Cause of malfunction eludes engineers

For a second day, flows from the Afterbay were steady for a long while before slowly rising then suddenly plunging much like yesterday.

Today's river releases weren't exactly steady at 2,000cfs

Today’s river releases weren’t exactly steady at 2,000cfs

There is speculation that a new power line which feeds the Afterbay was energized for the first time and ultimately affected sensitive electronics which help control the gates that regulate releases from Afterbay. Today, one of the gates suddenly closed, and had to be reopened manually. Like yesterday, engineers are scrambling to schedule personnel to man the Afterbay throughout the night to manually make adjustments as needed.

We’ll continue to monitor the situation, and appreciate everyone who has called and/or emailed from the river with visual confirmation of the change in releases. You can monitor activity on the river at

Mysterious bump in flows today

Early this evening at 4:45pm, long time Bighorn outfitter and guide Michael Mastrangelo was working one of his favorite holes with a client when he noticed two extraordinary things: first, that fish were suddenly rising like crazy, and second, that the water was rising up his waders. He didn’t need his years of experience on the river to know that if you’re standing in the same spot and the water is rising when it isn’t supposed to be, something ain’t right. A quick call from the river to his wife Ellyn, and in minutes it was confirmed that the releases from the Afterbay had increased rather dramatically.

        | 16:00 | 1987.73 |
        | 16:15 | 1987.73 |
        | 16:30 | 1861.49 |
        | 16:45 | 2357.82 |
        | 17:00 | 2635.15 |
        | 17:15 | 1998.46 |
        | 17:30 | 1966.38 |
        | 17:45 | 1955.75 |
        | 18:00 | 1977.04 |

The data above is an excerpt of the raw data produced by Reclamation Hydromet system, an online database where stakeholders can monitor river and lake status in near real-time. The time is in military format, and starts at 16:00 which is 4pm. Notice at 4:30pm, the flows took a precipitous drop of over 100cfs, and fifteen minutes later shot up 500cfs to 2,357cfs, and finally peaking at or near 2,635cfs at 5pm. Fifteen minutes later, flows returned to normal at 2,000cfs.

A call to Reclamation yielded few answers, but FOBR will investigate further. In the meantime, a big shout out to Michael and Ellyn for their quick response and thoughtfulness. Watch this site for future updates on this issue and updates to summer releases.

Slight reduction in river releases imminent

During today’s stakeholder conference call with the Bureau of Reclamation and in accordance with the July operating plan, it was suggested that in order to maintain sufficient lake levels and winter river releases, a slight reduction in river releases may be coming in the next few days. Most likely, that reduction will be from 2,000cfs to 1,900cfs.
Reclamation is hoping that a reduction now will allow releases to remain at 1,900cfs for the remainder of the summer barring any unforeseen weather events.
Please monitor this site for the latest information.

Bighorn Lake is full

As expected, Bighorn Lake filled today when it reached the top of the conservation pool at a lake level of 3,640ft. Reclamation engineers are hoping to see the lake continue to fill a bit more in to the exclusive flood pool to help protect winter flows.  Except for some higher elevation snowpack, snow melt runoff is essentially over, and inflows are expected to drop off significantly in the coming days.