Backpacking Thousand Island Lake near Mammoth, California.

(aka that one time I went backpacking with the stomach flu)


Thousand Island Lake Permit Information.

Thousand Island Lake is in the Ansel Adams Wilderness outside of Mammoth, California on the ancestral homeland of the Paiute, Miwok, Mono, and Shoshone tribes. You need a permit to camp overnight, and there are multiple trails to hike in on. You will need to submit for a permit on the trail you plan to hike to reach the lake. You can find more information about the permitting process here. During peak Summer months you also need to take a shuttle to the trailhead. Since we went at the end of September we were able to park at the trailhead.

Paulina of Little Grunts had permits for the River Trail and invited me along a couple of months before we went in September. I was super excited and immediately jumped on the chance to do this backpacking trip, little did I know the hell I had in store for me.

Thousand Island Lake Trip Report:

My flight to San Francisco was scheduled for Thursday evening and I woke up Thursday morning with a horrible fever and body aches. I had some denial this was happening to me right before a major backpacking trip so I took some Advil and went to work as planned…where I was immediately told to go home. When I got home I laid in bed and tried to decide if I should still fly to San Francisco. About halfway through the day major gastrointestinal distress started to hit and I was getting really worried. I had purchased plane tickets and taken time off work for this trip, it was going to be awful if I couldn’t actually go. So I did what any crazy outdoor person would do, I downed 2x the recommended dose of flu medicine, grabbed my already packed bags, and went to the airport to catch my flight.

After the worlds most miserable flight (thank god it’s only 1.75 hours from Seattle to SF) I arrived at Paulina’s apartment a sweaty flu-ridden mess. I refused to hug her in hopes of avoiding giving her my germs and took some NyQuil and passed out on her couch to prepare for the adventure on Friday evening. On Friday I woke up around noon, took more flu medicine, and declared that, “I AM FINE AND I AM GOING ON THIS TRIP” (I was not fine, I was in a NyQuil/fever delirium and I should not have been allowed to make my own choices). Paulina and I went to pick up some more snacks before everyone in our group showed up and we started the drive to our campsite for the evening, which happened to be a pullout on the side of the road between Yosemite and Mammoth.

Starting out on the River Trail out of Agnew Meadow.

Starting out on the River Trail out of Agnew Meadow.

My fever seemed to have dissipated, but the stomach distress had not. I woke up multiple times in the middle of the night to dig holes as far as possible from fellow campers and take care of business. Luckily there was a full moon and I barely needed to use my headlamp to find my way around in the night. In the morning I woke up to cracked lips, light-headedness and was still battling major queasiness whenever I attempted to eat. Not exactly how you want to feel before hiking into the wilderness overnight, but I was committed at this point. After stopping for breakfast in Mammoth we arrived at the trailhead and I attempted to do my best impression of a healthy human that’s excited to backpack.

Beautiful fall colors on the trail!

Beautiful fall colors on the trail!

The second we started hiking my facade quickly unraveled. I had forgotten the Sierras are at a higher elevation than my usual Cascade Mountain wandering. We started our hike at 9,000 feet and ended around 11,000 feet. The elevation coupled with my stomach issues made this one of the most miserable hikes I have ever been on, and this trail was not that hard. I laugh-cried every time I saw a set of switchbacks because my brain knew they weren’t that bad, but my body felt like I was climbing up Everest and about to die from a lack of oxygen at any moment.

It was a hard hike filled with a lot of silent tears and laying on the ground wondering how much a private helicopter ride to the lake would cost. Around 3pm I finally caught up to everyone at the lake, but if you have camped at Thousand Island Lake before you know you need to continue hiking a little to get to the zone where you are allowed camp. We definitely saw people camping in the no-camping zone, and I doubt they had anywhere near as good of an excuse as I did. The information on where you can camp is on the permit, and posted at the lake. Follow the rules and make sure you are camping in the correct area!

First glimpse of our destination!

First glimpse of our destination!

It was windy the majority of the hike, but it picked up even more when we arrived at the lake. Intense gusts of wind made setting up our tents extremely challenging and I was about ready to burst into tears (again) by the time we finished setting it up. I immediately crawled in for a much needed nap while the rest of our group had a beer and fancy cheese happy hour. After a couple of hours I managed to stumble out of the tent and join them to finish off the last of the cheese.

The face of a not-so-happy-camper finishing off a rind of cheese. Thanks for the photo Paulina!

The face of a not-so-happy-camper finishing off a rind of cheese. Thanks for the photo Paulina!

It was getting closer to sunset so Paulina, Alice, and I changed into our warmer clothes and explored around the lake. We were once again disappointed to see how many people were camping in prohibited areas, some within 50 feet of the water (permits state to camp 100 feet away from the water) and another group camped on the trail. This is a popular lake, please camp in appropriate designated campsites. Your permit will have more information on where you can and cannot camp!

As the sun set, the wind started getting unbearably cold. It took everything in me to stay outside and make our dehydrated meals before crawling into my tent. I almost had a meltdown when my frozen weak hands struggled to open my bear can. I brought my close friend Chelsea on this trip for her first backpacking trip. I convinced her to come with a lot of promises about making her gourmet backcountry meals, cocktails, and carrying the majority of the weight. It’s safe to say that NONE of that happened. (Chelsea, if you are reading this, I am so sorry and I hope you don’t hate backpacking forever after this!) She was a trooper and we at least had a gorgeous sunset! I managed to get a couple of quick shots before putting on every single layer of clothing I had and crawling into my warm sleeping bag.

This is Chelsea. Chelsea is a champion for putting up with me and my false promises on this trip.

This is Chelsea. Chelsea is a champion for putting up with me and my false promises on this trip.

The wind blew our tent into my face for most of the night and I had to get up many times to deal with digestive upsets. Dehydrated backpacking meals in a stomach recovering from the flu didn’t turn out to be a good combo. No worries, I had my trusty trowel, hand sanitizer, and packed out all my toilet paper. Even the stomach flu isn’t a good enough excuse to leave human waste out in the open. When finding rocks to put over my covered cat holes I discovered many piles of human waste/toilet paper that hadn’t been properly buried (aka someone just threw a rock over it) I won’t lie to you, the Sierras are a hard place to properly bury your poo. The ground is rock solid, and most of the time you start digging only to find out it’s solid rock a couple of inches down. Start looking for a place to dig your cat hole the instant you think you might need to go, it will take you longer to find a good place to dig than you think it will! If you have more questions on how to properly dispose of human waste while backpacking the Leave No Trace Center is a great resource!

If I wear sunglasses no one will be able to tell I am dying inside right?

If I wear sunglasses no one will be able to tell I am dying inside right?

We woke up at sunrise with the wind sill bearing down on us. Paulina asked if anyone needed hot water for breakfast, but we were all ready to hike out of there and get back to SF. It was another struggle to take down our tents and pack up in the high wind, but we all managed to pack up quickly. Even with all the late night digestive issues I was starting to feel a lot better and the hike out was no where near as miserable as the hike in, but that may have been because it was mostly downhill.

Sunset over Thousand Island Lake.

Sunset over Thousand Island Lake.

Overall Thousand Island Lake was beautiful, and I really want to try to go back and experience it when I am not dying of the stomach flu and there is less wind! This trip was somewhere right between type two and type three fun for me. I was 100% miserable while I was out there and it seemed very unwise to backpack with the stomach flu. In the end, I am glad I did it though! It would have been a major bummer to fly to San Francisco and miss the trip!

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