Once you’ve learned about McCullough bridges, possibly by reading Crossings: McCullough’s Coastal Bridges, you won’t just drive through or over them, you’ll start to experience them.
If you’re driving through a McCullough bridge with arches, look for the aesthetic details, which make each bridge unique. Are there entry pylons? Or elaborately decorated stairways at both end? While driving through those arches, look at them carefully—are they reinforced concrete or steel (steel have rivets)? All arches you drive through are through arches, but are any of them tied arches? In a tied arch, the outward-directed horizontal forces that try to flatten the arch are redirected and become compression arches, squeezing the ends together and connected by the road deck or tie rods. It sounds complicated, but just picture a bow with the string stretched between. This makes one integrated ––and stronger––structure. Hence the alternate name “bowstring” arch.
If there are no above road deck arches, stop and look underneath. This is the most interesting view of many McCullough bridges, but it does require stopping the car. And all his bridges require a side view to see the total bridge. Depending on the approaching roadway, you may get the view as you approach. If not, stop the car to fully appreciate the full effect of each bridge.
I’ll cover all 12 McCullough bridges, including just enough info to change simply crossing into an exciting experience. I’ll do three at a time––in four separate blogs. Here are the three most northerly bridges:
* Wilson River Bridge––This small span in Tillamook, along with Big Creek and Tenmile bridges also built in 1931, were among McCullough’s most challenging bridges. Their 100-foot wide channels had sandy foundations, which prevented McCullough from using traditional arches that required large sturdy abutments (end supports) to counter lateral thrust (pushing out). The bridges crossed streams that were quite close to the waves with high water levels close to the road deck and high salt content in the air. The high water level ruled out reinforced concrete deck girder spans with their more numerous supports and the high salt content ruled out steel because of corrosion.
McCullough designed a 180-foot bridge with a 120-foot, reinforced-concrete fixed arch. A fixed arch can have much lighter abutments on either end and practically holds itself up. These were among the first bridges of this type in the United States and the first in the Far West. McCullough also used fixed arches on his larger bridges. (See two of them on the Siuslaw River Bridge photo above.)
Because of this innovative arch design, McCullough made the list of top bridge designers in 1999 when ENR (formerly Engineering News-Record) celebrated its 125th anniversary by publishing a list of the top people who had made outstanding contributions to the construction industry since 1874.
* Depoe Bay Bridge––This bridge in the town of Depoe Bay has a deck arch design where you have to look below the bridge to see the interesting part. Although it is called the Depoe Bay Bridge, it is actually two bridges side by side that are each 312 feet long. The original was built in 1927 and the slightly wider second bridge was built in 1941. The bridge was widened to accommodate the four-lane section of the highway on either end. When you stop to view the deck arches that sit side by side, it’s possible to walk under the road deck on a walkway to the other side. What a great opportunity to view the undersides up close to see how the wider bridge matches the original.
The Depoe Bay Bridge spans what is called the world’s smallest navigable harbor, and the bay is home to several resident gray whales each summer.
* Rocky Creek (Ben Jones) Bridge––This is another deck arch design and the only McCullough bridge that was originally on Highway 101, but is no longer on Highway 101. It didn’t move; the highway did. It was redesigned wider and slightly farther east up over Cape Foulweather. The bridge is on the old highway section about 0.1 mile off the present one. The old highway leads to Otter Rock and is accessed just south of the Rocky Creek State Scenic Viewpoint. This section of old highway is now one-way and partially one lane due to part of it sluffing off a few years ago during winter storms. It is easiest approached from the north just past Rocky Creek Viewpoint. From the south turn into the left-hand turn lane for Otter Crest Loop after climbing up and over Cape Foulweather. Once on the old highway (Otter Crest Loop), it isn’t far; if you blink twice you’ve passed it.
This bridge was built in 1927, is 360 feet long, and is an excellent example of a reinforced-concrete deck arch. But you have to turn into the interpretive area and look back to see the 160-foot deck arch below the road deck. This bridge looks almost new because of having received major restoration work and cathodic protection that will ensure decades of future use. The interpretive panels explain the importance of McCullough, cathodic protection, and Ben Jones. The Rocky Creek Bridge is also called the Ben Jones Bridge. It was named to honor Jones, a state legislator from Lincoln County, who introduced legislation in 1919 to build the Oregon Coast Highway. He is now known as the “Father of the Coast Highway.”
Much of the information here about these bridges can be found in Crossings. Next week I’ll cover Yaquina Bay, Cummins Creek, and Tenmile Creek bridges unless something exciting happens to my book this coming week. Then the three bridges will be bumped to a future blog.
I hope you enjoy experiencing the bridges as much as I do.
Crossings: McCullough’s Coastal Bridges can be yours for $24.95 plus $3.99 shipping. Order from Pacific Publishing at http://www.connectflorence.com or firstname.lastname@example.org. It is also available on the coast in bookstores, museums, and gift shops; in Eugene at the airport, the historical museum, and several bookstores; and in Portland at Powell’s and the Oregon Historical Society.
Judy’s PowerPoint presentations with book sales/signings:
February 19, Sunday, 3 p.m.––Port Orford Library, Port Orford (1421 Oregon Street [Hwy 101])
March 29, Thursday, 7 p.m.––Coos Bay Public Library, Coos Bay (525 Anderson Avenue)
Judy guest on TV show:
March 13, Tuesday, 2:30––The Author’s Forum, a talk show with host Dr. Veronica Esagui, chiropractic physician, author, and public speaker, on Portland area public access television (channel TBA)