Connecting Bighorn Observations to Facts
By Anne Marie Emery, Executive director
Working in conservation, one is constantly struggling with finding numerical data that correlates and supports angler observations regarding the health of the river. Not a day goes by that I am not reminded by seasoned anglers, who have fishing the Bighorn since it became a state public resource, that the river, while still one of the most successful tailwater fisheries in the world, is not the same as it was twenty, or even thirty years ago. I often leave these conversations feeling envious of the “good old days,” but more importantly, I leave feeling a bit more educated on what myself, and the Alliance are working to restore the fishery to- not only for ourselves, but for our children.
That being said, tailwater fisheries change. Some of these changes are unavoidable byproducts of dam construction that in turn, change the rate of sediment delivery and alter natural flow regimes. Famed rivers such as the Bighorn and the Henry’s Fork have experienced these changes through the loss of instream islands and channel complexity as the river becomes starved of sediment that is now contained behind dams.
Yet these changes are also exasperated and accelerated with high sustained flows that can be a result of Mother Nature, a result of overly conservative water storage management practices, or both. The main complaint I hear from anglers of the Bighorn is that flow releases and water management of those flows has changed over the years. Analyzing the data, they are absolutely correct. Over the past nine years, the Bighorn has experienced more days with flows exceeding 8,000cfs than the prior 40 years combined.
High flows, especially high sustained flows, can negatively affect the Bighorn over the years, perhaps not in the number of fish caught, but by affecting the health of the river environment that wild trout depend on -which can start affecting fish populations down the road- and by affecting angler opportunities to recreate. This year the Alliance was inundated with concerned calls regarding higher than normal river temperatures, concerns over the number of fish caught with symptoms of nitrogen gas supersaturation, reduced or premature aquatic insect hatches, reduced water clarity and inaccessible boat ramps which were not constructed to handle high flows. Most recently I was sent a picture of a 27″ brown trout that was as skinny an eel- the poster child for surviving an entire season of Bighorn high flows.
According to the Bureau of Reclamation (BOR) the agency “has seen highly variable runoff years ranging from a record year of 2011 (and now 2017), to the much below average runoff years in 2012 and 2013″ and that “the high variability of these runoff years and the high variability of conditions within each year makes for very challenging operational conditions.” The federal agency also points out that while river flows are high the dam is still doing its job by preventing even higher flows that would occur without the placement of the dam.
The fact that 2017 was a record water year for the Bighorn is inarguable. Some state that Mother Nature signed the orders, and overly conservative water storage management practices delivered the impact to the river. Some say that BOR did the best that they could considering their inability to forecast precipitation and runoff timing and are grateful that the outcome was not worse. I say that extreme high water and sometimes extreme low water years happen, and if they act as isolated incidents, the river will recover. However, outside of the historic 2017 water year, data shows that since 2008, the Bighorn has consistently (with the exception of years 2012 & 2013) experienced the pressure of high flow releases. When high flow events, or low flow events become the norm as opposed to the exception below a dam- we have a water management problem. When a decade goes by without changes being made to address or correct overly conservative water management protocols, we have an environmental injustice and a political issue.
Today, we are already in water year 2018 and the reservoir is 99.1% full with current river releases hovering around the 5000cfs mark – just 264cfs over the inflow that is entering the reservoir. These numbers bring mixed feelings. While the Alliance is hopeful that a full reservoir will result in higher than average winter flow releases that will benefit the over-wintering survival and recruitment of age 0 class wild trout, we remain worried that BOR will again be overly conservative with their winter flow releases and that will result in inadequate storage availability come the Spring. Next month, we will be participating in the Bighorn River Issues group meeting Billings where we will be presented with a review of the last water year, and informed of BOR’s water plan moving forward. After months of meetings with the National Park Service, Montana Fish Wildlife and Parks, and the BOR, the Alliance is adamantly expecting change- and is preparing to take action on the meetings outcome. Stay tuned.