Updated 2 p.m. Thursday

As summer approaches, thousands will be visiting California’s beautiful rivers, whether to swim, kayak, tube or just relax on the shore.

But the waters may be especially fast-flowing, cold and dangerous at your favorite spot this year, and unfortunately might not have the conditions for the safe, fun visit you’re hoping for.

There have been several tragic incidents on California rivers in the past few months. Just last week, Will Hoxie died in the Kern River while kayaking. A 60-year-old man died boating on the South Fork American River. A 17-year-old drowned in the South Yuba River in April, and a man went missing in the American River later that month.

As the Fourth of July holiday approaches — a time when many in the Bay Area plan to escape the cities and head to the river — the National Weather Service’s Sacramento office has issued a stark warning about the freezing temperatures of the region’s rivers this year:

So why are our local rivers so much tougher this year? How can you check water flow online yourself, to determine whether a trip is too dangerous? KQED reached out to officials and experts for some answers on how to keep yourself and your family safe.

Why are our rivers so dangerous this year?

During summer recreation season each year — from roughly Memorial Day to Labor Day — California releases a huge amount of water from many of its dams into the rivers that flow below them. And this year, the melting snows from our recent epic winter mean there’s even more of that water.

“The rivers are very high, fast and cold because of the snowmelt. We’re getting hotter weather,” said Sarah Kennedy, the California State Parks boating safety education and outreach coordinator. “So the snowmelt is melting off quicker and creating more water than we’ve seen probably since 2017.”

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“We are still at like 70% snowpack, which means we have a lot of snow still to melt,” said Kennedy. “Usually at this time it’s kind of petering off.”

The flow of water in rivers is measured in cubic feet per second, and volume varies significantly from year to year depending on water levels — as does the length of time during which water is released.

Kennedy said the Kern River is flowing at an incredible rate — last week at about 5,049 cubic feet per second — which can hit the human body with incredible force. She likened it to someone “throwing 5,049 basketballs at you.”

“You can imagine if you’re standing there, you’re probably going to get hurt,” she said.

The data below shows yearly average outflow volume from the Folsom Dam on the American River from 2010 to 2023.

David Spencer is the ranger commander for the Sacramento County Department of Regional Parks, which manages the American River; Spencer says the American is flowing out of Lake Folsom at an incredible 6,500 cubic feet per second, more than three times the typical rate.

“That’s very fast for this time of the year,” Spencer said.

Kennedy predicts this high flow will last until the end of July or August.

Which rivers are most dangerous right now?

“Any rivers that are connected to the [Sierra Nevada] are really impacted at this time,” Kennedy said, citing rivers like the Yuba, American, Kern, Kings and Feather. (Keep reading for why going to the Yuba River is particularly discouraged this year.)

“It’s dangerous right now. And it’s not a good place to bring your family in,” she said. “It’s not a place to let your guard down right now.”

Kennedy says being on the rivers right now is for experienced kayakers and rafters only — but if visitors are looking for an exciting experience on the river itself, they should check out commercial guiding companies as a safer option.

But there is a difference between going into the river and just being near it — although the latter still demands caution, especially right now.

“I don’t think you should not visit the river,” said Kennedy. “But I think you need to take extreme caution. I don’t think people should be wading in the river. I don’t think people should be walking on slippery rocks.”

To see the status of a particular river, Kennedy recommends checking out Dreamflows and American Whitewater. On the maps you’ll find there, the color green denotes the rivers where the flow is safer — but even these rivers can have high flows that demand caution.

Spencer says officials are not going to keep anyone out of the American River through enforcement. He does, however, still recommend caution, especially with children.

Ken Casparis, spokesperson for Sacramento County, adds a note of optimism for the summer ahead. “Up until maybe last weekend, we were advising people to stay off [the American River] just because the flows were so high,” he said. “But they’ve really come down a bit in the last couple of weeks. So we’re seeing more manageable flows that are a little bit safer for people to recreate.”

Don’t go to the Yuba River in June

The Yuba River is a popular destination for folks from the Bay Area — the South Yuba draws almost a million visitors a year — often on account of its beautiful swimming holes. But Nevada County official Heidi Hall says she is encouraging “people really not to go at all” to the Yuba.

“We have had several deaths already,” said Hall, a supervisor for District 1, which includes the South Yuba. “Some of them are people slipping off a rock. So they’re not even intending to get in the water.”

