By Thomas Boynton and Madeline Flynn
- Population booms and climate change are changing the dynamics of effective urban water security
Cities, since their inception, have always been confronted with challenges of water security; however, over the last decade, there have been worrisome instances of water security threatening modern cities in their entirety. In 2014, lead poisoning from contaminated drinking water threatened the city of Flint, Michigan, impacting 95,000 residents and costing approximately $400 million to address. The crisis, caused largely by a decision to change water sources and to lower chlorine levels, took 5 years to resolve, and its public health impacts still burden residents. In 2018, Cape Town, South Africa was almost the first major modern city to run out of water, brought on, in part, by an extraordinary three-year period of low rainfall. Preventing these sorts of challenges in the future necessitates reflection on core concepts of urban water security. The recent water crisis afflicting Houston, Texas in early 2021 serves as a case study for such reflection. To successfully evaluate Houston’s water crisis, the urban water security field merits introduction.
Until recently, urban water security has received little attention from academics and practitioners alike. Partly due to the complexity surrounding water management, and the fact that urban water security is an emerging field, discussions of urban water security understandably suffer from terminological confusion and inconsistent applications. For instance, does water security relate simply to the resource, or does it also encompass supplying the resource? Is it a quantifiable threshold or a policy direction? Similarly, how do we define ‘urban’? Where does the urban end and the rural start - the distinction quickly blurs as we begin to consider megacities and urban sprawl. Regardless of the answers to these questions, the urban catchment is quickly becoming the ‘new frontier’ for water security challenges.
On Sunday, February 14, 2021, the entire state of Texas was under a Winter Storm Warning. Due to frigid temperatures, freezing rain and snow, at one point, more than 800 public water systems serving 162 of the state’s 254 counties were disrupted, affecting 13.1 million people. The extreme weather conditions caused power outages, which lasted for weeks for some Houston residents, and had detrimental impacts on the city’s water supply. Houston relies on pumps to generate water pressure, and during the winter storm, freezing temperatures prevented backup generators from turning on during the power outage. Treatment plants were also running below capacity, in part because the chemicals used to purify the water were not behaving normally, which is also likely due to the freezing temperatures.
On February 16, Houston temperatures dropped to -10 degrees Celsius, a record low temperature last recorded in 1895. The next day, February 17, the entire city of Houston issued a boil water notice. In Harris County, which includes Houston, more than one million people were affected by local water systems that either issued boil notices or that could not deliver water at all as pipes leaked and broke, and wells froze. The combination of the city’s loss of power and the boil notice had dire consequences on local residents. To address sanitation concerns at a hospital in Houston, water was hauled in on trucks to flush toilets. Houston lifted its boil water notice on February 21, but thousands of homes still have no running water because of broken pipes.
Houston’s water crisis provides three takeaways for the field of urban water security. First, the case study of Houston’s water crisis highlights the potential scale of threats posed by urban water security challenges. The water crisis facing Houston was not confined to a particular area of the city, as boil advisories and water shortages occurred throughout. Houston demonstrates the integrated nature of urban water supply networks and highlights the importance of taking a city-wide integrated spatial analysis to water security planning. The sheer number of people affected by this crisis is worth noting. Houston is Texas’ largest and the nation’s fourth-largest city, hosting a population of over 2.3 million. The high concentration of individuals living in urban areas, now and in the future, necessitates that water supply to cities works, and works well. Roughly 50% of the world’s population live in urban areas, and by 2050 the proportion is expected to reach over 70%. Consequently, urban water security is only going to become increasingly more important.
Second, Houston demonstrates how urban water management inevitably means managing more than just water. Power outages and the inability to boil water constituted as the driving force behind Houstonians lacking access to adequate and safe drinking water. Urban water security is tied to a city’s infrastructure network, including gas and electricity. Water security will be best achieved when relevant regulatory and institutional bodies successfully collaborate in an integrated manner reflective of the very nature of the problem. Houston’s water crisis demonstrates the important need for cross-sectoral communication and for regulatory officials to take a holistic approach to urban water management.
Third, Houston offers insight into issues of uncertainty driven by climate change that threaten the urban catchment. The exact ways in which climate change is set to manifest in local areas are difficult to predict and highly contested. However, a wide array of predictions point to a resulting increase in the frequency and severity of extreme weather events like unexpected and rapid freezing, similar to the weather, which caused the electrical and water issues in Houston. As extreme weather and natural disasters increase in both frequency and intensity, public infrastructure management must be able to adapt. Doing so will require city officials and water managers to incorporate climate ‘extremes’ into their risk assessments in order to effectively create a resilient framework for urban water security.
Learning from modern urban water security challenges, like the historic freeze that hit Houston, offers the opportunity to explore and refine the best practices for creating and adapting city-wide water management strategies. Ultimately, the best efforts for addressing this new frontier will appreciate both local contexts and the inherent uncertainty of climate change to encapsulate the full risk facing the urban catchment.