Section “A” of the Green River in Utah begins as the river flows below Flaming Gorge Dam. Flaming Gorge Dam is located on the Green River just south of the border with Wyoming and the reservoir itself actually straddles the state border. Half of the reservoir is in Utah and half is located in Wyoming.
The river below the dam flows at relatively consistent temperature as a result of selective withdrawal structures built into the dam. These structures allow water to be taken from various levels depending on the temperature so that optimum temperatures for trout growth is maintained. Even though this is possible, it isn’t practical to constantly change this so there are times when it is colder than it could be but in general it is maintained optimally for the trout.
This section of the river is crystal clear most of the time. There are only two exceptions to this:
- When the spring runoff is at its peak and some of the runoff water makes its way through the reservoir.
- When a large rainstorm drops enough precipitation to fill the runoff creeks thereby muddying the river.
The Green River in this section is in a very deep canyon and is comprised of deep pools with rapids and pocketwater in between. There are some riffles and shallow runs as well, but it is fairly consistent deep pools and backeddies followed by runs into tailouts. Much of the water where the fish hang out is actually quite close to the bank. This is due both to the character of the river, but also to the habits of the dominant species, Brown Trout.
The upper half of the A section is deeper in the gorge and as you progress down river the canyon gradually opens up. The lower half of A section has a lot more rocky, pocketwater and riffles as this occurs.
The population of trout on this section is very high at one point over 20,000 (per linear mile) in the first mile below the dam and 10,000 per mile after that and 7,000 fish per square mile average. Truly amazing numbers of trout! Current numbers put these figures lower but still at very impressive levels. The population of fish in this section of the Green River is dominated by brown trout although there are decent numbers of rainbow trout as well in addition to some cutthroat trout and the rare brook trout. Like many western rivers, there are of course mountain whitefish and also carp, suckers and various other non game species.