Alameda County, California Bridges: Bay Farms Island Bridges (2)

June 2014 (37.74894 Degrees, -122.23628 Degrees) Bay Farm Island Bridges

Some more photos of the Bay Farm Island Bridges. The bascule spans for both bridges are on the east side of the estuary. Wooden fenders protect the pile extensions along the narrow channel.

The free end of the bascule span on the highway bridge is supported on a special bent with two rows of slightly battered piles. The free end of the bascule span on the bike bridge is supported by just another two column bent.

The bike bridge has a long, continuous pony truss superstructure on slightly battered two column bents. Work started on the bridge in 1993 and it was completed in 1995. It cost $3.5 million with funding from Alameda County, Caltrans, and the federal government. The bike bridge automatically opens when the tender opens the highway bridge. However, the bicycle bridge can be opened manually if necessary. Unlike the other bridges which use gearboxes to open, the bike bridge uses two giant hydraulic pistons to open and close. The Bay Trail carries bicyclists and hikers from the bridge onto the Island. A timber bridge carries them under the highway bridge.

Alameda County, California Bridges: Bay Farms Island Bridges (2) by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Alameda County, California Bridges: Bay Farm Island Bridges (1)

June 2014 (37.74894 Degrees, -122.23628 Degrees) Bay Farm Island Bridges

At the south end of Alameda Island are the two Bay Farm Island Bridges. Bay Farm Island (shown in the foreground of the photo) is now a peninsula due to a landfill that connected the island to Oakland and the Oakland Airport. The island used to be home to asparagus fields and oyster beds that supplied food to the restaurants of San Francisco. 

The first bridge built on this site was made of timber (in 1854) with an oyster shell deck. The current Bay Farm Island Bridge (33 0086) carries State Route 61 across the Oakland Estuary. It was built in 1953 by the California Public Works Department (now Caltrans) who continues to own, operate, and maintain it.  It's a single leaf bascule bridge, similar to the previously studied Fruitvale Avenue Bridge. Its total length is 963 ft, which is mostly steel stringers on pile extensions. It was built by Duncason-Harleson and Stolte.

There is a parallel pedestrian and bike bridge (maintained by Alameda County) that connects the bike path on Bay Farm Island to the Fernside Blvd shoreline path. It is the only bascule bridge in the US exclusively for pedestrians and bicyclists.

Alameda County, California Bridges: Bay Farm Island Bridges (1) by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Miami-Dade County, Florida Bridges: Venetian Causeway across Biscayne Bay

January 2014 (25.7898 Degrees, -80.1832 Degrees) Venetian Causeway

Continuing south, we arrived at the Venetian Causeway, a series of roads and bridges built in 1926 between islands in Biscayne Bay. According to 'Historic Highway Bridges of Florida,' it is the oldest causeway in Miami-Dade County and consists of 12 bridges across one natural and five human-made islands.

The causeway is about 2.5 miles long between Miami and Miami Beach. In 1913 a long timber trestle bridge was built from the mainland to what was to become Miami Beach. In 1925-26 the Bay Biscayne Improvement Company and the Raymond Concrete Pile Company replaced the trestle structure with the current bridges. Whenever an engineer finds out that an old bridge is supported on Raymond piles, he or she knows that an expensive repair job will be required, because these piles have almost no reinforcement. Many of these bridges underwent repairs from 1996 to 1997 but somehow they managed to retain their historic status. Much more information on this causeway is available in the above referenced book.

Most of the bridges were built very low to the water and so the bascule spans are constantly opening and closing to allow passage of boats  through the bay. All the bridges are very similar with crisscrossed concrete barriers and haunched concrete 'T' girder spans on pile extensions.

The westernmost bridge is the long, tall Venetian Causeway Bridge between Miami and Biscayne Island (shown above). It's a 2000 ft long bridge with a double bascule span and a grand entrance on the west side with obelisks marked 'Venetian Way' and 'Short Way.'

Miami-Dade County, Florida Bridges: Venetian Causeway across Biscayne Bay by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Miami-Dade County, Florida Bridges: Julia Tuttle Causeway across Biscayne Bay

January 2014 (25.81028 Degrees, -80.15028 Degrees) Julia Tuttle Causeway

The Julia Tuttle Causeway carries State Route 195 across Biscayne Bay. It includes a highway on a human-made island in the middle of the bay and bridges at the two ends. The western bridge (FDOT #870301) is 2120 ft long with steel girder spans. The eastern bridge (FDOT #870302) is 1138 ft long with precast girders on parallel two column bents (shown below). Both bridges were built in 1959 and widened in 1990/1991.

