Commenting on last week’s ruling by a San Francisco federal judge that work on the Willits Bypass can proceed despite legal objections from environmentalists and the Farm Bureau that the Bypass is bad every which way, Caltrans District 1 Director Charlie Fielder said, “We are pleased with the ruling. Our extensive mitigation plans not only preserve native species and improve the quality of the watershed in the Little Lake Valley, they will also greatly increase the overall quality of fisheries in these headwaters of the Eel River.”
Fielder noted that Caltrans mitigation plans include removing culverts on Haehl and Upp Creeks to open up the headwaters sections of these creeks to spawning fish. Installation of natural bottom culverts on Ryan Creek will allow summering juvenile Southern Oregon-Northern California Coho salmon, a species designated as threatened, to seek summer rearing habitat and greatly increase the species' chances for long-term survival. Fencing will be installed along all of the creeks to keep cattle out of the creeks and riparian zones, increasing water quality and fisheries habitat.
With the fish taken care of, the large loss of farmland dealt with, and the pesky last-minute lawsuit out of the way, Caltrans and their contractors, Dublin-based DeSilva-Gates Construction, and Utah-based Flatiron West Inc., can proceed with the bypass, which Caltrans says “is designed to relieve congestion, reduce delays, and improve safety for traffic and pedestrians along Highway 101 through Willits.”
The nine-plus mile Bypass is currently estimated to cost about $210 million, some $136 million of which will come from Proposition 1B (2006) highway improvement bond funds.
Last February we pointed out that the unique geology of Little Lake Valley will present major challenges to construction.
According to Humboldt State Geologist Adam C. Woolace, “Little Lake Valley (town site of Willits) is an intermontane [between mountains] basin within the northern California Coast Ranges that contains a record of basin sedimentation and deformation during the Pleistocene. (Little Lake Valley is remarkable [my emphasis] because it is a basin containing a thick section of Quaternary to upper Neogene sediment situated at a major drainage divide between the north-flowing Eel River and the south-flowing Russian River. Well logs indicate that Quaternary and upper Neogene sediment fills the valley to depths greater than 140 meters [460 feet]…)”
Meaning the Bypass will be anchored in what amounts to a gravel pit 500 feet deep, not to mention on an earthquake fault line.
Woolace adds, “Quaternary and upper Neogene sediment fills the valley to depths greater than 140 meters.” And, “Valley fill mainly consists of fine grained lacustrine and overbank sediment and coarser grained gravel alluvium…”
In plain English, that's several hundred feet or more of, basically, sediment. Little Lake Valley is full of the geological equivalent of fine and course silt and relatively loose sediment that have accumulated in the basin over the eons.
None of this is news to anyone who has lived in Willits for any length of time. Nor is it news to Caltrans because, among other things, Caltrans has engaged in almost continuous highway repairs, bank stabilization and reconstruction on the Willits Grade south of Willits off and on for many years where slides and slipouts are common.
Caltrans' own assessment of the Little Lake Valley geology, as contained in the voluminous Bypass planning documents admits that, “Overall, [the selected route of the Willits Bypass project] appears to have the fewest geotechnical challenges.” Meaning that all the options considered had serious “geological challenges,” but Caltrans picked the one with the “fewest.”
Excerpts from Caltrans's District Geotechnical Design Report For Willits Bypass (Phase 1) are revealing:
“… settlement will be significant for portions of the project. The immediate settlement is expected to occur during the loading process, the primary settlement will occur during the loading and settlement waiting period, and secondary settlement is expected to occur for many years after construction is complete. … As shown, the calculated time required to achieve 90% primary consolidation varies significantly from 30 to 3600 days [one month to almost ten years!]. These variances are dependant upon the thickness of soft soil layers, their properties, and fill heights. … Based on past experiences, settlement may [!] occur more rapidly than calculated due to sand lenses and organic fibers within the clay..."
“Dense to very dense sand (or silt)” is still sand or silt.
The state geologist who did the backup paperwork seems to recognize that there will be settlement and that things “should” be done about it.
Unfortunately, when you’re talking about government contracts awarded to the Low Bidder, “shoulds” usually become “can’t affords.”
