Wednesday, January 15, 2020

What Can You Say in 3 Minutes About One of the World's Special Places? Del Puerto Canyon and the Proposed Dam

I was one of a large number of speakers at a forum this evening on the future of a proposed dam at the mouth of Del Puerto Canyon near Patterson, California. I counted roughly 200 people in attendance, and of the 30 or so of the attendees who spoke, none spoke in favor of building the dam (there may have been supporters, but they chose not to speak). What follows is approximately what I said tonight (I had my comments all written out, but I always go off-script!). I've added the pictures to this post (I couldn't use them at the session).
Image may contain: one or more people and people sitting
Statement on the proposed dam and reservoir in Lower Del Puerto Canyon

Thank you for the opportunity to speak to this important issue. My name is Garry Hayes, and I have been a professor of geology at Modesto Junior College for 32 years. I wish to speak to several issues about the canyon and proposed dam.

First, the national significance of Del Puerto Canyon

The Environmental Impact Report is a perfunctory report on the geological resources and hazards at the proposed dam site in Del Puerto Canyon, but fails to communicate the national significance of canyon. Describing Del Puerto as a “typical” canyon of the Coast Ranges is like describing Yosemite as just another glacial valley. If the Diablo Range were under federal ownership, I am convinced that Del Puerto would have warranted consideration as a national monument or national park. Why? It is the only place in Central (and maybe all of) California where one can drive from the earth’s surface into the mantle and do it in an exceedingly scenic manner. One passes through 25,000 feet of marine sediments, through the underlying ocean crust, and into rocks that were once part of the earth’s mantle. At the same time, as others will note, the canyon offers a unique assemblage of endemic plants and animals. It has a rare riparian wetland habitat in an otherwise arid mountain range. I have taken hundreds of students into the canyon for field studies over the last 30 years. The National Association of Geoscience Teachers, the Geological Society of America and other national organizations have conducted tours in the canyon and many geologists have done research there.

It is not widely known, and the EIR fails to mention that the first dinosaur fossils ever found in California were found on a slope just above the inundation zone of the reservoir. I am disturbed that such a significant site would be simply ignored in the planning for this reservoir.
Saurolophus, the species of dinosaur found in Del Puerto Canyon

My other concern about this reservoir involves the instability of the slopes above the proposed reservoir. There are huge and clearly active landslides within the inundation zone. The EIR fails to address the possibilities of large-scale slope failures when the dam is filled. I am concerned about what happens when a slide that formed under arid conditions is subsequently inundated beneath a hundred feet or more of water. I find the statement in the EIR that “the rate of movement of landslides would likely be slow…” to be inadequate and worrisome.

Del Puerto Canyon is a region of national scientific significance, and I am concerned that the EIR does not acknowledge this fact. The backers of the dam have not adequately considered the importance of this important educational locality, and I strongly and sincerely request that the Del Puerto Water District reconsider the Ingram Canyon alternative, given that the Ingram project will not have the detrimental impact that would occur if a dam is built in Del Puerto. We should be increasing educational access to the canyon, not restricting it.

Thank you for your time and attention.
(end of comments)

Del Puerto can use your help! To get involved, there are several things you can do:

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Read the Environmental Impact Report at this link. If Del Puerto Canyon has significance to you, please respond and be active in the opposition! If you have expertise in any of the areas that will affected, you need to be heard from.

There are several important meetings and deadlines coming up very soon:

1/21 6:30pm City Council Meeting. 1 Plaza Circle. - request they take a stand, voice concerns
1/27 5:00pm Public Comments DUE. OR Anthea Hansen PO Box 1596 Patterson CA 95363
1/28 9:00am Board of Supervisors Meeting 1010 10th St Modesto CA - voice concerns, they have final decision

1 comment:

Barry said...

Thanks for providing this valuable information. It's clear that the educational, environmental, historical, recreational and aesthetic values of this canyon far outweigh the taxpayers' subsidies for the profits of corporate agriculture (make no mistake, agriculture will not pay much of the $ costs of this reservoir and dam).
To mortgage the future of a growing city for the profit of corporations under these less-than-favorable geologic conditions is nothing short of immoral. Furthermore, local agriculture is moving wholesale to high-value nut crops that require water every year - in a state that already has much less water than desired. When their crops die for lack of water, they'll come back again to the well, blaming environmentalists and government - but not their greedy selves! That is California's water history, and it needs to stop now! This proposal is immoral, self-deluding and foolish.