Julia Tuttle is considered to be the founder of Miami. At the end of the 19th century she owned a large portion of the land in the area and successfully promoted it for development. The Julia Tuttle Causeway became famous because for several years the island was the only place that sexual offenders released from prison in Miami-Dade County were allowed to live. 

Miami-Dade County, Florida Bridges: Julia Tuttle Causeway across Biscayne Bay by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Miami-Dade County, Florida Bridges: North Bay Causeway across Biscayne Bay

January 2014 (25.84500 Degrees, -80.14333 Degrees) North Bay Causeway

The Intracoastal Waterway widens to become Biscayne Bay between Miami and Miami Beach. Its a couple of miles wide and crossed by six causeways that we will look at over the next few days. I somehow missed the Broad Causeway to the north, but it can be studied on other websites. The North Bay Causeway is next (to the south) and includes long bridges between Miami, Pelican Island, North Bay Island, Treasure Island, and Miami Beach. The bridges at Miami and Miami Beach have bascule spans to allow boat travel through the Bay. The East Biscayne Bay Bridges (FDOT #870551 and 870085) are 17 span, 1030 ft long precast I girder bridges with a 90 ft bascule span in the center (see photo above).

The West Biscayne Bay Bridges (FDOT #870551 and 870083) are 17 span, 510 ft long concrete slab bridges with two bascule leafs in the center (see photo above).  Both the East and West Biscayne Bay Bridges sit on driven precast piles supporting bent caps. The bridges were built in 1971 with two way traffic but in 1973 parallel bridges were built (to carry eastbound traffic) and the original bridges were modified to carry just westbound traffic.

Miami-Dade County, Florida Bridges: North Bay Causeway across Biscayne Bay by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Palm Beach County, Florida Bridges: State Route 706 Bridges across the Intracoastal Waterway

January 2014 (26.93389 Degrees, -80.08333 Degrees) Indiantown Road Bridges

Continuing to the northeast, we arrived at the City of Jupiter, which is intersected by many bodies of water (see Google earth photo below).

The State Route 706 Bridges (FDOT#930453 and #930454) are two parallel bridges that include slab end spans, precast girder approach spans, and single steel bascule spans across the Intracoastal Waterway. These bridges were built in 1999, they are 1344 ft long, and they have many architectural features. The piers supporting the bascule span are very large, painted pink, and with big platforms for pedestrians to look at the waterway.

This part of Jupiter would be quite lovely except for the downtown area north of this bridge is being rebuilt. This made it difficult to get a good elevation view of the bridges. I had to walk out on a partially demolished wharf covered in vegetation to get a photo of the bascule span.

Palm Beach County, Florida Bridges: State Route 706 Bridges across the Intracoastal Waterway by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Palm Beach County, Florida Bridges: Linton Blvd. Bridge across the Intracoastal Waterway (2)

December 2012 (26.4397 Degrees, -80.0650 Degrees) Linton Blvd. Bridge

Another photo of the Linton Blvd. Bridge. I wonder why the approach spans are precast girders while the end spans are steel girders? It must somehow be more convenient for the bascule span to lock-up against steel girders. Note how the end spans are made up of many girders while each bascule leaf is made up of two very deep girders and a lot of cross-bracing.

Palm Beach County, Florida Bridges: Linton Blvd. Bridge across the Intracoastal Waterway (2) by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.

Palm Beach County, Florida Bridges: Linton Blvd. Bridge across the Intracoastal Waterway (1)

December 2012 (26.4397 Degrees, -80.0650 Degrees) Linton Blvd. Bridge

It's about four miles north from the Spanish River Bridges to the Linton Boulevard Bridge in Delray Beach. Maybe that's why the bridge carries over 20,000 vehicles a day. Still, that's a lot of traffic for a seven mile long road that's blocked by the Loxahatchee Swamp to the west and by the Atlantic Ocean to the east.

The Linton Blvd. Bridge is a 1,388 ft long structure that was built in 1981. They call it a single bridge but it's 102 ft wide with two parallel leafs that open independently. According to the Uglybridges Website, the bridge provides about 26 ft of vertical clearance over the channel in the closed position and a lot more clearance near the east side of the channel at low tide (the bascule pier is on the west side of the channel).

Like the previous bridges, the Linton Blvd. Bridge has long approaches that gradually raise the bridge over the channel. However, this bridge is supported on pile caps and it has just single bascule leafs that provide 90 ft of lateral clearance.

Palm Beach County, Florida Bridges: Linton Blvd. Bridge across the Intracoastal Waterway (1) by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.

