State Highway 27 Bridge at the Guadalupe River

The State Highway 27 Bridge at the Guadalupe River was constructed from 1937 to 1938. This custom-designed Parker truss bridge with its combination of typifying features is significant for embodying the defining characteristics of a THD truss bridge. The practice of sinking the foundation well below the grade line in anticipation of future scour makes this bridge significant for "employing technically complex, advanced or innovative designs or construction methods." As such, the bridge meets the National Register criterion in the area of Engineering at a state level of significance.

The Guadalupe River bridge was built to replace a truss bridge built by the county in 1887. As reported in the THD Eleventh Biennial Report, the 1887 bridge suffered a "light load capacity and inadequate roadway width.." The bridge was located one and a half miles due west of Cuero on a segment of highway shared by SH 27 and SH 72. A third route, SH 29, crossed the river 2 miles southwest of Cuero on what was known as the Clinton Bridge, a truss bridge built by the county in 1886. This bridge was on a dangerous curved alignment and was also in need of replacement. In order that the new bridge could serve all three routes, THD rerouted the three highways to lead to a new crossing southwest of Cuero, just half mile upstream of the Clinton Bridge.

SH 27, now US 87, was an east-to-west route that originally linked El Paso with Fort Stockton, and later extended further east to San Antonio, Cuero, Victoria and Port Lavaca. SH 72 ran a short distance through Central Texas, originating in Brenham and extending southwest through La Grange, Hallettsville, Cuero and Yoakum to Kenedy. SH 29, now US 183, ran north-to-south from Austin through Lockhart, Luling, Gonzales and Cuero, and originally continued southeast through Victoria to Port Lavaca. By the mid-1930s, this southeastern section was relocated further south through Goliad and Refugio to Aransas Pass on the Gulf Coast. The section of SH 29 immediately south of Cuero, also known as the Cuero- Goliad Road, was not maintained by the state but rather held a conditional designation as a state highway. However, a project to upgrade the section and fully incorporate it into the state highway system was planned for 1938 and executed that year.

Planning for the new bridge began with two preliminary site inspections THD conducted on July 15 and November 12, 1936, with the participation of Bureau of Public Roads engineers. Site conditions revealed the need for a relief structure on the north side of the main bridge. As reported in the November 12 report, the engineers agreed that the approach spans should consist of "pile bents with a minimum opening of not less than 40 feetbetween spans, there being considerable drift in evidence at this site." The bridge site was located at an extreme bend in the river, increasing the potential for rushing floodwaters to erode the riverbanks. Evidence of scour on the river's high north bank prompted them to recommend the use of a 250-foot through truss for the main span, "in order to place the north pier well beyond the above-mentioned high bank..." The report went on to discuss the necessity of a pedestrian crossing:

This bridge will be located approximately four miles from the town of Cuero and there exists a large number of farmhouses which, of course, cause more or less pedestrian traffic. It was mutually agreed that a sidewalk on the structure was not necessary but that refuge walks would be a considerable advantage on a bridge of this length. The State Highway Department should give consideration to the placing of refuge walks on this structure as a safety feature for pedestrian traffic.

Despite the apparent need for such an accommodation, neither sidewalks nor refuge walks were designed into the structure.
As reflected in his November 13, 1936, memorandum to J.G. Rollins, Chief Engineer of Designs and Construction, State Highway Engineer Gibb Gilchrist urged that the replacement project be made a high priority:

I want every possible concentration [of effort] on the bridge at Cuero which has been included in the 1937 [Regular Federal Aid] Program. It is rather necessary that bridge be under construction early...

Engineers from THD and BPR subsequently held a location inspection on November 23, 1936. No changes to the preliminary design were made, and an application was made to BPR for approval of the bridge project statement. On December 22, 1936, BPR approved the project statement subject to review and approval by the War Department if that agency considered the Guadalupe navigable at the bridge site. This was not the case, and planning for the bridge continued with the preparation of the plans, specifications, and estimate for submittal to BPR.

At about this time, THD received results of test borings made at the bridge site, showing a clay and sand subsoil. As described in the report titled Texas Highway Department, 1927-1937, "the foundation conditions in the vicinity of this project required special design consideration to provide a stable, yet economical, substructure. Concrete caisson type piers founded on untreated timber piling were adopted for the main span and precast concrete piling for the approach spans." Anticipating further scour of the high north bank, THD engineers designed the caisson supporting the north pier to be sunk 41 feet, with 17 feet of soil covering the top of the caisson. As a result, about half of the pier was submerged in soil. This configuration ensured that future erosion would expose only the pier and not the caisson foundation. Plans called for the use of a temporary cofferdam to excavate a 17-foot deep hole in which the caisson would be set for deeper excavation.

The extra labor and materials required for this effort raised the cost estimate to $310,700. In his January 11, 1937, memorandum, Herbert Eldridge, Acting Bridge Engineer, described the situation to D.C. Greer, who had replaced Rollins as Chief Engineer of Designs and Construction:

The plans for this project... have recently been completed. This proposed work is programmed under ... the 1937 Regular Federal Aid Program with an allotment of $200,000.00 (Total State and Federal Funds). An estimate based on the completed plans indicates an overrun of $110,700.00... The cost of these structures is substantially increased due to the unusual substructure design necessitated by the type of foundation materials encountered at this locality, and it is not considered feasible to materially reduce the cost of construction and at the same time provide the proper installation.

Gilchrist advised that a reduction in cost would result in a substandard design. He advised that, if necessary, the overrun could be financed with accruals from other projects. THD submitted the PS&E the next day, and on January 25 BPR approved them and appropriated 1937 Regular Federal Aid funds to cover the customary 50 percent of the estimated total project cost, or $155,350.
Rather than use a standard design, THD bridge engineers specially designed the bridge's riveted Parker truss span. Nine other Parker truss bridges specially designed by THD survive today. The bridge is one of just four Parker truss highway bridges with 250-foot truss spans surviving in Texas. It is one of just seven THD truss bridges with simple spans of more than 200 feet in length. The bridge`s 20 approach spans provide a lengthy approach totaling more than 1,000 feet.

The Texas Highway Commission opened bids on February 25, 1937. The project consisted of the construction of the Guadalupe River bridge and relief structure, as well as about a mile of approach roadway grading. A related project, awarded in July 1938 and completed in May 1939, covered the roughly 5 miles of roadway grading and surfacing on the relocated section of the highway. After reviewing the 10 bids submitted, the commission awarded the bridge construction contract to Cage Brothers & L.A. Turner of Bishop, Texas. The company's low bid of just over $256,000 was more than 17 percent below THD's revised estimate. The Illinois Steel Bridge Company of Jacksonville, Illinois, was subcontracted to fabricate the steel truss spans. The Texas Steel Construction Company of Fort Worth was the subcontractor for the steel erection. Construction began on April 1, 1937. The THD resident engineer in Cuero supervised the construction which engineers from THD and BPR periodically inspected. The project was completed on February 24, 1938, under budget and ahead of schedule, at a cost of just over $257,000.