Montopolis Bridge
a.k.a. US 183 Bridge at the Colorado R.;TV0265-01-034
US 183, 8.1 mi. S of jct. with I-35, Austin, TXThe Montopolis Bridge was built from 1937 to 1938. This custom-designed Parker through truss bridge with five spans and special decorative features is significant under Criterion C for embodying the defining characteristics of a THD truss bridge. As such, it meets National Register Criterion C in the area of Engineering at a state level of significance.
Although it now serves traffic on US 183 (former State Highway 29), the Montopolis Bridge was built to carry State Highway (SH 71) over the Colorado River east of Austin at Montopolis. The village of Montopolis, since absorbed into Austin, was a small settlement southeast of Austin. SH 71 originated in downtown Austin along East 1st Street, now Cesar Chavez Street, paralleling the river for about a mile beyond the city limit before turning south to cross the Colorado River. The route continued southeast towards the Gulf Coast through Bastrop, La Grange, Columbus and El Campo.
NPS Form 10-900-a OMB Approval No. 1024-0018 (S-66) United States Department of the Interior National Park Service National Register of Historic Places Continuation Sheet Historic Bridges of Texas Montopolis Bridge Section number 8 Page 5 Travis County, Texas Statement of Significance: The Montopolis Bridge was built from 1937 to 1938. This custom-designed Parker through truss bridge with five spans and special decorative feamres is significant under Criterion C for embodying the defining characteristics of a THD truss bridge. As such, it meets National Register Criterion C in the area of Engineering at a state level of significance. Although it now serves traffic on US 183 (former State Highway 29), the Montopolis Bridge was built to carry State Highway (SH 71) over the Colorado River east of Austin at Montopolis. The village of Montopolis, since absorbed into Austin, was a small settlement southeast of Austin. SH 71 originated in downtown Austin along East 1st Street, now Cesar Chavez Street, paralleling the river for about a mile beyond the city limit before mming south to cross the Colorado River. The route continued southeast towards the Gulf Coast through Bastrop, La Grange, Columbus and El Campo (see Figure 2). In the early 1940s, the Montopolis Bridge also began serving traffic on SH 29 (now US 183). SH 29, also known as the Middle Buster Highway, originally ran north-to-south through downtown Austin on Guadalupe Street and Congress Avenue, crossing the river at the Congress Avenue Bridge. The route continued south through Lockhart, Luling and Victoria to Port O'Connor on the Gulf Coast. In order to relieve traffic across the Congress Avenue Bridge, the route's river crossing was relocated to the Montopolis Bridge via East 1st Street. A few years later, in 1946, the rest of the route through Austin was relocated east of town to what is now Airport Boulevard, circumventing downtown altogether; the route continued to use the Montopolis Bridge crossing. By 1952, SH 29 had been improved and designated US 183.
The segment of highway in the vicinity of the Montopolis Bridge retained the shared designation SH 71/US 183 until 1974. SH 71 was relocated south of the Colorado River by 1961, but a business loop continued through town on East 7th Street and crossed the river at Montopolis. From about 1942 to 1974. the Montopolis Bridge served on two major routes through Austin. Although the bridge is now part of US 183, it continues to link the downtown area with SH 71 south of the river. This crossing is used by all traffic originating north of the river and heading east towards Bastrop.
THD built the Montopolis Bridge to replace the bridge washed out by a devastating flood in June 1935. As reported in the March 1938 Texas Parade, "It was the last of five bridges washed away by the high waters that caused severe damage to Texas roads and bridges." Regarding the replacement bridge, the article stated:
The original bridge, built by Travis County in the late 1880s, consisted of six truss spans of lengths varying between 110 and 280 feet. Texas Highway Department (THD) officials immediately went about planning for a replacement bridge and requested federal emergency relief funds. They also undertook a maintenance project to provide a temporary low water bridge. Although THD considered using a pontoon bridge, the extra cost of having round-the-clock guards to monitor the bridge made this option less desirable. The estimated cost for the temporary structure was $15,000, of which Travis County paid half.
