Chapter 1: The Flooding Crisis in Mexico City

Mexico City has long struggled with flooding, highlighting a critical truth: engineering doesn't necessarily solve issues but often reshapes them.

On July 15, 1951, Mexico City faced a catastrophic flood, reminiscent of previous calamities. Following torrential rains, sewage systems overflowed, inundating vast areas of the city with polluted water. The aftermath was captured in striking photographs of boats navigating through downtown, marking a significant failure in urban planning. The Grand Canal, hailed as a cutting-edge drainage solution, proved ineffective, leaving residents to wade through the water to reach their destinations.

These dramatic incidents are how the public typically views technological failures. However, many failures, particularly regarding environmental challenges, are less visible and unfold over time. Scholar Rob Nixon refers to this as "slow violence," a phenomenon that disproportionately impacts marginalized communities and often goes unnoticed by those in power. As a result, technologies may appear successful until their shortcomings are dramatically exposed.

The ongoing flooding issues in Mexico City serve as a cautionary tale amid the looming threat of climate change. There is a risk that we may again rely on technological quick fixes from Silicon Valley, ignoring the complexities and potential consequences. These solutions often seem effective, at least for those in positions of privilege, but they can lead to unforeseen burdens on others and future generations.

Section 1.1: The Sinking City

The 1951 flood was officially attributed to obstructed drains; however, engineers recognized a deeper issue: the city was sinking, compromising its drainage capabilities. By the 1940s, experts like Nabor Carillo had established that this sinking was man-made. The rapid urban expansion led to excessive groundwater extraction, causing the clay-rich lakebed to shrink and resulting in significant land subsidence.

This subsidence severely affected the Grand Canal, designed in the early 1900s to alleviate flooding by channeling rainwater and sewage. Mexico City, situated in a closed valley without natural rivers, depended on this canal. However, as the city sank, the canal's effectiveness diminished, leading engineers to fear that it would eventually direct water toward the city rather than away from it.

To mitigate future flooding, post-1951 engineers implemented two key changes: relocating groundwater wells to the urban outskirts and developing a radical deep drainage system to manage the city's excess water.

Subsection 1.1.1: The Deep Drainage System

The Deep Drainage System (Sistema del Drenaje Profundo) aimed to transport water from the city's center, utilizing gravity to direct it under the mountains to the Valle de Mezquital, where it could irrigate crops. This ambitious project, completed in 1975 after extensive planning and construction, became a symbol of success for the government, which celebrated its completion with grand announcements and media coverage.

The system has since expanded, now functioning like an unseen subway network that supports the city's growth by preventing catastrophic flooding in the downtown area. However, this perceived success has come with significant consequences.

Chapter 2: The Hidden Costs of Flood Protection

Despite its effectiveness in flood prevention, the Deep Drainage System has led to a rapid decline in the city's groundwater levels, particularly affecting those living in the urban periphery.

The first video, "How Engineers Solve Problems," discusses the complexities and challenges faced by engineers in urban environments. It emphasizes the importance of understanding the broader implications of engineering decisions.

As the system pumps groundwater and imports water from distant sources, it exacerbates water scarcity, particularly for impoverished communities that struggle with inconsistent access. In neighborhoods like Iztapalapa, residents often face long waits for water delivery and must resort to purchasing bottled water for basic needs.

The consequences of subsiding groundwater levels are compounded by structural issues in the city's sewer systems, which have become increasingly vulnerable to flooding during storms. The problems are not uniformly distributed; wealthier areas are often protected at the expense of poorer neighborhoods, leading to a patchwork of flooding that remains largely invisible to decision-makers.

The second video, "Problem Solving Steps for Engineers and Students!" explores strategies for effective problem-solving in engineering, stressing the importance of considering social and environmental impacts.

As the city continues to grow, the Deep Drainage System faces increasing pressure, leading to difficult decisions about which areas to flood in order to protect others. This dynamic reveals the deep inequities in how urban infrastructure is managed and maintained.

Conclusion: Rethinking Engineering Solutions

The experience of Mexico City's flood protection systems teaches us a vital lesson: engineering often transforms problems rather than solving them. The narrative of success can obscure the ongoing challenges that emerge as a result of technological interventions.

We must critically assess our reliance on engineering as a panacea for complex issues, recognizing that each solution can create new challenges. In doing so, we can strive to build a more equitable future where the voices of all communities are heard in the decision-making process.

The perception that engineers merely "solve problems" can lead to dangerous oversights, allowing policymakers to pursue unsustainable growth while ignoring the underlying issues that persist. To avoid repeating past mistakes, we must engage in collective deliberation about the implications of our engineering choices and prioritize sustainable solutions that genuinely serve all members of society.