SOUTH FORK BOISE RIVER FLOW UPDATE

southforkboise:

Today the flows at Anderson Ranch Dam were decreased by 200 cfs to the summer “normal” flow of 1,600 cfs (first graph).  The salmon flow augmentation releases concluded July 15.

The drop to 1,600 cfs comes about one month earlier than it did last year.  The second graph displays this year’s flow in blue, last year in green and the average in red.  The blue line has been riding on top of the green line most of July, until today with the drop on this graph, to the level seen in mid August 2009 depicted on the green line.

As far as water contents in Anderson Ranch reservoir are concerned, this year has been tracking with 2009 as seen in the third graph, but these lines should soon depart and the blue line will drop less steeply.  If we go one month with 200 cfs less being released, and the flow releases stay the same through the fall, it means an extra 12,000 acre feet in Anderson as we approach winter.  This amount of water means more in a pool that starts off with 220,000 acre feet and is trying to fill to 400,000 acre feet.  If the pool is completely empty the 12,000 acre feet means less on a percentage basis.

Finally, the lasts graph shows the total reservoir contents in the Boise River system this year as compared to last year and the long term average.  The water volume is tracking very close to last year.  The drop in 200 cfs in Anderson may not mean as much at the level of a reservoir system that can store one million acre feet.

The implications for next year are unknown since we are very much a snow dependent reservoir system, but any extra amount going into the winter is always welcome.

New Bridge at Feather River Restores Fish Passage

The Mountain Home Highway District recently completed a new bridge over the Feather River, replacing the old multi culvert crossing, and the project results in more than fifty miles of habitat reconnected to the upper South Fork Boise River.

The project is a result of cooperation with the Boise National Forest and the Federal Highway Administration.   A program called the Federal Highways Transportation for Aquatic Passage was the source of funding for removing the triple culvert and putting in a new bridge.  Nearly 55 miles of stream habitat in the Feather River now is reconnected to the upper South Fork Boise River, providing fish access to headwaters in an important tributary.  An isolated bull trout population will also benefit from the free passage in the stream.

This is a great project for our fisheries in southwest Idaho and Trout Unlimited congratulates the Mountain Home Highway District, Boise National Forest and the Federal Highway Administration for taking on this project.

Chinook salmon in the Boise River.

TROUT UNLIMITED ANNUAL STREAM CLEAN-UP DAY

Join in the second annual Trout Unlimited National Stream Clean-up Day.

Our event will be Saturday, June 26, on the South Fork Boise River.

The plan is to meet at the Reclamation Village at 10:00 a.m. 

Our focus this year will be on invasive species, weeds and aquatic invasive species that could impact the South Fork Boise River. We will be joined by the Idaho State Department of Agriculture and learn about invasive species.

Please RSVP with Pam Elkovich at 345-9800 or pelkovich@tu.org so we know how many people will be attending. We will provide a lunch.

In addition, Trout Unlimited will be taking veterans fly fishing on the 26th. We are still looking for some additional boats, boat operators and other volunteers who can take a veteran fly fishing. Please contact Richard Jones at 853-7788 if you are interested in helping.

With the Boise River flows decreasing Friday evening was an appropriate time to go inspect two project sites and see how they did with the unexpected high water.

The first four photos show the south bank revegetation project near Bown Crossing.  The willow cuttings are still largely submerged but came through just fine.  The top soil that capped the section of bank was washed away as were about half of the cottonwood trees.  But many of the trees remain and had secured roots into the bank in the weeks prior to the high water releases.

The second set of photos is at the Heron Creek outlet next to the Boise River.  A beaver was visiting the project site and munching some cottonwood and willow branches.  In the background of the first photo is a splash from a rising trout!

Looking across Heron Creek from the opposite side the beaver was undisturbed by the ducks that went swimming by.  Meanwhile the final set of photos show the willow that was planted last July is continuing to grow and it will no doubt benefit from the high water that provides water to the roots.