Middle Fork of the Salmon vs Main Salmon

Middle Fork of the Salmon versus the Main Salmon. Here’s a look at both, by the numbers, with further explanation below.

Mileage

The Middle Fork from Boundary Creek to Cache Bar is just under 100 miles. The Main Salmon begins just a few miles after the Middle Fork takeout at Corn Creek and runs 81 miles to Carey Creek. However, at lower water levels on the Middle Fork, trips often start by flying into Indian Creek, which shaves off approximately 25 miles from the upper section, resulting in a roughly 75-mile trip

Length of trip

The length of the trip is related to the mileage. Most groups spend 5 to 6 days on the Main Salmon. The Middle Fork has a larger range, but 6 to 7 days is normal.

Difficulty

The Middle Fork of the Salmon has rapids that are Class II, III and IV at most flows, whereas the Main Salmon, at most flows, is Class II and III. However, like other rivers, the degree of difficulty significantly changes based on water level. Both rivers are difficult at high flows and require you to be excellent at reading water and maneuvering a raft.

Quantity of rapids

The MFS has more rapids than the Main. This is because the Main Salmon is a pool-drop river, meaning there is a long calm pool between the rapids, whereas the Middle Fork tends to be more continuous. Additionally, towards the end of the trip, the Main Salmon enters a calm section of the canyon, known as The Lake. While the river isn’t actually entering a lake or reservoir, there are significantly fewer rapids or gradient for 20 miles.

River volume

The Main Salmon is a high-volume river, and the rapids and characteristics of the river reflect that. Rapids tend to have splashy waves and not many rocks. The waves make it fun, especially on hot days. If you jump out and swim, the odds are you won’t be able to feel the river bottom (not that you should since you shouldn’t be standing). The Middle Fork of the Salmon is mostly the opposite. Towards the beginning of the trip, the river gradient is steeper, so there is current stacked between the rapids meaning you don’t get much of a break if you’re on the oars. The river is low volume so it can be shallow meaning you will be spending a lot of time rowing away from rocks or if it’s later in the season, getting your raft stuck on rocks and then pushing off of them. As you continue downstream, the Middle Fork picks up numerous side creeks and tributaries, eventually adding to the river volume to the point where it’s hard to believe it’s the same river you started on five days ago.

Permit odds

It’s difficult to win a permit on either river. Both are part of the 4-Rivers Lottery which is the Main Salmon, Middle Fork of the Salmon, Hells Canyon, and the Selway. The permit odds were calculated by dividing the number of applicants by the available permits. While this is a simplified approach, it effectively illustrates the generally low probability of securing a permit for either river Here is a link to the USFS PDF.

Water temperature

This is also one of those categories that depends on when you go. If you go peak summer (July, August) then the water temperature on the Main Salmon is warmer than the Middle Fork of the Salmon. How warm is it? We have a blogpost dedicated to Main Salmon river temperatures here. It averages 67 degrees in July and August. Still chilly, but easy enough to swim in and enjoy. The Middle Fork of the Salmon doesn’t have any gauges measuring water temperature, but it is cooler (maybe not by much in July and August) than the Main.

River beaches

Some people love beach camping, others don’t care for it. The division is usually based on age. The Main Salmon has tons of beach camping and it gets really good towards the end of the trip. Kids love this. The Middle Fork has far fewer beaches and they are all located in Impassable Canyon. Elk Bar and Otter Bar are the two that come to mind.

Hot Springs

If you ask anyone what makes the Middle Fork of the Salmon so cool, hot springs will be near the top of the list. There are a lot of hot springs on the Middle Fork. Some of them are small pools, big enough for a couple of people to sit in, others are larger, like Loon Creek hot springs which can fit many people and is situated alongside a beautiful creek. Not to be outdone, the Main Salmon has one of the best hot springs in Idaho, but it has only one.

Fishing

The Middle Fork of the Salmon has good fishing. Especially so in September when temperatures cool down. President Carter famously caught 59 trout in a single day on the Middle Fork in 1978. The fishing on the Main Salmon isn’t nearly as good. If you know what you’re doing, you’ll catch some fish, but if you’re a beginner, you’ll be doing a lot of casting. The exception to this on the Main, is the side creeks. I’ve had good luck fishing these confluences.

Hiking

There’s a trail that follows the Middle Fork of the Salmon from Boundary Creek all the way to Big Creek, the start of Impassable Canyon. So technically, there is a hiking opportunity at most camps. That doesn’t necessarily mean the hiking is fantastic at every camp, but it’s available. (Hard to beat hiking along a river though.) Additionally, you have trails that shoot up drainages such as Big Creek, Loon Creek and Camas Creek, for example, which adds variety. The Main Salmon, on the other hand, has some hiking up drainages, the most popular being the South Fork of the Salmon or Indian Creek, but it doesn’t have a river trail that follows it for the majority of the river. My asterisk to this is that even though there aren’t as many trail opportunities, that doesn’t mean you can’t hike and explore the area where your camp is located. We used to hike all over the Main Salmon, we would pick out a good viewpoint and simply hike to it.

Jet boats

Jet boats aren’t allowed on the Middle Fork, while there are some jet boats on the Main. You’ll encounter more jet boats as you float downstream on the Main, but it’s not like Hells Canyon or the Lower Salmon which see a lot of jet boat activity.

Backcountry air traffic

The Middle Fork of the Salmon sees more backcountry air traffic than the Main Salmon. When the water gets low, many commercial and private groups opt to fly into Indian Creek or Thomas Creek on the Middle Fork of the Salmon. Due to the Main Salmon always having enough water, there is no need to fly in. Additionally, there are far fewer public airstrips on the Main, just one, in fact.

Conclusion

If you like relatively easy rafting with splashy rapids, beach camping and / or there are kids in the group – the Main Salmon is a great option. If you’re into fishing, hiking, lots of rapids, and hot springs, the Middle Fork of the Salmon is awesome. And if you are supremely lucky – extraordinarily lucky – you can try to win a Middle Fork of the Salmon to Main Salmon combo permit and see both on the same trip.