February 8, 2012 - Bend Bulletin - Siltation fix is upstream
二月 08, 2012
Siltation fix is upstreamPublished: February 08. 2012 4:00AM PST
What to do about the silt in Mirror Pond seems to be a hot topic for discussion, if not action. Here’s my two cents’ worth.
Anyone who has floated the Deschutes River upstream from Bend knows that the river passes through miles of loose soil — volcanic ash? — which is scoured from the banks and carried downstream as silt when river levels fluctuate. The water released into the river below Wickiup Reservoir is totally controlled by the irrigation companies, and varies from almost zero — which devastates trout habitat — to very high levels, which scours great quantities of silt from the erosive banks. That silt is dropped in slow-flowing sections downstream, with a large percentage of it ending up in Mirror Pond, which was formed by the PP&L dam.
There have been attempts to stabilize the loose soil of the river banks by placing and tying down logs on the banks and by planting willows. That kind of treatment should be continued on a larger scale — state and federal agencies would have to be involved. Also, the irrigation companies could better regulate water releases from Wickiup that would reduce the scouring effect on the banks, and incidentally, improve the trout habitat.
To slow future silting of Mirror Pond, look upstream and act there.