Mendocino County, California Bridges: Highway 1 Bridge across Ten Mile River

September 2017 (39.54917, -123.76278) Ten Mile River Bridge

Ten Mile River Bridge (10 0274) is an eight span prestressed concrete box girder bridge that was built in 2009. It replaced a timber deck truss bridge that had been built at this site in 1954 (see photo below, courtesy of the Mendocino County Historical Society).

With the tight radius curve at the south end of the bridge along with it's streamlined appearance and the dramatic landscape of water, sky, and rugged hills, this bridge provides some visual excitement. Note the open barrier rail and sidewalk, which is appropriate for a bridge along the coast.

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Mendocino County, California Bridges: Highway and Railway Bridges across Pudding Creek

September 2017 (39.4586, -123.8078) Pudding Creek Bridges

A highway bridge and a railway bridge (now converted to a pedestrian bridge) cross Pudding Creek a few hundred yards from each other. The Highway 1 Bridge (10 0158) is an eight span, precast concrete channel beam bridge that was built in 1959. The bridge was seismically retrofit in 1996. Large diameter piles were placed at the ends of enlarged bent caps. This is called a 'superbent' and is a commonly used seismic retrofit to more firmly anchor a bridge into the ground. The simply supported channel beams (upside down bathtub sections) were securely anchored to each other and to the bents. It looks like at some point a water line was attached to the west side of the superstructure.

At the end of the 19th century Union Lumber built a 10 mile long railway to bring redwood logs (that were being deposited into Ten Mile River) to their mill at Fort Bragg. More information on the bridge, the railroad, and the lumber company is available on the Mendocino Model Rail Website.

Pudding Creek Trestle is a 515 ft long wooden bridge that was built by the Union Lumber Company in 1915. The railroad bridge became a truck bridge when the railway was converted to a haul road in 1949. The logging operation ended in the 1970s and the truck bridge became a pedestrian bridge in 2007.

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Mendocino County, California Bridges: Highway 1 Bridge across the Noyo River

September 2017 (39.42694, -123.80667) Noyo River Bridge

Continuing north on Highway 1 we arrived at the Noyo River Bridge (10 0298). This is a three span continuous, prestressed concrete box girder bridge. It has a 325 ft long main span and it was built in 2005. It's an odd looking bridge with columns that are recessed below the soffit to imitate a bridge on bearings. The columns have a stout shape with extra concrete that (hopefully) will spall off to allow the ductile core to undergo large displacements without breaking during an earthquake.

There was a fight between Caltrans and the community about various aspects of the proposed design of the bridge.  The bridge was to be located extremely close to commercial buildings along the bank and it doesn't look like a typical coastal bridge. One resident, Vince Taylor, fought Caltrans on the solid barrier rail that was originally proposed for the bridge. He provides a history of his hard-fought victory on the internet.

Tony Phillips provides an excellent pictorial history of the six different bridges that crossed the Noyo River near its mouth during the last 150 years. The first structure was a drawbridge that was built in 1861. Subsequent bridges were truss bridges until the current haunched box girder bridge was built.

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