Savery Creek looked at again as silting, widening, temperature become fish habitat issues
The High Savery Dam and Reservoir, according to Brad Tribby, Fishery Biologist for the Bureau of Land Management (BLM), has always had good intentions for the region. It supplies irrigation for countless agricultural properties in the lower end of the tributaries and that, in turn, supports economic development. However, its execution resulted in some environmental issues that multiple stakeholders in the region have been now tackling.
Tribby explained that on the lower side of the dam, on Savery Creek, there has been severe river degradation that not only impacts the health of the system, but also impacts wildlife.
"When clear water is released from a dam, the water is really hungry for sediment, so it erodes banks easier. And I think that combined with a very different hydrograph in the system, that the system is not used to, has really created some stream degradation issues."
The different hydrograph Tribby is referring to, are weirs that were added along the creek to encourage restoration and promote wetlands; which, was one of the prescriptions used when constructing the dam. Some of the weirs have ultimately widened the stream channel, promoting more extensive bank cutting.
"At the same time, part of their 404 [permit needed to construct dam] was that they had to put some huge grade control structures in (weirs). They are 150 feet wide and they are made of steel and are literally put in the stream... It prevents down cutting, it'll raise your water table for things like wetlands if you are trying to re-establish willow communities," Tribby said. "I don't know if they were just not necessary here or if they're just too big or there is too many of them but basically it's created some huge issues."
These prescriptions contributed to sediment being picked up on the creek and deposited on the point bar, which is the side where normally sediment deposition occurs. However, due to excessive bank erosion, the amount of fine sediment depositing is much higher than it should be. This impacts trout habitat on a creek.
According to Tribby, when trout spawn, the female digs a pit to create her nest and place her eggs. This allows for the eggs to be located in between crevassed rocks where water flows by and is oxygenating the eggs. Therefore, if there is a high level of fine sediment building up in these locations, oxygen does not get to the eggs and they die.
In addition, the dam itself has posed some problems for the trout downstream in terms of the temperature of the water. According to Tribby, on most of channels that trout occupy in the region, they are most stressed during the later summer months when there is less water and the temperature heats up - resulting in fishing closures on some stretches of water.
This is happening on Savery Creek, but not at a standard time. The dam releases water during the late summer because there is less water available for agricultural purposes. So, in the early summer, when the reservoir is filling up, there is minimal water flowing down the creek.
"These are the times when the fish get really stressed," said Tribby. "That same situation is happening in reverse."
Although there are more large scope issues that will take some time to remedy, Tribby, along with many others, has been working on a way to kickstart improvements by doing what they know they can. Recently, he has been working with stakeholders to establish an Adopt-A-Trout program with Baggs School to ultimately collect baseline data on how the trout are coping in the ever-changing conditions along the stream.
"Part of the Adopt-A-Trout mission is half education and half making sure you are doing it on systems where we need scientific data on," Tribby said. "This was a great string for that because I wanted fish movement data on Savery Creek."
Tribby also mentions that the partners involved in this specific Adopt-A-Trout program are what make the monitoring so successful. Partners include Trout Unlimited, BLM, Wyoming Game and Fish and the Little Snake River Conservation District.
Baggs School has been involved with their Adopt-A-Trout program along the creek, where they aid in collecting data for radio tags that are put on trout. This enables stakeholders such as Tribby to see the impacts that the construction of the dam has had on trout. In addition, it's getting students out in the field, where they gain first-hand experience and accountability towards the project.
"I'm going to take the high school kids out and we are going to literally go and track fish. Instead of just learning about radio telemetry, they are going to go out and do it," said Tribby.
Tribby is excited for programs such as these and is very curious about what kind of baseline data he will receive.
"I think what we are going to see is how important Savery Creek is as a tributary to the Little Snake River in terms of spawning."
This is a piece of the puzzle that will ultimately aid in understanding how the trout are doing in reaction to the river degradation issues and what is the best way to go about restoration efforts.
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