07 July 2008

Silver Bow Creek Float II: In the Hot Zone

A week or so ago, I floated the upper reach of Silver Bow Creek from Butte to Ramsay ("Superfund Recreation"). I had intended to float through Durant Canyon, but that trip was abbreviated when my inflatable "Tahiti boat" suffered a small tear that deflated the floor. Once again, here is a map of the area:

Sunday, I resumed the trip, putting in at Miles Crossing just west of Ramsay. This area is still "hot"--that is, it is still contaminated with arsenic and heavy metals from more than a century of mining and smelting upstream at Butte, Montana. While I did not exactly hold my breath going through this area, I did minimize my contact with the water and avoid contact with the obviously contaminated streambanks.

Here is an area where tailings are currently being removed (i.e. remedy):

And a new stream bed is under construction (remedy & restoration combined):

This area is just above the Miles Crossing bridge where RTD and I put-in:

What a contrast, this barren riparian zone compared with the lush riparian zone in the reach I floated last week:

The barren areas are caused by the heavy metals and the resulting phytotoxicity. Many of these tailings were originally deposited high on the flood plain during the 1908 flood, but constant erosion and re-deposition have spread them throughout the current floodplain:

Still, it's a pretty place. As one enters Durant Canyon, one forgets they are in the midst of America's largest Superfund site:

About midway through, the cold and relatively clean waters of German Gulch Creek join Silver Bow Creek:

I say "relatively clean," because although German Gulch supports a good population of native westslope cutthroat trout, that population is threatened by selenium contamination bleeding from the abandoned Beal Mountain Mine. Here's nice little westslope cutthroat from German Gulch:

If you fish there, please don't kill any. There aren't many populations like this left, and we need them to repopulate Silver Bow Creek some day in the future when it's clean enough to support trout.
Here's the view to a sheer volcanic outcrop directly across from where German Gulch Creek enters:

A redtailed hawk put on a show for us as we ate lunch and lay down for a quick nap:

The Durant Canyon section has some pretty good waves and one ledge-waterfall drop of about four feet immediately below the German Gulch confluence. That was exciting. I also rubbed on a few rocks, and would recommend that flows be 50 to 60 cfs according to the upper Silver Bow Creek hydrograph, instead of the 40 cfs that I floated on.

As the lower canyon opens up to the Gregson/Crackerville flood plain, the stark reality of Superfund scenery really sets in. I suppose this is because the swift waters of the canyon move polluted sediments through fairly effectively, whereas they are deposited as the floodplain spreads out and water velocity slows.

Here you can see the layers of toxic tailing laid down by high water years ago. The bluish-green deposits on the left side are probably rich in copper salts:

Here's an even more graphic tailings deposit showing copper salts:

And here's a "ghost forest" of trees killed by those arsenic and heavy metals-laden deposits:

And -- end of the line -- here's RTD at the outlet of a small impoundment near our takeout point where Silver Bow Creek crosses the Gregson/Fairmont Road (both she & I got bath last night!):

No comments: