a 13.5-mile tunnel will make or break california\'s bullet train

by:Gewinn     2019-08-21
One day, when the first California bullet train leaves San Jose, a key part of the journey will be 13. 5-
The winding peaks of the Pacheco Pass and a mile tunnel under the valley.
The train will run at the highest speed along the straight and horizontal lines below the dark mountains, through the country\'s longest, state-of-the-art traffic tunnel.
But the vast scope and complexity of the tunnel is at the heart of new concerns about the feasibility of the national project.
An era analysis found that tunnel construction could run out of $5. 5-
The entire 54-billion budget
A mile from Gilroy to Chowchilla.
Some of the world\'s top tunnel experts believe the cost of the tunnel is around $5.
$6 billion to $14.
4 billion, reflecting the high cost of drilling through tricky geological and earthquake-active areas. The Gilroy-to-
One more route is needed for Chowchilla. 5-
A mile tunnel east of Gilroy is itself a major infrastructure project.
\"This is not good news for California taxpayers,\" said William Ibbs, a civil engineer at the University of California, Berkeley, who consulted on similar rail projects around the world.
\"Tunnels are expensive.
California high school engineer
The high-speed rail authorities are cautious but not worried.
\"We didn\'t see any problems,\" said chief engineer Scott Jarvis . \".
Randy Anderson, a tunnel expert at the agency, said the authority said it was too early to have its own cost estimate because it did not do enough geological surveys and engineering analysis.
He added that the previous plumbing tunnel works showed they were at the ballpark.
But if construction costs increase and run out of the project\'s budget, it could jeopardize plans to build the initial operating section from San Jose to the Central Valley.
State officials acknowledge that private investors will not invest money to help build other routes to Los Angeles unless they prove that the launch system is financially successful.
The existing funds of the railway authority can only be stretched at best.
It has a $21 billion startup system.
The funds include $6.
8 billion of 2008 key $ month.
Federal grants of $2 billion.
As of 2024, the cost of greenhouse gases in California was 3 billion, $5.
2 billion of the bonds issued for greenhouse gas costs after 2024.
The bond issuance plan supported by greenhouse gas costs in the future is a weak link.
Michael Tom, an expert in public finance at the University of Southern California, said the funds were not \"reliable sources of income . . . . . . .
I can\'t imagine the reason why a rational investor would take this risk.
\"The rail authority originally planned to start construction from Los Angeles, but abandoned the plan in 2016 because of the high cost --
Ironically, thanks to the tunnels under the San Gabriel and the teachapi mountains.
According to the current plan, the state hopes to start 240-
Start the system a mile in San Jose and end in an almond orchard south of Wasco.
The state estimates that the system will start operating in 2025, transporting about 3 million passengers a year.
According to the optimistic schedule of the railway administration, the entire Los Angelesto-
The San Francisco system through Pam Dale, Becker sfield, and Fresno will be up and running on 2029, requiring 1. 3-
The mile tunnel in the heart of San Francisco and the 36-mile tunnel under the Southern California mountains.
Need to establish a starter system 13. 5-
A mile tunnel was discovered earlier this year.
Officials did not consider building five shorter tunnels until the end of last year.
But according to federal records obtained under the Freedom of Information Act, the plan is too close to the St. Louis reservoir.
According to estimates from outside experts, the cost of the tunnel may significantly drain the funds available to build the start-up system.
Bent Flyvbjerg, a professor at Oxford University, studied Gao
It is estimated that the cost of high-speed rail projects around the world may be around $5. 6 billion (
The possibility of cost overruns is 50%)to $14. 6 billion (
The possibility of cost overruns is 20%).
He estimates based on data from more than 500 international tunnel projects.
On average, a comparable tunnel costs $7.
6 billion, he is an executive of one of the country\'s leading engineering companies, and he is not authorized to make public comments on the national railway plan, but has some knowledge of the project, based on the recent experience of building long tunnels in difficult geological areas, the estimated cost will increase from $10 billion to $12 billion.