The Willits bypass includes about three miles of elevated viaduct. But the geological report doesn't specifically address the geology of the ground under the elevated viaduct segment where, of course, the most settlement can be expected to occur.
There’s no specific mention of the pylons and how much settlement can be expected beneath them, even though that’s where the most settlement will occur. The geological report seems to assume that the settlement will only occur because the pavement will be placed over the loose silt, which will then “settle.”
Summary: the project will built on “hard fat clay” … “elastic silt” … “dense to very dense sand” (which sounds like an oxymoron to the casual reader) … “clayey sand” … “and silt” which will require “long-term maintenance.”
It’s far from clear how the geologist calculated the amount of settlement they estimate or how long it will take — give or take 50 years — since Little Lake Valley is a geologically unique area and core samples and borings themselves won't tell you how much weight can be supported by the sand underneath the pylons, even if it’s “dense” sand. Nor is it clear that the borings were taken where the pylons will be installed.
You'd think that for all the millions of dollars and the many years that Caltrans has had to prepare for the Willits Bypass that they'd at least have had an independent geologist review this stuff to see if an elevated viaduct is viable.
Instead, we get official announcements about how great the bypass will be for fish!
And this is a downsized Bypass, a partial Bypass.
The project’s critics are right that highway traffic is down compared to when the project was first proposed. And they’re right that more money should have been spent on local traffic and safety improvements before millions were set aside for a Bypass that looks more and more like a garden variety boondoggle every day.
It's really not even much of a Bypass.
1. there's no Highway 20 interchange — it was removed from the design to save money — meaning that traffic to the Mendocino Coast, a third of which passes through Willits and could have been bypassed with an interchange will still go through downtown Willits.
2. The pilings will sink into the notorious Little Lake Valley fill which will crack the elevated road surface, making it a constant source of maintenance and road closure, putting the “bypass” traffic right back on Main Street Willits, which by then will have been turned over to the City of Willits for maintenance. And Willits hasn't obtained — much less asked for — a guarantee from Caltrans to pay for such road maintenance.
Because of these geological problems, combined with the state’s historic difficulty in adequately funding large road projects, there’s a good chance that the project will run out of money mid-way, leaving the Bypass in mid-air.
Caltrans also has no drainage management plan in place, either during construction or afterwards. Road construction always changes drainage patterns, as anyone familiar with the Cloverdale bypass can tell you.
The Willits Bypass involves “seven mainline structures and four ramp structures. The major structure in this group would be the Floodway Viaduct that would span the Little Lake Valley floodway. This viaduct would be designed to convey the base flood without substantially increasing the 100-year water surface elevation.”
In other words, a big segment of the Bypass will be an elevated roadway that will look something like this cartoonish Caltrans-provided sketch under which considerable flooding and water flow will be channeled, further eroding the stability of the sand under the pylons:
According to Caltrans, “To minimize or prevent settlement, Caltrans will incorporate foundation treatments or long-term settlement periods into the design and construction of the project.”
But nowhere in any Caltrans planning document does Caltrans say what those “foundation treatments” will be. Nor is the statement that Caltrans will incorporate “long-term settlement periods into the design and construction of the project” explained. It seems to mean that Caltrans will put the pylons in and let them sit there for some period of time while building the actual elevated roadway. How one might incorporate “long-term settlement periods” (of up to ten years) into the design of the project remains a mystery.
Even though the “geological challenges” that the Willits Bypass presents will be considerable, the Caltrans planning documents merely say that “foundation treatments” and “long-term settlement periods” will somehow “minimize or prevent settlement.”
By their own geological reports there will be no “prevention” of settlement for the viaduct and the primary way to “minimize settlement” seems to be to wait for up to ten years.
Prediction: Bypass construction will begin next year. Not long after that (probably the first wet winter), Caltrans will discover that things are sinking and cracking and slipping and sliding. The project will have to be put on hold while Caltrans reconsiders what to do. Costs will increase dramatically. Large cost overruns will be projected. The State being chronically broke, there won't be enough money to finish the project. Highway 101 through-traffic will continue on its congested way through downtown Willits, which will be left with a partially built, crumbling monument to bad planning: a freeway to nowhere — and no bypass. Stuck in the mud.
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