Wouldn’t ya’ know it – we’d be off fishing when the story broke yesterday. 

The story goes that a fisherman near Hebgen dam on Sunday afternoon heard a loud pop and “a strange sucking sound”, and immediately noted a “frothing” in the water near the headgates of the intake tower. 

The first to inspect the dam were apparently Madison County Undersheriff Roger Thompson and Steve Covas, PPL supervisor of the Madison Dam at Ennis. A 175-pound manhole cover had been blown off and was lying about 6 feet away.  They went on to explain that the timber and concrete intake structure, 75 feet tall in all and mostly underwater, has four intake gates – two of which are typically operative at a time.  Thompson and Covas could see water churning through the two chambers that should have been empty and surmised that an underwater breach had occurred. 

Dam outflows that had been running in the neighborhood of 850 cfs (and in fact were a source of controversy in the weeks prior) suddenly jumped to around 3500 cfs. 

The situation, probably fueled by the threat of a possibly significant fall rain system, prompted the evacuation of the river and campgrounds from Hebgen to Quake, and then shortly thereafter on down to Ennis. 

As can happen when word of mouth takes off like a prairie fire in eastern Montana, rumors circulated that Ennis would flood and folks became somewhat animated.  Volunteers were eventually dispatched to quell rumors in Ennis, and a community meeting was called at about 2300 on Sunday, drawing nearly 100 folks. 

As an aside, sources have estimated as this event has been discussed in the news that Ennis would have anywhere from eight to nine and a half hours warning if there was a catastrophic dam failure. 

A federal inspector was due at the dam last night, and PPL has apparently engaged the Washington Group of Missoula to install a 17 foot wide steel bulkhead to plug the unrestrained outflow.  Rumors abound as to the timing and makeup of the repair; some have suggested the newly fabricated bulkhead gate could be placed at first light today, though several news sources have quoted engineers as having some concern that placement of the metal gate could cause more damage. 

This morning flows are still zooming on the river – at the upper river gage near Grayling flows were 3310 cfs at 0400 this morning (the most current reading), 3680 cfs at Kirby at 0645, and as you might expect they’ve significantly bumped flows on the Lower Madison out of Ennis lake from 1500 to 3150 cfs (0645). 

Everyone’s been pushing for a bit more water in the river – this is much, much more than anyone bargained for.  We’ll follow the story along and try and put together some sensible thoughts about fishing impacts once the flows have been constrained. 

Photo credit - Bozeman Daily Chronicle; we’ll head up there most likely late morning and see what we can film or get a picture of. 

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