Restoring Hetch Hetchy

[ERIC]

A second point is water supply.

A very big +1

There is enough downstream storage for the water.

Source? And one with volumetric numbers accounting for variable water years, please.

[rlown]

A second point is water supply.

A very big +1

There is enough downstream storage for the water.

Source? And one with volumetric numbers accounting for variable water years, please.

Well, the info might be one-sided given it's source, but their plan is shown at http://www.hetchhetchy.org/how/where-wi ... -be-stored" onclick="window.open(this.href);return false;. I think in general, most Californians are very wasteful wrt water..

[87TT]

Sounds like a bad idea to me. Cut off your nose to spite yourface.

[rlown]

figured I'd bump this thread with a pointer to the Condit dam removal project, which just blew up on 10/26/11. Check out the video.. Now, obviously, they wouldn't do such a move on Hetch Hetchy because, well, this is California (read that how you want!).

I was most interested in how they got approval to blow it, given the amount of silt that'll move down stream, but.. Downstream it did move.

http://whitesalmontimelapse.wordpress.com/" onclick="window.open(this.href);return false;

[Ikan Mas]

The northwest is an interesting place to look to for dam removal. Here is a couple of before and after from the Rogue River, my home:
Savage Rapids before:


Savage Rapids after:


Gold Rey before:


Gold Rey after:




Savage Rapids' turbines ran irrigation pumps and shredded salmon. Turned out that it was cheaper to run the irrigation pumps with electricity than water power. Dam came down.

Gold Rey had been out of action since the 70's and was also a fish obtacle. It was probably the last rope pulley generator in the US. I remember seeing it in operation as a teenager. Dam is also down.

[ERIC]

Nice photos Ikan Mas. Cheers for sharing.

[Desert Tortoise]

OK, I will stick out my neck. I LIKE Hetch Hetchy just as it is! I would not like to see it restored. Here is why.

1) The reservoir may not be "natural" but is is stunning. The Sierra has so few large lakes, I think the reservoir is a nice addition. OK, I am a civil engineer - I think the dam is pretty cool too.

2) "Restoring" to "natural conditions" is very unpredictable- hard to say if it will go as planned. The pre-dam conditions were a result of climate and an ecosystem of the 1800's. You do not restore old growth forest. The climate today and near future may well not sustain the kind of revegetation that people are thinking of. You might get a manzanita forest. If you try to put trees back, you may get weak tress (not right rainfall conditions) that are prone to fire and disease.

3) The "bathtub ring". Not sure you can get rid of this. It will be ugly as hell for many years. I remember how the biologists said how wonderful it would be after the Yellowstone Fire. It is 20+ years later now and in my opinion, still ugly.

4) Money- very costly

5) Development. Here is one of my main reasons for not liking the idea of restoration. The upper Tuolumne (Grand Canyon of Tuolumne) is now very protected. Easier access may put undue stress on this. I do not trust that the area will resist development. To take stress of Yosemite Valley, I can see political pressure to add roads, resturants, parking lots, campgrounds etc. The fact that Hetch Hetchy is private and access restricted has helped all the upper watershed remain fairly pristine.

6) It is currently accessable for those with the energy and desire to walk the trails. I could see adding an environmentally safe commercial boat to take sight-seers up the lake.

Just opening the discussion. I guess what I am saying, convince me otherwise. Show me a similar scope restoration that has worked.

For what it's worth there is no bathtub ring along the former shoreline of the old San Franscisquito Rervoir after it's dam burst infamously in the late 1920s. In fact you really have to scrutinize old photos of the dam to figure out where it once stood. Nor is there a bathtub ring along the shore of the long drained Chatsworth Reservoir, another old DWP water storage reservoir drained for reconstruction but never refilled due to seismic hazard considerations that materlized in the aftermath of the 1971 Sylmar Earthquake. Dfferent climates, yes, alpine vs chaparral and very different soils that would likely affect how Hetch Hetchy might look a hundred years after being drained. On the other hand you can still see the old beaches where I live in the Mojave Desert from the big post ice age lakes that filled Indian Wells Valley (now China Lake) and Searls Valley.

[SSSdave]