Beaches in San Francisco are great for walking, surfing or just enjoying the view, but there is a serious danger lurking in the water that visitors should be aware of. And it's not the Great White Sharks!
Great White Sharks are numerous in the waters off San Francisco, but they are rarely a problem. The big danger is the rip currents that form just off the beaches in San Francisco, especially at Ocean Beach. There are some small warning signs, but most beach-goers don't really understand the risks.
I'm including this page because I don't think the city does enough to warn people about the very real hazards of swimming at beaches in San Francisco. Almost every year, people drown at Ocean Beach, and most of those deaths could have been prevented. An unpleasant topic, but necessary I believe.
A rip current is a strong current that flows away from the beach, out to sea in a sand channel.
Image courtesy of the United States Lifesaving Association
The incoming waves bring tons of water to the beach, but the return flow is blocked by sand bars, so the water rushes sideways until it gets to a break in the sand bar. Then massive amounts of water pour out to sea in the narrow (or not so narrow) channel.
The force of the water is so great that even a strong swimmer will be carried out past the breakers. Drownings usually occur when a less-experienced swimmer gets knocked down by a wave and sucked out to sea; the impulse is to fight the current and try to swim back to the beach, but that doesn't work. The swimmer becomes exhausted, or panics, and can't stay afloat.
Rip currents are sneaky; often you can't see them and they move around.
Here is a brief film with footage of actual rip currents on an Australian beach. If you look closely, you can see a narrow stream of water heading away from the beach, even as the breakers are rolling in. As you can see, they're not easy to spot; and they are not always as obvious as the ones in the video.
Knowing what to do can often make the difference between living and dying.
If you get pulled into a rip current, the best thing to do is stay calm and try to keep your head above water. Rip currents are not undertows. The word "undertow" is now out of favor and no longer used "officially"; the current flows horizontally, so you are not pulled under water unless the beach is very steep.
Don't fight the current. Never try to swim back to shore against the current; that is usually when the drownings occur.
If you can, swim at right angles to the current, parallel to the beach, to get yourself out of the current. Once you are free of the current, swim toward the beach at a 45 degree angle away from the rip current so you don't drift back into it.
If you can't swim out of the current, let it carry you out. The current will peter out at some point, past the breakers usually, and you can then swim parallel to the beach a little way and then head back to the beach at an angle away from the current.
Shout for help and wave if you feel you can't swim back or are losing strength.
If you see someone else has been caught in a rip current, shout out instructions for swimming out of the current and throw them a floating device of some kind if possible. Be very careful about going into the current to save them, unless you are a strong swimmer and know what you are doing. Many have drowned trying to save others.
Of course, the best thing is not to get pulled into a rip current in the first place. Beaches in San Francisco are not safe for swimming, and that goes double for Ocean Beach, which has the worst rip currents and most drownings.More information on rip currents from the United States Lifesaving Association.
Here's a tempting mini-beach in a beautiful setting at the foot of the Cliff House, near Seal Rock. Don't do it! The incoming tide could trap you there.
Probably only at Aquatic Park (near Fisherman's Wharf), where there is a wall or breakwater around most of the swimming area. And some people do swim at China Beach, though I wouldn't say it was particularly safe; there's a strong current flowing out to sea there. See San Francisco Beaches for a list, photos and map of the beaches in San Francisco.
In spite of all these warnings, beaches in San Francisco are great places to spend the day!