Chief John Ross Bridge

​The Chief John Ross Bridge, also called the Market Street Bridge, is the only highway movable bridge in Tennessee. The main span is a steel ribbed through arch that is a double leaf bascule. This is unusual because most moveable bridges use a truss or plate girder. This bridge is one of the largest bascule bridges ever built. However, each bascule leaf only opens to a 45-degree angle, whereas most bascule bridges open further, and some open to near 90 degrees. The bridge also features an impressive number of approach spans, with three closed spandrel concrete deck arches on either side of the bascule span. Beyond this, there are additional concrete deck girder approach spans.

The bridge was constructed from 1914 to 1917 and at the time of its completion, it was the longest rolling-lift bascule span in the world. The local newspapers also claimed that the concrete arch approach spans made the bridge the largest concrete bridge in the South. However, this was never officially substantiated.

The double-leaf bascule is a rolling lift bascule, and features counterweights above the arch on both leaf ends. Each leaf has a 25-horsepower motor that initiates the movement until the counterweight takes effect. When the bridge is closed, each bascule leaf closes to form a central arch. The operator's control room is at the southeast corner of the bascule span. It rests on concrete support arches and is above the pedestrian walkway.

The bridge was officially named the Chief John Ross Bridge in 1950, although it is still typically referred to as the Market Street Bridge. It was named after the longest serving (1828-1866) principal chief of the Cherokee Nation.

The bridge was built due to the increasing population and growing volume of vehicular traffic in Chattanooga. The nearby Walnut Street Bridge was built in 1891 and was designed for streetcars, horse-drawn vehicles, and pedestrians, and was no longer capable of handling the traffic demand. The new bridge was primarily designed out of concrete because of the maintenance issues on the metal Walnut Street Bridge.

Construction of the bridge began on November 16, 1914. The concrete for the footings was mixed on either side of the river, then delivered in 20-gallon buckets. The buckets were transported using cable lines that were supported by steel towers on either bank of the river. By the fall of 1915, about 70% of the concrete bridge span and pier work was completed. However, there were problems with pier 5 (piers 3 and 4 support the bascule span), and more digging was necessary to create a solid foundation. While this cost extra money and labor, ​it did not significantly delay construction. Unfortunately, a flood in December of 1915 washed away span 3, and additional floods in 1915 and 1916 caused delays in the construction. The bascule span was installed in July of 1917, and was first tested in early August of 1917. The test went well, and the bridge was opened on November 17, 1917. It was originally scheduled to open in early 1916.

The bridge was originally constructed with a double-track trolley car line in the center. These were removed around 1940 to increase vehicular traffic capacity, which included city buses. The first major rehabilitation project occurred from 1948-1949. This project included a structural assessment, re-flooring the bascule span with a steel grid deck, replacing sections of the sidewalk, and painting the steel. In April of 1950, an electrical worker unintentionally touched an electric trigger while greasing the lift release mechanism. This caused the bridge to lift suddenly, which damaged the gears and left cars trapped on the bridge until the counterweights could be lowered.

The Chickamauga Dam was constructed in the 1930’s, and the bascule was used minimally after this. The nearby P.R. Olgiati Bridge (also called the Williams Memorial Bridge) was built in 1959 and reduced the traffic on the Chief John Ross Bridge. In early 1970, it was discovered that the bascule was not operating properly when vessels could not pass under the bridge during a flood. The lift control system was subsequently rehabilitated in 1974, and again in 1977 after vandalism to the control room caused an emergency closure of the bridge.

The adjacent Walnut Street Bridge closed suddenly in 1978 due to its condition and narrow lanes. This increased the traffic on the Chief John Ross Bridge, especially during the morning and evening rush hour. Later that year, plans were developed for a major project to rehabilitate and beautify the bridge. However, this construction never actually took place, and the only work that was ever done was an inspection of the lift mechanism in 1979 and resurfacing of the deck in 1980.

The Veterans Memorial Bridge was built about a quarter mile east of the Chief John Ross Bridge in 1984. This alleviated the traffic on the bridge, but discussion about replacing the bridge still began in the summer of 1985. While the bridge was structurally sound, the bascule span was costly to maintain. More importantly, the bridge did not meet the navigational standards for height and span width, but it was also determined that the supports did not obstruct or restrict river navigation. There was also fear that the Chief John Ross Bridge would fall into disrepair like the adjacent Walnut Street Bridge. However, the suggestion to replace the bridge was not popular with the local residents, especially by the Moccasin Bend Task Force, who was responsible for planning the downtown riverfront development. Eventually, the idea for a replacement bridge was abandoned.

The bridge was rehabilitated again in 1986. This project included painting, repair and replacement of the wooden sidewalk, repair of the counterweights, the addition of navigational lights and repair of the concrete arch supports. Plans for another rehabilitation project began in 2001, with construction anticipated to begin in March of 2003. However, an inspection in August of 2003 found cracks and deterioration in the retaining walls, piers, concrete beams, and bridge deck. The project scope was expanded, and it was delayed until 2005 to allow for the business owners and residents of North Chattanooga to plan for the closure.

The project began on September 18, 2005, with a full closure of the bridge. The project included adding concrete to the handrails, arch fascia details, obelisks, piers, and substructure, adding light fixture to the obelisks, restoring the operator’s house, adjusting the traffic lanes, and expanding the sidewalks from six-feet to nine-feet. The bridge reopened on August 4, 2007, which was about a month ahead of schedule.

The bridge is closed four times a year to allow for a brief inspection and to test the hinge mechanism.