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Tuesday, June 9, 2020


University Avenue facing East passes under the Georgia Street Bridge, 1930
GUEST BLOG / A narrative description of the Georgia Street Bridge by the United States Department of the Interior, National Park Service, National Register of Historic Places.

Yes, it is homely, but San Diegans living in and around historic North Park, Hillcrest and University Heights would have nothing to do with replacing the early 20th century structure with something more modern [and better looking].

To make sure the bridge officially ID-ed as CalTrans Bridge #57C-418 would always grace our part of town, activists led by Alexander Bevil, and many others waded through the red tape and had the span placed on the National Register of Historic Places.  That was accomplished in Feb. 1999.

Located between the San Diego communities of Uptown and Greater North Park, the Georgia Street Bridge is situated in a moderately dense commercial/residential district. Completed in 1914, the bridge [designed by architect James R. Comly and built by Edward T. Hale] and its flanking retaining walls represent a unique design solution to a difficult engineering problem.

Besides supporting the concrete roadway carrying Georgia Street
across the University Avenue Grade Separation Cut, the bridge's thick reinforced concrete ribbed arches have the Herculean task of preventing the cut's reinforced concrete walls from collapsing upon the roadway below. Rising some 50 feet above University Avenue, the open-spandrel arch bridge serves a monumental and artistic [by some] gateway between the communities east and west of the historic University Avenue Grade Separation Cut.

During the bridge's period of historic significance. 1914-1948, the east and
westbound tracks of the San Diego Electric Railway's East San Diego Line traveled under the bridge along University Avenue.

Georgia Street modernization was completed in May 2019 and now shows the open balustrades that were sealed in 1948.  Also the lamp posts returned.

With the line's discontinuance in 1949, the City merely covered over the tracks with a layer of concrete and asphalt. During this time the bridge also featured an open balustrade along the upper deck railing and those of the twin retaining walls. However, these were filled in sometime after 1947, perhaps due to safety reasons. Other alterations include the application of a gunite-like coating over the bridge and retaining walls' entire surfaces. This was done to cover up areas of splayed concrete and exposed
steel reinforcing rods (a problem that continued until a significant repair project, 2017-19). Also missing are two pairs of Arts and Crafts-style concrete lampposts that used to be mounted on either end of the upper deck's railing. "Ghost" marks in the concrete reveal their former location.

Despite these alterations, the bridge and retaining walls still retain all seven aspects of their original historic aspects of location, setting, design, materials, workmanship, feeling, and association.

Structurally, the Georgia Street Bridge comprises three interrelated structures. The first is an open-spandrel single-span reinforced concrete ribbed arch bridge. Its primary purpose is to support the asphalt-covered reinforced concrete deck carrying Georgia Street across the University Avenue Grade Separation Cut. The second and third structures are a pair of flanking twin reinforced concrete retaining walls.

These keep the cut from collapsing upon the roadway between Park Boulevard and Florida Street. The bridge's 69-foot long by 30-foot wide deck permits two lanes of automobile traffic to cross the cut.

Cantilevered sidewalks extending some 5 feet laterally beyond the roadway allow pedestrians to use the bridge to travel between two built-up residential districts along Georgia Street. Solid reinforced concrete closed panel railings protect those walking along the sidewalks from falling into the roadway below. Historic blueprints and photographs indicate that the railings once featured an open arch balustrade, with separate balusters lined up between modified-Doric-style piers similar to those found on other contemporary monumental style bridges built throughout the nation.  

The bridge's most distinguishing design feature is a set of three parabolic reinforced concrete ribbed arches beneath the roadway deck. Hinged at either end and at mid-span, the thick concrete arches support a series of columns that are joined at the top by smaller semi-circular spandrel arches.

Modernization work early 2019 facing west

The ribs and arches support the roadway's concrete deck above. Rising at a point some 8 feet above a concrete sidewalk on either side of University Avenue, the base of the ribs travel upward in a symmetrical parabolic curve to a point some 30 feet above the roadway at mid-span. Viewed from a distance, the bridge's thick ribbed arches, open-spandrel arched arcade, as well as the roadway's closed rail deck above, combine to give it its monumental appearance.

The Georgia Street Bridge also appears to be the only thing keeping the twin reinforced concrete retaining walls flanking either side of the University Avenue Grade Separation Cut from crashing down upon the roadway below. Each wall runs approximately 680 feet between Park Boulevard and Florida Street along the respective north and south perimeters of University Avenue's 80-foot wide asphalt-covered roadway.

The truncated parabolic walls range in height from approximately 1 foot at either end to 34 feet where it reaches the Georgia Street Bridge. Adding stability and strength to the wall's surface are a series of engaged pilasters running at 10-foot intervals along the wall's surface. Except for three sections on either end, semi-circular arches connect the pilasters' crowns, forming a blind arcade. The pattern of the blind arcade's semi-circular arches mimics those of the bridge. Also, like the bridge, the retaining walls feature a closed panel railing along its upper edges. Again, like the bridge, these once featured that open balustrade.

Three small but interesting features also adorn the reinforced concrete wall's surface. The first are two pairs of metal eyebolts. Once used to anchor electric trolley wires suspended above the roadway, each eyebolt is affixed near the top of the wall approximately 8 feet west of the wall/bridge junction, and an equal distance east of the same junction.

During the bridge's period of historic significance, the trolley wires provided electricity to streetcars traveling through the University Avenue Grade Separation Cut. The streetcars were an important factor in the growth of a number of "streetcar suburbs" that developed east of the cut along University Avenue between 1914 and 1948. With the discontinuance of streetcar service throughout San Diego in 1949 city crews merely covered over the tracks with a layer of concrete and asphalt.

The second feature is a small bronze plaque beneath the southeast corner parabolic rib/wall junction at eye-level above the sidewalk. Dating from the time of the bridge's completion in 1914, the plaque commemorates the work of its designing engineer, James R. Comly and builder, Edward T. Hale. Directly below the plaque is the third and final feature: a brass U. S. Geodetic Survey Benchmark installed in 1927.

In addition to the filling in of the railings, alterations include the coating of the bridge and retaining walls with a spray coating of gunite. Despite these alterations, the bridge and retaining walls still retain their historic integrity. They still reflect their original location, setting, and association with the historic gateway to San Diego's early streetcar suburbs. The bridge's design, original construction materials, and workmanship contribute to the feeling of a particular period in San Diego's development as it sought to provide a monumental gateway to a burgeoning early 20th century suburban district.

The University Avenue cut connecting North Park (in distance) with Hillcrest and University Heights is shown in 1907.  Compare this image with the 1930 photo at top of this blog to see how much the area grew from 1907 to 1930.  Below, is a 2019 image offering the same viewpoint.

Historic Places Registration Form.   Click here.

New image of Georgia Street bridge.   Click here.


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