Previous posts on the new Narrows Bridge:
- History of the Tacoma Narrows Bridges
- The Two Towers I: Intro
- The Two Towers II: Concrete Thinking
- The Two Towers III: Anchor Management Classes
- The Two Towers IV: Out & Down
- The Two Towers V: The Struts
- The Two Towers VI: To the Top
- The Two Towers VII: Stairway to Heaven
- The Two Towers VIII: Spinning Beginning
- The Two Towers IX: Wheels Over Water
- The New Bridge at Christmas
- The Two Towers X: Compacting the Cable
- The Two Towers XI: Cable Banding
- The Two Towers XII: The Cranes
For those who may be new to this series, I have been blogging the construction of the new Tacoma Narrows Bridge. See the above posts for more information on the Narrows Bridges, the engineering challenges, and a first-hand tour taken of the construction site.
My fascination with the bridge construction project has led me many times onto the existing Tacoma Narrows Bridge. The existing bridge was designed for another age: completed in 1950, when cars were smaller, traffic much lighter, and average speeds substantially less, there was little thought put into pedestrian traffic. There are two walkways, one on either side, each about 3 1/2 feet in width, with a metal pipe curbing less than 1 foot high separating the pedestrian walkway from adjacent traffic.
Walking on the bridge is an experience which requires some Zen concentration and detachment. The bridge itself moves vertically, especially at the mid-points between the anchor and the tower, and between the tower and mid-span. This vertical motion is several inches or more–especially when heavy trucks or traffic are present–and gives one a decidedly uneasy feeling, recalling for the historically mindful the first bridge which collapsed under admittedly more extreme–but similar–vertical motion.
I have, through repetition, grown rather accustomed to this motion, and no longer even much notice it. I have not yet fully grown used to the other intimidating feature of this pedestrian stroll, however: the experience of having large trucks, double tractor trailers, blow by you at nearly 60 miles an hour, less than 6 feet from your shoulder.The tunnel of light seems not far distant at all at some such moments. The slipstream definitely gets your attention.
The new bridge will have a broad pedestrian lane on one side only, which should make such ambulatory ventures far more pleasant.
In spite of these unpleasant aspects of a walk on the bridge, the rewards are substantial. The views are nothing less than spectacular, particularly on a clear sunny day, when Mount Rainier looms majestic to the North, and a spectacular panorama of the Sound is on display to the South.
The age of the existing Narrows Bridge becomes more evident as well when viewed in close proximity. Despite regular maintenance, the scars of constant exposure to salt air and harsh elements are readily apparent.
Once the new bridge is completed, the existing bridge will be closed for up to one year for a major renovation. Already, structural reinforcements on the tower struts, suspension cables, and deck bracing have been underway to improve resilience to earthquakes.
The construction on the new bridge is no more than one hundred yards to the south, and therefore superb views of this process are unparalleled. With a telephoto lens, you get up close and personal with the engineers and iron workers on the catwalks.
The water below is a constant hive of marine activity. Tugboats, cranes, and barges abound, shuffling equipment about, and stabilizing the large transport ship holding the decking.
And, every now and then, you get a real treat.
Earlier this week, I set out for some photos of the new bridge as sunset approached. Standing near mid-span, I gazed downward to notice a slowly-motoring skiff–a not unusual sight, as recreational boating is a Puget Sound passion. Off the port bow of the boat was an unusual group of eddies–not noteworthy in and of itself, as wild currents are the norm in the Narrows. But these caught my eye: there was motion within them. A dorsal fin–then another, and another, arcing gracefully in a divinely-orchestrated ballet, tossing fine mist upwards on their ascent from now-surfaced blow-holes.
A pod of Orcas was moving through the Narrows–a rare and spectacular sighting.
Their distance–250 feet below, and heading swiftly south in the gathering dusk–made better photographs a challenge–but the moment was captured, nevertheless.
The Orcas–also known as killer whales, although they are not whales, but belong to the dolphin family–are among the most widely-distributed mammalian species on earth, found in waters from the tropics to Antarctica. They have a strong, matriarchal family unit, travelling together in pods numbering between 6 and 18 members. Since female Orcas may live up to 90 years of age, the pod may well contain 4 or 5 generations of males and females.
They are extraordinarily intelligent and resourceful hunters, feeding on a variety of marine life, including salmon, herring, seals, and sea lions. They have been known to toss seals through the air to one another in order to stun and kill them; herring are often caught using carousel feeding, wherein the orcas force the herring into a tight ball by releasing bursts of bubbles or flashing their white undersides. The orcas then slap the ball with their tail flukes, either stunning or killing up to 10-15 herring with a successful slap.
While once plentiful, Orcas have become relatively rare in Puget Sound, and were placed on the endangered species list in 2005. Their habitat has been greatly affected by urban development and pollution around the Sound, and the dirth of salmon due to heavy commercial and tribal fishing. They rarely venture into the South Sound, and so a sighting here is a truly special event.
My day was complete–like the workers on the bridge, climbing the catwalks to head home for food and rest, I had a sense of satisfaction and pleasure at a good day over the Narrows.
Next time around, we’ll take a look at another huge and fascinating stage in the bridge construction: raising the deck sections.