LaPrele Dam emerges as poster child for Wyoming’s ‘aging irrigation infrastructure’
The state's recent order to demolish the beleaguered 115-year-old LaPrele Dam has drawn renewed attention to Wyoming's aging water infrastructure. A legislative panel will discuss funding for improvements, as well as public involvement in demolition orders.
The Select Water Committee is meeting Wednesday and Thursday in Casper to discuss potential funding strategies for hundreds of millions of dollars in ongoing water development projects, including how to shore up more than $118 million to replace the LaPrele Dam, which is under an immediate demolition order to avoid a potential "catastrophic failure."
"The state has a ton of aging irrigation infrastructure," Converse County Commission Chairman Jim Willox said. "The LaPrele Dam is just one of the biggest and most recent."
State Engineer Brandon Gebhart earlier this month issued an order to immediately breach the LaPrele dam after new cracks were discovered near the structure's outlet, noting that such Ambursen-style dams have the potential to crumble under water pressure rather than gradually give way in the event of a failure.
At full capacity, water would "run over the top of [Interstate 25]. It puts 30 feet of water on [Ayres] Natural Bridge. It's a significant event," Willox said.
Such a catastrophic event has been mitigated, for now, according to state officials, by draining the reservoir behind the dam earlier this fall. The state is now in a rush to demolish the dam by April — at least to the point where it will allow runoff to pass freely without backing up.
So far, the state has set aside $30 million and has secured a $32 million grant from the federal Infrastructure Investment and Jobs Act for LaPrele's demolition and replacement. The state hopes to win another $68 million in federal dollars as officials continue to discuss how to fully fund the project, according to state officials.
More oversight in breach orders?
The committee will also consider draft legislation to require more input from affected irrigators and the public when issuing a breach order.
The draft bill entitled Breach orders due process, would require "the state engineer to hold public meetings, provide notice," and require "approval by water rights holders or landowners with a storage right before the state engineer can issue an emergency order to breach a dam or diversion."
The legislation would not retroactively impact the state engineer's order regarding the LaPrele Dam.
It's unclear whether there's been a formal challenge to the state engineer's breach order regarding the LaPrele dam. Though the LaPrele Irrigation District has issued statements acknowledging the need to immediately address the threat the dam poses, they are certain to suffer from having less irrigation water, Willox said, until a new dam is completed — tentatively in 2029.
Willox explained that the original plan to replace the dam would have allowed for some minimal storage for limited late-season delivery. Now, the 100 or so irrigators reliant on LaPrele Creek water are forced to forego any water storage until a new dam is completed.
The irrigation district is discussing how to allocate any late-season water that Mother Nature delivers, according to Willox.
"There's just a lot of irrigation infrastructure in the state that was developed decades ago, so I think the [Select] Water Committee is going to talk about, generically, is that we've got a lot of aging infrastructure," Wilcox said.
