About
Being from Idaho Falls, I have been to Island Park Dam a few times.
The area is located about 38 miles from Ashton, which is the closest larger city, and it is on Henry’s Fork. And with the property sitting right on the water, it’s truly an impressive sight.
The dam itself is over 90 feet high and is called a zoned earth-fill structure. It was built to provide water to the nearby areas and residents. In fact, the water here in Island Park and the Grassy Lake Reservoirs meets the needs of people in both Madison and Fremont Counties.
With a bit of history, the dam has been an important part of the community for some time.
In the early 1990s, a powerplant was built on it (it was privately owned), and that remained for some time. Then, in the 2000s, I found out that they installed a one-foot inflatable rubber dam. This was positioned on the spillway crest with the goal of providing better control of the surcharge that was created in these areas.
You cannot really tour the Island Park Dam, but you can explore the Island Park Reservoir. And it is easy to see the dam when you do. There are actually boat ramps and camping areas in this area for those who want to check it out.
Fun Facts About Island Park Dam
I did some research to get a better idea of what the Island Park Dam really is, and my mind was blown.
It holds a total of 135,500 acres as total storage capacity. And while the area does not use that much, they use most of it. It was built from 1937 through 1939 with the goal of creating irrigation options for the Idaho Snake River Plain.
The building of the dam was pretty important to the region not just because of the actual water needs but also provided jobs to a lot of the people in the area who were being negatively impacted by the Great Depression.
There have been some issues with the dam over time, including some massive renovations to it in the 1980s, but otherwise, it has held up well throughout the years. This work included removing and replacing the concrete that was falling apart here onto the spillway. They also had to shore up other areas.
The Upper Snake Field Office owns the dam today. It is operated by the Fremont and Madison Irrigation District.
Getting There
Island Park Dam is just off I-20. It is a historical landmark with signs everywhere that tell you where to go. You will find it right on the banks of Crow Creek.
Local Tips
- One of the reasons I booked my most recent trip was to do some fishing, and there are some great spots near the dam to do that. You can rent a boat nearby or bring your own to head into the water for a long day of fishing for trout and more.
- It can be mesmerizing just to watch and listen to the dam. Take some photos of it spilling over.
- If you visit the reservoir during the early morning hours, you will likely see a lot of animals in the area, including elk and bison coming in to have a drink.
- The hydroelectric power produced by the dam and the power plant is one of the cleanest sources of energy, which makes it a very fitting option for its location at Yellowstone National Park.