THD implemented three projects related to the construction of a replacement bridge. The bridge itself was covered by an emergency relief project funded under Section 3 of the Hayden-Cartwright Act of 1934. In addition to extending federal relief funding established under the National Industrial Recovery Act, the Hayden-Cartwright Act provided emergency funds for the repair or reconstruction of highways and bridges on the federal aid system "which have been damaged or destroyed by floods, hurricanes, earthquakes or landslides. ..." A federal aid project encompassed the construction of a relocated segment of SH 71 extending from the eastern city limits to just past the bridge. THD engineers prepared the plans for these two projects, and because federal funding was involved. Bureau of Public Roads (BPR) engineers reviewed and approved them.
The third project was a state project covering the construction of a link between SH 71 and East 5th street. In a memo dated October 14, 1936, THD engineers informed Gibb Gilchrist, then State Highway Engineer: "The Division Engineer has recommended the construction of a short connection to be undertaken in conjunction with the adjacent 1937 Regular Federal Aid Project on Highway 71 near Montopolis, since considerable farm traffic will utilize 5th Street to reach the Community Market on 6th Street and thus relieve the congestion of traffic on East 1st Street."
Rather than use a standard design, THD bridge engineers developed a special design for the 200-foot riveted Parker through truss spans of the replacement bridge. Nine other Parker truss bridges specially designed by THD survive today. One of these, in Bell County, uses a similar design for its single truss span (refer to nomination of State Highway 53 Bridge at the Leon River, BL0015-05-060, NRHP 1995). The Montopolis Bridge is one of only two bridges with five truss spans surviving on a Texas state highway. The bridge's six concrete piers, supporting the truss spans, were designed to rest on the uniform shale strata 15 feet below grade.
As part of an effort to improve the aesthetics of bridge design, particularly for structures in or near urban areas, THD bridge engineers incorporated several decorative elements into the design of the Montopolis Bridge. The bridge substructure exhibits arched concrete bents and concrete piers with beveled copings. In addition, decorative steel railing flanks a 5-foot wide pedestrian walkway. The posts are made up of H-beams placed vertically, then cut, bent and welded to form the curved top end of the post. The top handrail consists of 3-inch piping. Below, two rows of channels are placed between the posts, facing down. Small square steel pickets of varying lengths hang from the pipe handrail to fill out the railing. These pickets run through holes in the three rows of steel channels and are welded in place. The result is an elaborate and labor-intensive decorative steel railing. This is the most decorative type of steel railing used on THD bridges. The Montopolis Bridge is one of only three surviving THD truss bridges exhibiting a pedestrian walkway with this type of decorative steel picket railing.
Although the Montopolis Bridge projects were funded from three different sources, the projects were advertised as a group and incorporated into in a single construction contract. They were advertised in Austin, Houston and Dallas newspapers. The Texas Highway Commission held bidding for the three Montopolis Bridge projects in December 1936. After reviewing the 10 bids received, the commission awarded the projects to the low bidder, the Vincennes Steel Corporation of Vincennes, Indiana. Although all 10 bids came in below the THD's preliminary estimate of $315,000, Vincennes Steel Corporation's bid of just under $254,000 came to nearly ten percent below that figure.
Work on the bridge began on February 15, 1937. By summer, the project was under investigation for labor violations. The affair began when William Lee, who was employed as a night watchman on the bridge project, complained that he had been promised a salary of $2.40 per day but only paid $12 per week. In his July 8 letter to the BPR's District Engineer in Fort Worth, he further stated that the Vincennes Steel Corporation subcontracted the foundation work to the Clarence Jones Construction Company and that the payrolls the subcontractor submitted to the Vincennes Steel Corporation had been falsified.
THD officials dismissed the complaint regarding wages since Lee was paid the minimum rate THD required. However, the allegations about the unauthorized subcontractor and the inaccurate payrolls were a cause for concern. As a result of these allegations, Gibb Gilchrist ordered the THD Division Engineer in Austin to make a complete investigation and report. In his memo dated July 17, 1937, Gilchrist underscored the seriousness of the situation: "It is particularly important that this matter be handled at the earliest possible date since it has come to the attention of the District Office of the Bureau of Public Roads. It not only involves the eligibility of this contractor [Vincennes Steel Corporation] but also the eligibility of Federal funds for payment of future estimates."
In a document dated July 30, 1937, Herbert Eldridge, Acting Bridge Engineer, stated:
He went on to state that an affidavit would be furnished declaring that the Clarence Jones Construction Company was not a subcontractor on the project.
A later memorandum regarding the investigation, dated September 2, 1937, states:
The bridge was completed on February 11, 1938, at a cost of nearly $232,000; the federal contribution through the emergency relief program for the construction of the bridge came to just over $113,000. The THD resident engineer in Austin supervised the construction which was periodically inspected by engineers from THD and BPR. The dedication ceremony was held the day after completion. The March 1938 issue of Texas Parade provided the following description of the event:
Regarding the old bridge, the article stated:
In 1962 and 1963, THD responded to increasing traffic volumes on US 183 by constructing a new bridge made up of steel girders and prestressed concrete beams adjacent to the Montopolis Bridge to serve northbound traffic. In 1995, new structures were completed to serve southbound lanes. The truss bridge was retained in place on what became the southbound frontage road, providing access to the Montopolis Road exit. This configuration lightened the traffic burden on the truss bridge, allowing for its preservation in place. Although the construction of the new structures has altered the setting of the truss bridge, as transportation facilities they are compatible with the use of the original bridge and therefore do not significantly compromise its integrity.
Although it now serves traffic on US 183 (former State Highway 29), the Montopolis Bridge was built to carry State Highway (SH 71) over the Colorado River east of Austin at Montopolis. The village of Montopolis, since absorbed into Austin, was a small settlement southeast of Austin. SH 71 originated in downtown Austin along East 1st Street, now Cesar Chavez Street, paralleling the river for about a mile beyond the city limit before turning south to cross the Colorado River. The route continued southeast towards the Gulf Coast through Bastrop, La Grange, Columbus and El Campo.
NPS Form 10-900-a OMB Approval No. 1024-0018 (S-66) United States Department of the Interior National Park Service National Register of Historic Places Continuation Sheet Historic Bridges of Texas Montopolis Bridge Section number 8 Page 5 Travis County, Texas Statement of Significance: The Montopolis Bridge was built from 1937 to 1938. This custom-designed Parker through truss bridge with five spans and special decorative feamres is significant under Criterion C for embodying the defining characteristics of a THD truss bridge. As such, it meets National Register Criterion C in the area of Engineering at a state level of significance. Although it now serves traffic on US 183 (former State Highway 29), the Montopolis Bridge was built to carry State Highway (SH 71) over the Colorado River east of Austin at Montopolis. The village of Montopolis, since absorbed into Austin, was a small settlement southeast of Austin. SH 71 originated in downtown Austin along East 1st Street, now Cesar Chavez Street, paralleling the river for about a mile beyond the city limit before mming south to cross the Colorado River. The route continued southeast towards the Gulf Coast through Bastrop, La Grange, Columbus and El Campo (see Figure 2). In the early 1940s, the Montopolis Bridge also began serving traffic on SH 29 (now US 183). SH 29, also known as the Middle Buster Highway, originally ran north-to-south through downtown Austin on Guadalupe Street and Congress Avenue, crossing the river at the Congress Avenue Bridge. The route continued south through Lockhart, Luling and Victoria to Port O'Connor on the Gulf Coast. In order to relieve traffic across the Congress Avenue Bridge, the route's river crossing was relocated to the Montopolis Bridge via East 1st Street. A few years later, in 1946, the rest of the route through Austin was relocated east of town to what is now Airport Boulevard, circumventing downtown altogether; the route continued to use the Montopolis Bridge crossing. By 1952, SH 29 had been improved and designated US 183.
The segment of highway in the vicinity of the Montopolis Bridge retained the shared designation SH 71/US 183 until 1974. SH 71 was relocated south of the Colorado River by 1961, but a business loop continued through town on East 7th Street and crossed the river at Montopolis. From about 1942 to 1974. the Montopolis Bridge served on two major routes through Austin. Although the bridge is now part of US 183, it continues to link the downtown area with SH 71 south of the river. This crossing is used by all traffic originating north of the river and heading east towards Bastrop.
THD built the Montopolis Bridge to replace the bridge washed out by a devastating flood in June 1935. As reported in the March 1938 Texas Parade, "It was the last of five bridges washed away by the high waters that caused severe damage to Texas roads and bridges." Regarding the replacement bridge, the article stated:
Julian Montgomery, State Highway Engineer, pointed out that Montopolis bridge is the last high water bridge that will be constructed by the state below the Marshall Ford Dam. The Marshall Ford is the third of a series of dams being constructed in the Colorado watershed above Austin which will adequately control the surging flood waters that battered the old bridge out and sent it whirling downstream.
