Thank you to all of those who attended this year’s annual Henry’s Fork Watershed Council tour! Participants toured the Last Chance Wastewater Treatment Plant, Island Park Reservoir, and Island Park Dam. A special thank you to Fremont County, the City of Island Park, Forsgren Associates, Fall River Rural Electric Cooperative, and Fremont-Madison Irrigation District for sharing their knowledge on some great new projects in our watershed–like the DIRTT Plan and Last Chance WWTP upgrades.
Learn more about the Watershed Council here.
Learn more about the DIRTT Plan here.
Learn more about how Island Park Dam works and how it’s managed.
Learn more about Last Chance WWTP here.
Our Aquatic Ecology Program Manager, Dr. Jack McLaren, joined Idaho Falls city and FIPS-Mouche leadership at the opening ceremony parade along the Snake River Greenbelt to welcome competitors to the watershed and to make sure conservation was front and center.
Drone photo of Island Park Dam taken on September 9, 2026 Looking Back on September September brought lows and highs to Island Park. Island Park Reservoir started September at 29% full and quickly fell to a low of 12% full on September 19. The rapid drawdown of the reservoir was the result of managers needing to move water downstream to American Falls (to irrigate farms in the Magic Valley with senior water rights). Such low
This story was written by Audrey Hunter (2026 intern) and was originally published in the Fall 2026 Newsletter. It’s no secret that late summers on Island Park Reservoir haven’t been in perfect conditions in recent years. Warm, turbid, algae-filled water plague reservoir recreationists while diminishing water quality downstream. Cyclical algal blooms decrease water clarity and create less-than-ideal circumstances for the reservoir’s flora and fauna. What’s the solution? HFF’s DIRTT Plan. In-Reservoir Oxygenation Nutrients released from
Drone photo taken on September 9, 2026 The Henry’s Fork Drought Management Planning Committee met on Wednesday, September 16 2026 to develop an updated reservoir management strategy. Downstream of the Henry’s Fork watershed, lower-valley irrigation demand over the rest of the season is anticipated to be slightly lower than projected last week, so Island Park Reservoir and Grassy Lake (in the Fall River drainage) do not need to deliver any more water out of the
