without a corrective dive mask I could see well enough to be gobsmacked. I went there again and again, sometimes with a guardian adult, often alone on my bike with my mask-snorkel-fins bungee'd to the rack in back, on days when I should have been in school.
It actually was best there in fall. The water was still warm but there was no-one around, and for whatever reason the water was often more clear then than in summer.
It's closed now. Cordoned-off by barrier ropes you could easily get around; but when I visited last it was empty. That may likely be because the sandstone shelf you scamper across to reach the cave front is now heavily eroded and crumbling. Or it might perhaps be because too many snorkeling tourists were damaging the ecological preserve. Or maybe someone else had chosen to dive from the cliff top, as according to clippings in the Cave shop a woman had done, twice, a hundred years before, both times breaking her neck. Whatever the reason, when I last visited the water was empty, and black.