The original bridge, built by Travis County in the late 1880s, consisted of six truss spans of lengths varying between 110 and 280 feet. Texas Highway Department (THD) officials immediately went about planning for a replacement bridge and requested federal emergency relief funds. They also undertook a maintenance project to provide a temporary low water bridge. Although THD considered using a pontoon bridge, the extra cost of having round-the-clock guards to monitor the bridge made this option less desirable. The estimated cost for the temporary structure was $15,000, of which Travis County paid half.
THD implemented three projects related to the construction of a replacement bridge. The bridge itself was covered by an emergency relief project funded under Section 3 of the Hayden-Cartwright Act of 1934. In addition to extending federal relief funding established under the National Industrial Recovery Act, the Hayden-Cartwright Act provided emergency funds for the repair or reconstruction of highways and bridges on the federal aid system "which have been damaged or destroyed by floods, hurricanes, earthquakes or landslides. ..." A federal aid project encompassed the construction of a relocated segment of SH 71 extending from the eastern city limits to just past the bridge. THD engineers prepared the plans for these two projects, and because federal funding was involved. Bureau of Public Roads (BPR) engineers reviewed and approved them.
The third project was a state project covering the construction of a link between SH 71 and East 5th street. In a memo dated October 14, 1936, THD engineers informed Gibb Gilchrist, then State Highway Engineer: "The Division Engineer has recommended the construction of a short connection to be undertaken in conjunction with the adjacent 1937 Regular Federal Aid Project on Highway 71 near Montopolis, since considerable farm traffic will utilize 5th Street to reach the Community Market on 6th Street and thus relieve the congestion of traffic on East 1st Street."
Rather than use a standard design, THD bridge engineers developed a special design for the 200-foot riveted Parker through truss spans of the replacement bridge. Nine other Parker truss bridges specially designed by THD survive today. One of these, in Bell County, uses a similar design for its single truss span (refer to nomination of State Highway 53 Bridge at the Leon River, BL0015-05-060, NRHP 1995). The Montopolis Bridge is one of only two bridges with five truss spans surviving on a Texas state highway. The bridge's six concrete piers, supporting the truss spans, were designed to rest on the uniform shale strata 15 feet below grade.
As part of an effort to improve the aesthetics of bridge design, particularly for structures in or near urban areas, THD bridge engineers incorporated several decorative elements into the design of the Montopolis Bridge. The bridge substructure exhibits arched concrete bents and concrete piers with beveled copings. In addition, decorative steel railing flanks a 5-foot wide pedestrian walkway. The posts are made up of H-beams placed vertically, then cut, bent and welded to form the curved top end of the post. The top handrail consists of 3-inch piping. Below, two rows of channels are placed between the posts, facing down. Small square steel pickets of varying lengths hang from the pipe handrail to fill out the railing. These pickets run through holes in the three rows of steel channels and are welded in place. The result is an elaborate and labor-intensive decorative steel railing. This is the most decorative type of steel railing used on THD bridges. The Montopolis Bridge is one of only three surviving THD truss bridges exhibiting a pedestrian walkway with this type of decorative steel picket railing.
Although the Montopolis Bridge projects were funded from three different sources, the projects were advertised as a group and incorporated into in a single construction contract. They were advertised in Austin, Houston and Dallas newspapers. The Texas Highway Commission held bidding for the three Montopolis Bridge projects in December 1936. After reviewing the 10 bids received, the commission awarded the projects to the low bidder, the Vincennes Steel Corporation of Vincennes, Indiana. Although all 10 bids came in below the THD's preliminary estimate of $315,000, Vincennes Steel Corporation's bid of just under $254,000 came to nearly ten percent below that figure.
Work on the bridge began on February 15, 1937. By summer, the project was under investigation for labor violations. The affair began when William Lee, who was employed as a night watchman on the bridge project, complained that he had been promised a salary of $2.40 per day but only paid $12 per week. In his July 8 letter to the BPR's District Engineer in Fort Worth, he further stated that the Vincennes Steel Corporation subcontracted the foundation work to the Clarence Jones Construction Company and that the payrolls the subcontractor submitted to the Vincennes Steel Corporation had been falsified.