A safety advisory issued by Nevada County officials back in April specifically warned would-be swimmers that “sudden immersion” in the South Yuba’s “icy” waters could result in cold-water shock, which “may look like involuntary gasping, panic, and hyperventilation.” Sharply inhaling air (or water) as a result of this shock, warned the county, “can immediately lead to the drowning process,” and “can trigger sudden changes in blood pressure, temporary paralysis, and cardiac arrest.”

It’s this “combination of swiftness and unusual coldness [that] means that we’re asking people to literally stay out of the river for the month of June,” said Hall.

Visitors may be safer in July.

What should people do to prepare when going to the river?

If you’re determined to visit the river this summer — again, Hall doesn’t advise visiting the Yuba River — here is a checklist of things to keep in mind:

• Have you checked online how swift the river is, using a resource like Dreamflows or American Whitewater?
• Do you have the right shoes to get down there, if a hike is required?
• Do you have enough drinkable water?
• Do you have enough food?
• Do you have a trash bag to pack out your litter?

You should also be ready to be in a remote area, potentially with no cell service or amenities. “You really need to be prepared to be out … in the wild for the day,” Hall said of any trip to a more remote river area.

Kennedy, the statewide education coordinator, says visitors should know where they are on the river, and whether there is a big rapid nearby. She suggests people not wade or swim right now, even if it looks calm.

The reason is hydraulic holes in the river, which can suck people in — even those with life jackets, she says.

Spencer, the ranger commander from Sacramento, asks people to have a plan when getting into the water and to have someone onshore who can track them, since the cold water can be quickly disorienting. See more water safety tips about the American River.

What if somebody gets into trouble in the water?

If you see someone in trouble in the water, or spot somebody falling in, don’t jump in after them. Kennedy says you should call 911, know your exact location and be able to describe what that person was wearing.

“It’s hard not to go after someone that you love, but … you’ll probably become a victim yourself,” she said. “And the best thing you can do is keep an eye on them, keep calm, know exactly where you are and be able to give good information to [911].”

On the American River, “we usually will have an airship in the air or they’ll get one in the air pretty quick to help locate these people. And knowing what they’re wearing really helps us,” Spencer said.

Sacramento County’s water safety guidance suggests yelling, “Help!” to draw attention if you spot someone in trouble in the water, and — if you’re able, without getting in the water yourself — reaching toward the person with a pole, branch or paddle, to help them stay afloat until they can get to shore or help arrives. If you have a life jacket or ice chest on hand, you could also throw that out.

To raise the chances of a person staying afloat, Nevada County official Hall says people can put their feet up, facing down the river, and try to go through the rapids to swim out.

Get a life jacket

All of the experts emphasized the importance of having a fitted life vest, especially those good for whitewater, even if you’re just fishing.

Find your county on this list to borrow a life jacket through the Life Jacket Loaner program. Children under 13 on the American River are required to wear a life vest.

Can you drink alcohol at the river?

Hall advises against bringing alcohol to the river, as it impairs judgment.

Spencer also said “a few of our parks have zero tolerance on alcohol. We enforce that pretty strictly.

“But if you’re going to choose to be in one of those parks that allows alcohol and you choose to be in the water, please be safe. You know, make sure that you don’t overestimate your abilities,” he said.

“Make sure people keep track of each other, and don’t hesitate to call 911, because seconds really count in the river,” urged Spencer.

If you’re pausing on river plans, check out the alternatives

Nevada County’s Hall says it’s safer to head to lakes or campgrounds near the Yuba River this summer.

“We have beautiful lakes up in the north, and we have hiking trails and biking trails, and obviously a lot to do downtown,” she said.

She suggests these alternatives near the Yuba that make for a safer visit, at least right now (be sure to check whether snow removal might still be affecting access):

• Sardine Lake
• Gold Lake (campgrounds are scheduled to open June 23)
• Grouse Ridge
• Scotts Flat Lake
• Recreation facilities in Grass Valley, Nevada City and Truckee
• Lions Lake at the Nevada County Fairgrounds in Grass Valley, which offers family-friendly fishing

“(The Yuba River) is spectacular. It is really worth visiting when it is safer,” Hall said. “The boulders are so beautiful and huge … And the water is clear. And there’s life in the river.”

“It’s a gorgeous river,” said Hall. “We just want you to wait until it’s safe to go visit it.”

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