The San Antonio Flood of 1921

San Antonio, located in present-day day central Texas and on the ancestral lands of the Payaya People, is a city defined by water. Through its multiple regimes of colonization, conflict, and development, San Antonio has remained at the unique intersection of waterways that come together to form the San Antonio River, which then flows Southwest to the Gulf of Mexico. And just as water is central to the city and its lengthy history, so is flooding—sometimes with devastating impact.

The summer of 1921 was typical for South Texas: each day was as hot and dry as the next. By September, the unrelenting heat had scorched ranchlands and urban lawns, and when on September 9, light rains swept across the region, the first since June, they offered a wonderful respite. Over the next twenty-four hours, however, violent thunderstorms crashed overhead, the result of a slow-moving tropical depression, and more than twenty inches of rain fell in some areas, triggering a series of frightening flash floods. Water ferociously swept through the streets, undercutting houses, commercial buildings, and bridges; killing many in their sleep.

The 1921 flood is the deadliest in the city’s history, taking the lives of more than 80 people, the vast majority of whom lived on the city’s West Side at the intersections of the Alazán, Martínez, Apache, and San Pedro Creeks. Statewide, more than 220 people died in the rampaging waters. The flood’s impact in San Antonio “went well beyond any specific tally of human loss or physical destruction. Indeed, a greater and long-term consequence was the community’s response to the critical question of how to control future floods" (Miller, 2014). 

"The total number of lives lost will never be known, but the best estimates available indicate that at least 224 people were drowned, most of whom were Mexicans who lived in poorly constructed houses, built along the low banks of the streams. Undoubtedly many others were drowned and never reported missing. Many bodies were carried miles and buried in sand, mud, and debris along the river bottoms." -C.E. Ellsworth (U.S. Geologic Survey)

Below is a mapping of those reported dead, missing, and injured shows that a vast majority of the lives most affected were on the West Side of the city. Click the points to see who they were.

In response to the flood, the Red Cross and another organization, the female-led, westside mutual aid society called Cruz Azul Mexicana, set up flood-relief stations throughout the battered West Side. These stations provided food, clothing, and employment opportunities; the Red Cross also operated a "tent city" for displaced people.

The particular vulnerability of the West Side of the city was no accident. These were the areas where the racialized and working class communities were located. The spatial vulnerabilities of the West Side are deeply tied to the social and political systems of the city, and as we will see, the ruling class of the city saw the West Side and its population as more disposable than the more affluent and white parts of the city. These spatial differences and treatments can be seen clearly through the government's economic categorization of space through redlining.

In 1935, Field Agents from the federal government sponsored Home Owners Loan Corporation visited San Antonio and interviewed bankers, mortgage lenders, and other business owners about lending practices to generate a socioeconomic outlook of the city. The organization then created "residential security maps" also known as Redlining Maps. These maps designated areas of the city as "safe" or "unsafe" for real estate investment or lending along four grades: Best, Still Desirable, Definitely Declining, and Hazardous.

This red, "Hazardous," color coding often outlined neighborhoods in the older sections of cities, where homeowners and tenants had lower incomes, or in neighborhoods that were made up of ethnic or racial minorities. In San Antonio, this was the Black neighborhood largely on the city’s east side and what the government called the "Mexican" neighborhood on the west side. This governmentally planned and sponsored denial of mortgages to these specific residents led to an increase in racial segregation, white flight, and generational poverty in many cities across the United States, including San Antonio.

The 1921 flood swept through both downtown San Antonio, where it mostly destroyed property, and the city’s west side, where it had its most fatal impact: the vast majority of those who died in the flood lived on the west side and had Spanish-language surnames; the majority were women and children. Fourteen years later, in 1935, another large flood hit the city. It did not damage the downtown, but roared through the west side barrios. So what happened in those 14 years that caused this disparity?

As a result of the catastrophic flood of 1921, the city’s Anglo leadership decided that something had to be done. In response, they planned, funded through a bond election, and built the Olmos Dam.

However, the position and creation of the dam were dominated by real estate interests and development. When the 1,941 ft dam was completed in 1927, it cleared downtown of its historic flood risk, thereby encouraging financiers to invest heavily in the area. This construction boom produced some of the tallest and most famous buildings in San Antonio, as well as made it possible for the later creation of the city's Riverwalk that draws so many tourists today. Yet the Olmos Dam provided no benefit for the west side neighborhoods. Its watersheds received some widening and clearing of vegetation after the 1921 flood, but this intervention did not prevent subsequent floods like that of 1935 or 1946 from swamping the west side. Another marker of the economic disparities and social inequities that existed in the post-flood city are manifest by clicking on the gleaming new downtown buildings that were constructed in the late 1920s, skyscrapers that were within sight of the west side "Mexican Corrals" that housed its city’s poor.

Those residential areas that Olmos Dam protected or were linked to the road that ran on top of the dam, were quickly developed as neighborhoods for middle and upper-class whites. The real estate advertisements below make explicit how in the post-flood era new housing developments were, as one of them makes clear was for "WHITE PEOPLE ONLY."

These advertisements made explicit the distance of these newly protected and developed neighborhoods from both the effects of flooding and the radicalized communities that became sacrificial zones for continued floods. The advertisement for Mitchell Place, targeted towards the white working class invokes images of separation from the "mud", a reference to the working class Black and Mexican neighborhoods that were heavily hit by the flood. That for Park Hills Estates, now part of the incorporated city of Olmos Park, may have been more subtle but the visual record testifies that it too was for whites only, and only for the city’s elite. By strategically protecting a certain population and capital interests, the Olmos Dam, paid for by the public, became a mechanism to create white enclaves, further deepening racial and class segregation and inequality across San Antonio. Just as the city’s business and real estate interests desired.

"The Olmos Dam is arguably the single most important public works project in the community's history. Yet the dam was also a failure, in the sense that the decision to build it depended on a disturbing and remarkably skewed distribution of public benefits in one of America's poorest big cities." (Professor Char Miller)

The effects of the 1921 flood are deep and ongoing. From the loss of life and displacement of that September to the decades-long negligence of racialized communities to the Olmos Dam and the creation of modern-day San Antonio, this torrent of water forever shifted the city. Like a stream that through the millennial-long process of erosion creates a canyon, so water has shaped and will continue to shape San Antonio—its politics, social structures, and geographies.

References:

https://digital.utsa.edu/digital/collection/p16018coll12/

Miller, Char, and Jeff Crane, editors. The Nature of Hope: Grassroots Organizing, Environmental Justice, and Political Change. University Press of Colorado, 2018.

1903 Topographic Map from the University of Texas at Austin Library

Olmos Dam, at night, San Antonio, Texas. Pub. by San Antonio Card Co., San Antonio, Texas, 1930.

Anam Mehta will graduate from Pomona College in May 2021, majoring in Environmental Analysis; he is also a fellow of the college’s Humanities Studio. His work on this storymap and other related research is funded through the Digital Humanities Program at the Claremont Colleges. Initial research was conducted in collaboration with Katie Graham and Natalie Quek, EA majors who graduated from Scripps College in 2019.