THD officials dismissed the complaint regarding wages since Lee was paid the minimum rate THD required. However, the allegations about the unauthorized subcontractor and the inaccurate payrolls were a cause for concern. As a result of these allegations, Gibb Gilchrist ordered the THD Division Engineer in Austin to make a complete investigation and report. In his memo dated July 17, 1937, Gilchrist underscored the seriousness of the situation: "It is particularly important that this matter be handled at the earliest possible date since it has come to the attention of the District Office of the Bureau of Public Roads. It not only involves the eligibility of this contractor [Vincennes Steel Corporation] but also the eligibility of Federal funds for payment of future estimates."
In a document dated July 30, 1937, Herbert Eldridge, Acting Bridge Engineer, stated:
there remains insufficient evidence to prove the existence of a subcontract for the foundation work. It is my understanding that there is on file a Lease Agreement by the Vincennes [Steel Corporation], General Contractors, with Clarence Jones Construction Company for the leasing of equipment necessary for a sum of $1.00 and other valuable considerations. There have been three men killed on this project and it is my understanding that no insurance settlements have been made. It is understood that the Insurance Companies claim their policy is with Clarence Jones Construction Company and yet the premium payments have been made by the Vincennes [Steel Corporation].
He went on to state that an affidavit would be furnished declaring that the Clarence Jones Construction Company was not a subcontractor on the project.
A later memorandum regarding the investigation, dated September 2, 1937, states:
It is evident that all labor on these projects have (sic) been paid at least the minimum wage rate specified in the contract and that no sub-contract exists between Vincennes Steel Corporation and Clarence Jones Construction Company. . . . The only irregularities remaining, which can not be adjusted, are the excessive hours worked by approximately five individuals, employed during the first four months that this job was active. The State has made a rather extensive investigation of these excessive hours and we feel that the men were allowed to work without the knowledge or consent of the Vincennes Steel Corporation and that the company was not guilty of intentional violation of labor provisions.
The bridge was completed on February 11, 1938, at a cost of nearly $232,000; the federal contribution through the emergency relief program for the construction of the bridge came to just over $113,000. The THD resident engineer in Austin supervised the construction which was periodically inspected by engineers from THD and BPR. The dedication ceremony was held the day after completion. The March 1938 issue of Texas Parade provided the following description of the event:
Simple, but impressive, ceremonies marked the opening February 12 of the Montopolis Bridge over the Colorado River, a few miles east of Austin. The bridge affords a new high water connection into Austin over the heavily traveled Highway 71, and later will serve also as the Colorado River crossing for Highway 29, the Austin-Lockhart connection that now enters Austin over the Post Road. . . . Louise Davis and Juanita Fae Bailey, representing the two Travis County precincts connected by the bridge, cut orange and white ribbons to formally open the bridge.
Regarding the old bridge, the article stated:
The old Montopolis bridge was erected by Travis County. Immediately after the dedication ceremony. County Judge George Matthews burned the $14,000 in bonds that represented the final indebtedness on the old structure. The bonds had been retired by the state a few days previously.
In 1962 and 1963, THD responded to increasing traffic volumes on US 183 by constructing a new bridge made up of steel girders and prestressed concrete beams adjacent to the Montopolis Bridge to serve northbound traffic. In 1995, new structures were completed to serve southbound lanes. The truss bridge was retained in place on what became the southbound frontage road, providing access to the Montopolis Road exit. This configuration lightened the traffic burden on the truss bridge, allowing for its preservation in place. Although the construction of the new structures has altered the setting of the truss bridge, as transportation facilities they are compatible with the use of the original bridge and therefore do not significantly compromise its integrity.
Bibliography
Barkley, Mary Starr. History of Travis County and Austin 1839-1899. 2d ed. Austin: Steck Co., 1967.
Texas Highway Department. Plans of Proposed State Highway Improvement. Control-Section-Job No. 0265-01-007, located at TxDOT headquarters in Austin.
Texas Highway Department. Project Correspondence Files. Control-Section-Job No. 0265-01-007, located at TxDOT headquarters in Austin.
"On Texas Highways." Texas Parade, March 1938.
Texas Highway Department. Plans of Proposed State Highway Improvement. Control-Section-Job No. 0265-01-007, located at TxDOT headquarters in Austin.
Texas Highway Department. Project Correspondence Files. Control-Section-Job No. 0265-01-007, located at TxDOT headquarters in Austin.
