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Thread: (Northern Virginia) Rail route In Tysons an uphill challenge

  1. #1
    Cyburbian Dharmster's avatar
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    Arlington, Virginia
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    (Northern Virginia) Rail route In Tysons an uphill challenge

    washingtonpost.com
    Rail Route In Tysons An Uphill Challenge
    Engineers Debate Aerial Track, Tunnel

    By Peter Whoriskey
    Washington Post Staff Writer
    Wednesday, July 27, 2005; B07

    Most people barely notice the hill that Tysons Corner is built on,
    even though, at about 515 feet above sea level, it looms as
    Fairfax County's highest natural summit. For them, the slope demands
    no more than a nudge at the accelerator.

    But for the engineers designing a Metrorail line to the area's malls
    and offices, the hill at Tysons Corner presents a significant
    obstacle: Railroad tracks generally must be laid flat or at very
    slight inclines. Otherwise, the steel wheels lose traction.

    "It's just a hill to most people, but for us, the hill in
    Tysons Corner is one of our biggest engineering challenges," said
    Dulles Project Director Sam Carnaggio.

    In fact, the fate of the entire rail project turns at least in part
    on the $100 million conundrum posed by the slope at Tysons Corner.

    The effort to extend Metrorail through Tysons, a kind of holy grail
    for Northern Virginia commuters, has reached a critical
    juncture.

    By late August, project managers must cut the estimated
    $2.4 billion cost by more than 20 percent -- or else scuttle
    the idea, they said. And as engineers review cost-cutting
    design alterations, no single greater dilemma exists than that
    presented by the hill.

    Engineers could excavate a mile-long relatively level tunnel through
    the hill. But that could be done only at a budget-busting cost
    of $132 million, cost estimators say, and project managers
    have identified the elimination of any underground passage as
    the largest single cost savings they can make.

    Running tracks on or close to the ground would disrupt traffic too
    much.

    So the alternative to the tunnel is to cross the hill on
    elevated tracks, but that creates its own problems. The aerial
    tracks and their supports could look like a concrete scar
    running through Fairfax County's "downtown," many fear. Making
    matters worse, engineering constraints could force the tracks
    to be built as high as 80 feet aboveground.

    Tysons Corner is the capital area's second-largest job center and
    home to two regional malls, and the county's comprehensive
    land development plan has long envisioned a rail line
    there -- preferably underground.

    "A tunnel rather than an elevated alignment is the preferred
    mode," according to the comprehensive plan. Aerial tracks would,
    among other things, "intrude visually."

    The dire cost-cutting challenge for the rail project arose last
    month, when engineering firms reviewing the plan, which would
    extend the Metro system from West Falls Church through Tysons
    Corner, estimated that its price had risen 60 percent,
    to $2.4 billion -- way beyond what planners and public
    officials consider feasible.

    Not only does the project lack the budget for $2.4 billion,
    planners said, but the construction effort also would flunk
    federal cost-effectiveness standards at that price.

    "We're looking at everything to find savings," said
    Josh Sawislak, deputy project director for the Virginia Department
    of Rail and Public Transportation, which is leading the
    project.

    Among the proposed cost-cutting measures are a reduction in the
    number of rail cars, a drop in the size of the train platforms and
    the elimination of some elevators and escalators at the station.

    There are drawbacks to virtually every cut, however: Reducing
    the number of rail cars would reduce the number of trains running
    at rush hour, one of the key reasons for building the project;
    shrinking the size of platforms could create safety problems;
    and eliminating escalators and elevators could run afoul of
    the Americans With Disabilities Act.

    Rejecting those other changes, however, leaves only the issue of
    the hill.

    Aside from the former county landfill near Interstate 66 and
    West Ox Road, which rises to 567 feet above sea level, the
    Tysons hill ranks as Fairfax's highest elevation, county
    geographers said.

    "It's a relatively flat county," said Charles Grymes, who
    teaches geography at George Mason University. "Unfortunately,
    railroads can't climb hills worth a hoot."

    The largest single proposed cut -- $132 million -- involves
    elimination of the mile-long tunnel that was to have traversed
    the hill at Tysons Corner and included one underground
    station.

    But completely eliminating that tunnel would raise railroad
    tracks as high as eight stories high

    The reason for the height is that railroad tracks can safely
    operate at only slight inclines. Metro guidelines generally
    limit slopes to no more than 4 percent, meaning that the tracks
    can drop no more than 4 feet over 100 horizontal feet.

    If aerial tracks were run from the top of the Tysons hill,
    the ground would slope down much faster than the train tracks
    could, leaving the tracks several stories in the air at
    times. Eventually, the track would catch up with the ground, but
    in the meantime it would create big gaps between the ground and
    the tracks.

    Engineers call this "chasing grade."

    Abandoning the tunnel configuration could cause other troubles
    as well.

    The property owners in Tysons Corner, who have agreed to put
    up as much as $400 million in tax money toward the project,
    based their offer on the original configuration of the train route.
    That offer might be rescinded if the configuration changes
    drastically.

    "To the extent that there is a significant change, the county
    runs the risk of having to go back to landowners in order to
    spend the tax money," said John McGranahan, a lawyer who
    organized the tax district.

    2005 The Washington Post Company

  2. #2
    Cyburbian Emeritus Bear Up North's avatar
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    Dharmster.....is this a standard-gauge railroad or some sort of light rail? Will it be terminating at Tyson?

    Just curious. I know so little about the rail and the transit in this area.

    Bear
    Occupy Cyburbia!

  3. #3
    Cyburbian Plus PlannerGirl's avatar
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    Va
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    Metro is part of the subway system for DC. The line will not terminate at Tysons (or so they say) but end just out past Dulles airport.

    I am of the mind they will run out of money or drive with the proposed BRAC and new security setback issues.
    "They who can give up essential liberty to obtain a little temporary safety, deserve neither liberty nor safety." Ben Franklin

    Remember this motto to live by: "Life should NOT be a journey to the grave with the intention of arriving safely in an attractive well preserved body, but rather to skid in sideways, chocolate in one hand, martini in the other, body thoroughly used up, totally worn out and screaming 'WOO- HOO what a ride!'"

  4. #4
    Cirrus's avatar
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    Aug 2003
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    Third rail, Bear Up North.

    Eventually the plan is to extend it past Dulles, but this phase of the line is planned to end on the east side of Reston, a few miles west of Tysons Corner.

    IMO if they need significant cost savings ending the line at Westpark rather than Wheile and dropping the Tysons East station should be on the table. The only truly essential, non-negotiable parts of the project are the three stations in the core area of Tysons Corner... But those three stations are absolutely non-negotiable.

    And while I think BRAC may affect the will to extend the line to Dulles (a waste of money even without BRAC, IMO), even after all this realignment Tysons Corner will still be a much larger, much more geographically condensed activity center than Fort Belvoir. So BRAC is really a non-issue for the first phase of the line.

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