Herbert Einstein, a civil engineer and tunnel construction expert at MIT, will cost about $6 billion.
Based on his experience in other projects, it is said to be low.
He said that the cost will be directly related to the construction progress, \"the cost will also increase over time. ”Nobody —
Including state officials
An ambitious dispute over the proposed timetable.
According to the current schedule, according to some experts, if there is no major issue, the system will miss the 2025 deadline to start carrying passengers more than a year ago.
The final environmental plan for setting the exact route should be passed next year and only then will the state be able to start bidding and awarding construction contracts.
The contract process will take at least a year.
Once the contract is signed, the builder will have to order the custom-
The tunnel rig was manufactured and it will take about a year to build and install it on site.
It will take at least three years for the authorities to build the tunnel, probably more, and then three years to install the tunnel high.
Voltage electrical systems, ventilation, signals and tracks, according to external experts.
Jarvis, chief engineer at the authority, said the state\'s schedule is radical and may need to be revised.
\"We are reviewing the schedule,\" he said . \".
The deadline will depend on the geological condition of the route.
When the Pacific Plate dives below the North American plate, the rocks within the scope of the Diablo are left behind.
It\'s like a knife cutting a slice from a piece of cheese, leaving a bunch of inconsistent rocks on the California coast. The tunnel —
In some places, it\'s going to be 1,000 feet underground-
It will have to pass through the hard sandstone that is scattered with weak shale, a geological structure known as the Francesco complex.
In this hybrid rock, in addition to what geologists call the \"gate ring\", there are also hard boulders of deteriorated basalt and silica.
Washington University geologists Darrell Cowen, who wrote his doctoral thesis on the Diablo series, said: \"You can go through this tunnel and you can hit a door ring as big as a car or a house.
It\'s like a fruit cake . . . . . . A rock type that does not provide the tunnel stability you want.
\"When this route passes near the huge St. Louis reservoir, the tunnel will pass through the Ortigalata fault, which is estimated to have a potential of Grade 7. 1 earthquake.
Tunnels through faults require detailed and expensive engineering.
Anderson said he was familiar with the Franciscan race in France.
The railway authority not only conducted exploration drilling along the route, but also reviewed the engineering records of two groundwater tunnels in the area.
\"We have looked at some productivity and they are very good,\" said Anderson, a tunnel expert at railway systems . \".
Engineers were able to dig about 70 feet metres a day, but in some places progress was slow, he said.
70 feet a day, two boring machines can complete the bullet train tunnel in just over three years.
Based on six days of Operation per week, there is no fault or deceleration.
However, external experts are skeptical about whether construction personnel can maintain their current schedule and budget.
\"It\'s easier for tunnels to increase costs significantly because you have limited flexibility,\" said Berkeley engineer Ibbs . \".
\"If you run into a gas bag, sand, or water, you have to solve the problem before moving on.
You\'re basically trapped.
The railway authority is building bridges, Viaduct, trenches trench and railroad track beds along Highway 29
A mile from madder to flesno, there is a contract for extra work south of Wasco.
The cost estimate recently disclosed by the railway administration shows that construction work on the section will reach $1. 7-Billion overrun
The Pacheco tunnel is not included in the increased costs.
This is also far behind the plan.
Nine years ago, voters were told that the entire Los Angeles-to-
The San Francisco system will be completed in 2020.
The date of some systems later slipped to 2022, then 2025.
Critics say that if the state reconsiders the old 1990 plan, many of the current problems can be solved through the lower passage Altamont Pass to the Gulf region west of Tracy.
Elizabeth Aleksi, co-founder of the Gulf regional regulatory organization, said: \"There was a time when they should consider other options . \".
But now the government must bear the financial consequences of past decisions.
The most important of these is the Pacheco tunnel and how to pay for it.
\"From now until the day of the first passenger ride, such a problem will happen dozens of times,\" said Martin Vaux, a transportation expert at the University of California, Los Angeles. appointed peer-
Review team for bullet trains.
\"Many people in my field expect costs to rise because of uncertainty --
Costs are usually increased.
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