"On Texas Highways." Texas Parade, March 1938.
Engineering
Listed in National Register of Historic Places in 1996.
About National Register Listings
The National Register of Historic Places is the official list of the Nation’s historic places worthy of preservation. Authorized by the National Historic Preservation Act of 1966, the National Park Service’s National Register of Historic Places is part of a national program to coordinate and support public and private efforts to identify, evaluate, and protect America’s historic and archeological resources.
The state flower of Texas is the bluebonnet. The flower blooms in the spring and is a common sight along the highways and in fields throughout the state.
About Travis County
Travis County Timeline
Travis County, Texas, is located in the central part of the state and encompasses the capital city of Austin. The county has a rich history that spans centuries, beginning with the indigenous Native American tribes who inhabited the area long before European settlement.
European exploration of the region began in the 17th century when Spanish explorers ventured into what is now Travis County. However, it was not until the early 19th century that permanent settlements were established. In 1835, the area became part of the Republic of Texas after gaining independence from Mexico, and the county was officially created in 1840.
Travis County was named after William Barret Travis, a Texas Revolution hero who commanded the Texan forces during the Battle of the Alamo in 1836. Throughout the 19th century, the county experienced significant growth and development, driven by factors such as the arrival of immigrants, the expansion of the railroad, and the establishment of institutions like the University of Texas at Austin in 1883.
During the 20th century, Travis County continued to evolve and modernize. Austin, the county seat and state capital, grew into a vibrant and culturally diverse city, known for its live music scene, technological innovations, and progressive policies. The county became a center for government, education, and business, attracting a wide range of industries and residents.
Today, Travis County is one of the most populous and economically vibrant counties in Texas. It is home to a diverse population and a wide range of cultural, educational, and recreational opportunities. The county's history, coupled with its present-day dynamism, contributes to its unique character and makes it a significant region in the Lone Star State.
European exploration of the region began in the 17th century when Spanish explorers ventured into what is now Travis County. However, it was not until the early 19th century that permanent settlements were established. In 1835, the area became part of the Republic of Texas after gaining independence from Mexico, and the county was officially created in 1840.
Travis County was named after William Barret Travis, a Texas Revolution hero who commanded the Texan forces during the Battle of the Alamo in 1836. Throughout the 19th century, the county experienced significant growth and development, driven by factors such as the arrival of immigrants, the expansion of the railroad, and the establishment of institutions like the University of Texas at Austin in 1883.
During the 20th century, Travis County continued to evolve and modernize. Austin, the county seat and state capital, grew into a vibrant and culturally diverse city, known for its live music scene, technological innovations, and progressive policies. The county became a center for government, education, and business, attracting a wide range of industries and residents.
Today, Travis County is one of the most populous and economically vibrant counties in Texas. It is home to a diverse population and a wide range of cultural, educational, and recreational opportunities. The county's history, coupled with its present-day dynamism, contributes to its unique character and makes it a significant region in the Lone Star State.
Travis County Timeline
This timeline provides a concise overview of the key events in the history of Travis County, Texas.
- Pre-19th Century: The area that would become Travis County was inhabited by various Native American tribes, including the Tonkawa and Lipan Apache.
1691: Spanish explorers, including Domingo Terán de los Ríos and Alonso de León, explored the region.
1835: Texas Revolution against Mexico begins, and the area becomes part of the Republic of Texas.
1839: Waterloo, a small village settled near the Colorado River, is selected as the site for the new capital of the Republic of Texas.
1840: Travis County is officially established and named after William Barret Travis, a hero of the Texas Revolution.
1842: The capital is officially named Austin after Stephen F. Austin, "The Father of Texas."
1871: The Houston and Texas Central Railway reaches Austin, facilitating transportation and spurring growth.
1883: The University of Texas at Austin is founded.
1891: The Texas State Capitol building, an iconic landmark, is completed.
1930s-1940s: The construction of dams, including Mansfield Dam and Tom Miller Dam, on the Colorado River provides flood control and creates Lake Travis and Lake Austin, respectively.
1970s-1990s: Austin experiences significant growth and becomes known for its live music scene, technology industry, and progressive culture.
2000s-Present: Travis County continues to grow in population and economic significance, with Austin being recognized as one of the fastest-growing cities in the United States.