Palm Beach County, Florida Bridges: Spanish River Blvd. Bridges across the Intracoastal Waterway (3)

December 2012 (26.38634 Degrees, -80.07104 Degrees) Spanish River Blvd. Bridges

A view from behind a trestle pier at the bascule pier, operators house, and timber fenders of the Spanish River Boulevard Bridges. Four pile extensions were cased in concrete on the left pier while only three were cased on the right pier, suggesting this was a later repair. Note the trestle spans are precast concrete girders while the end spans are steel girders. In this photo we can clearly see the counterweights that rotate downward to lift up the bascule spans.

Palm Beach County, Florida Bridges: Spanish River Blvd. Bridges across the Intracoastal Waterway (3) by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.

Palm Beach County, Florida Bridges: Spanish River Blvd. Bridges across the Intracoastal Waterway (2)

December 2012 (26.38634 Degrees, -80.07104 Degrees) Spanish River Blvd. Bridges

A closer look at the bascule spans on the Spanish River Boulevard Bridges. I spent some time trying to understand the purpose of the blue box on the right side of the photo. I finally decided it must be a counterweight for the right bascule leaf. As the counterweights rotate downward between the white concrete sides of the piers the bascule leafs are raised into the air.

Palm Beach County, Florida Bridges: Spanish River Blvd. Bridges across the Intracoastal Waterway (2) by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.

Palm Beach County, Florida Bridges: Spanish River Blvd. Bridges across the Intracoastal Waterway (1)

December 2012 (26.38634 Degrees, -80.07104 Degrees) Spanish River Blvd. Bridges

Continuing north are the two Spanish River Boulevard Bridges, which carry eastbound and westbound State Route 800 over the Intracoastal Waterway. The bridges are 486.9 ft long precast concrete trestles with movable steel bascule spans over the channel. They were built in 1971, carry 8,000 vehicles a day, and are in satisfactory condition. Today's photo shows the trestle approaches, the operator's house cantilevered from the bascule pier, and the fenders on the west side of the channel. We'll take a closer look at the bridges tomorrow.

Palm Beach County, Florida Bridges: Spanish River Blvd. Bridges across the Intracoastal Waterway (1) by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.

Movable Bridges - Brickell Avenue Bridge

The Intercoastal Waterway (a 3000 mile channel along the Atlantic and Gulf Coasts) is a good place to find movable bridges. Its safer than traveling on the open ocean and so ships travel on it and movable bridges are needed for people wanting to get to the beach. These bridges seem to open and close more often than the other movable bridges we've been studying.

The Brickell Avenue Bridge actually crosses over the Miami River just before it empties into the Intercoastal Waterway in Miami Beach, Florida. The bridge is decorated with sculptures, sconces, and a pretty tender house. It's a bascule bridge built in 1995 that replaced a 64 year old structure. It was recently widened to three lanes in each direction but it still gets backed up with traffic during rush hour. The bridge has a higher vertical clearance and the river was dredged so it doesn't have to open quite so often.

Movable Bridges - Brickell Avenue Bridge by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.

Movable Bridges - Popps Ferry Bridge

As we continued east along Mississippi's coastline into Biloxi's Back Bay we came to the Popps Ferry Bridge.

It seems like bridges along the Gulf Coast are in a constant state of disrepair. In this photo the bridge is being put back together after Hurricane Katrina came through (in August 2005). I was reviewing my trip on Google Earth and found a photo of the bridge being repaired again after being hit by a tugboat pulling eight barges in 2009. The bridge tender opened the double-leaf bascule spans for the tugboat, but the operator must have had trouble with the current because he knocked out a bridge span instead. If it's not hurricanes, or errant vessels, its oil spills for the ill-fated residents of Biloxi's Back Bay.

The Popps Ferry Bridge has long and short precast I girder approaches and a 180 ft wide channel opening. The bridge was originally built in 1979 but its been rebuilt several times.

I'm afraid we are going to see a lot more damaged movable bridges before we get out of the Gulf. We estimated there was over $2 billion in bridge damage from Hurricane Katrina and many of these bridges have movable spans.

Movable Bridges - Popps Ferry Bridge by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.

Movable Bridges - West Grand Avenue and Ohio Street Bridges

In the distance we can see the West Grand Avenue Bridge, a single leaf bascule through truss bridge with a rack and pinion lifting mechanism built in 1914. Just behind it (to the north) are the two Ohio Street Bridges that carry I-90/94 (the main east west expressway) over the North Chicago River. These bridges are double leaf bascule deck trusses built in 1954. You can walk under both bridges on the sidewalk provided along the river. The Grand Avenue Bridge provides 17 ft vertical clearance when it's closed and the Ohio Street Bridge provides 27 ft vertical clearance.

