Since I've been here, I've learned a lot about the ecological issues facing the local streams and, of course, beautiful Lake Tahoe. Just about every car here has the "Keep Tahoe Blue" sticker on it. I even see them up in Montana every once in a while. While the stickers sell like hotcakes, what is actually being done to protect the lake and its tributaries? Well, take a look...
Upper Truckee River Stream Restoration Project |
I was invited to go on a tour of the Upper Truckee Restoration site yesterday and it was a valuable learning experience. The US Forest Service is preforming a complete stream channel re-construction on a large stretch of the river. Why?
Degraded, eroded, over-widened Upper Truckee River stream channel |
To the untrained eye, this may look like a picturesque meadow stream however, it's really not and there is a lot of stuff going on here which is bad for the stream and Lake Tahoe.
The Upper Truckee's banks are badly eroded and getting worse as you can see in the picture. They are so badly eroded that even the bank vegetation that currently exists is falling into the river.
The stream is also incised, meaning that is has eroded itself into a deep channel which is completely separated from its floodplain. The Upper Truckee has lost its ability to naturally overflow out into the meadow around it. This is important for dispersing energy during high flows, filtering the water before it goes into the lake, and creating riparian habitat adjacent to the stream.
The stream is also over-widened meaning that during low flows, the river is shallow and warms easily. Not good for our trout friends!
At this point, the Upper Truckee is the largest non-point source of sediment and nutrients to Lake Tahoe. Reconnecting the stream to the floodplain and the resulting filtering processes are a vital part of "Keeping Tahoe Blue."
US Forest Service employees getting a tour of the project site |
So, what went wrong? How did the river get so F-ed up?
Well, it's all of the usual culprits. Urbanization, historic uses, intensive bank-side grazing, upstream bank stabilization, etc, etc, etc.
Roughing in the new channel |
Heavily engineered stream channel construction in process |
New stream bed in recently completed section |
Willow growing from planted willow cuttings |
This reach was completed only a year ago and the willows are starting to go nuts |
Like a lot of restoration projects, this one has some political contention. I understand that most people don't really get stream geomorphology, hydrology, and ecology and the idea of rebuilding a section of stream when the old one is perceived to be "just fine" is a major hurdle for all restoration projects. Communicating these concepts to the public in a way that is effective and understandable is one of the hardest aspects of restoration. In this case, the USFS is doing a pretty good job.
If you have any qualms about this project, go learn about it. They have about 3 field trips like this a week and you can bring up any concerns and questions you might have. While it may not change your mind, you'll at least know more about the project and the thought process behind it. This project also went through a massive public comment period and has more bureaucratic restraints than I have ever seen on a project like this.
Get involved - don't just put a sticker on your car!
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