Yesterday, I relied on Historic Bridges for information on the Kinzie Street Bridge. Today I found photos and information on the Grand Avenue and Ohio Street Bridges from the Bridge Hunter. These two websites are excellent resources for information on bridges. In both cases, the information was supplemented by the book Movable Bridge Engineering.

This is my last photo of bascule bridges across the Chicago River. They provide a contrast to the heel trunnion bascule bridges we previously looked at across the Sacramento River. The visible counterweight we saw on the Sacramento River bridges (and the lift and swing spans) would have been out of place in the beautiful architectural environment of downtown Chicago, except as an occasional unique monument to the past (like the Kinzie Railroad Bridge). We can get further insight by comparing the Chicago Bridges to the movable bridges across the Willamette River in Portland Oregon (see September 2009 blog entries) and with the movable bridges across the Harlem River in New York City (see July 2009 blog entries). In each case political and commercial interests played a larger or smaller role in the resulting bridges. I think it was only in Chicago that a strong aesthetic statement from the architect and planners took precedence over purely economic interests. The result is a truly gorgeous city with many beautiful bridges. Traveling from the countryside into Chicago must have been like Dorothy and her friends entering the City of Oz.

I only have a few photos of movable bridges remaining. If I knew I was going to be writing a blog on bridges, I would have photographed many more bridges during my travels. In the next few days we'll travel to Louisiana, Mississippi, Alabama, and particularly to Florida where bascule bridges play an important role for travelers.

I just want to mention that movable bridges are generally the province of mechanical engineers who are a unique kind of bridge engineer. Whenever a highway project is planned, we create a project team and a project manager. When the project is a roadside rest area, the manager is the architect and the structural engineer (me) does what they tell me to do. When the project is a fixed bridge, I get to be manager. For movable bridges, the mechanical engineer manages the project. As long as the main technical expert manages the project things generally go well (in my opinion). Any thoughts on all of this would be appreciated.

Movable Bridges - West Grand Avenue and Ohio Street Bridges by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.

Movable Bridges - Kinzie Street Bridge (2)

An elevation view of the Kinzie Street Bridge. I read in Historic Bridges that the toe of the bascule span (not seen in the photo) was extensively rebuilt with care to use structural members of the period. However they ruined their attempt at authenticity by using high-strength bolts instead of rivets and didn't even bother to use bolts with rivet-like ends. The blog also mentioned that the original members can be easily identified (unfortunately) by all the rust on them.

Note in this photo (and in yesterday's photo) that this bridge has three through trusses with big portal frames and lots of cross-bracing so the bridge behaves rigidly as it is raised and lowered. Unlike the more streamlined bridges to the south, the tender house for this bridge is of simple timber construction. Also note the red brick structure behind the tender house where the operating machinery and counterweight are hidden.

Movable Bridges - Kinzie Street Bridge (2) by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.

Movable Bridges - Kinzie Street Bridge (1)

In the shadow of the railroad bridge sits the Kinzie Street Bridge across the North Branch of the Chicago River. The North Branch flows into the South Branch and then into the Chicago Sanitary and Ship Canal, which was built to reverse the river's flow and improve sanitation in the 1900s.

The Kinzie Street Bridge was built in 1909. Its a single leaf bascule Pratt truss bridge and provides 105 ft of channel clearance when its open. We are looking at the trunnion side with racks along its rounded end. The operating machinery has pinion gears inserted into the racks that rotate the bascule span up and down (with the help of the counterweight). We'll take another look at this interesting bridge tomorrow.

Movable Bridges - Kinzie Street Bridge (1) by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.

Movable Bridges - Kinzie Street Railroad Bridge (2)

Looking at the Kinzie Street Railroad Bridge from the side, we can see that the large concrete counterweight isn't hidden in a pit like the bridges around Wacker Drive. Apparently aesthetics isn't as big of a concern on the North Chicago River. Still, its a Chicago landmark, so the community must like this big, ugly structure.  We can see two sets of tracks on the through truss deck, and a crummy little operator's house instead of the exquisite tender houses along Wacker Drive.

The superstructure was built by the Strauss Bridge Company and so one of his patented devices pulls the superstructure into the air as the counterweight rotates onto the deck.

There's a lot of laced members on this bridge which were popular during the turn of the 19th century although today they need to be replaced with something more ductile in earthquake regions. The raised span is 170-foot long (tall?) and is supported on the east trunnion pier. According to Wikepedia, it was constructed on foundations 94 feet down into bedrock. A caisson was built to a depth of 29 feet below the river bed and then holes were drilled that eventually caused the caisson to drop the remaining 65 feet. I guess that's why the bridge is still around 100 years later, although it is now functionally obsolete.

Movable Bridges - Kinzie Street Railroad Bridge (2) by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.