Water Shortages in Latin America: How Can Behavioral Science Help?

Antanas Mockus was the mayor of Bogota between 1995 and 1997. I was just a kid back then, but I remember how several of his communication strategies to tackle citywide issues like jaywalking and traffic accidents made him a celebrity. Today we would call them social norm-based programming or “nudges,” but back then this innovative approach was called citizenship culture. The best example demonstrating Mockus’s citizenship culture approach to collective action was his voluntary water-saving campaign.  

Water consumption in Bogota had been rapidly increasing since 1940 due to rapid population growth.⁶ Excess demand and a tunnel collapse in the San Rafael reservoir heightened this supply crisis.⁷ The media and policy experts were calling for a municipal rationing. However, Mockus thought that citizens could collaborate voluntarily to save water and avoid rationing, helping to ease the shortage until the tunnel was repaired. Skeptical, the press and experts did not think this was possible. Still confident, Mockus launched his consumption reduction campaign, and the initial results were disastrous: water consumption actually increased during the first week. Much like today! Were the press and experts right all along?  

No, they were not! Spoiler alert: Mockus’s campaign eventually succeeded! How? Here are a few lessons from back in the ‘90s that Bogota and other Latin American cities today could benefit from for mitigating water shortages.

1. Gather evidence

The government started by surveying citizens to understand the reasons for this increase in water consumption. They found that citizens filled water tanks in anticipation of cutbacks because they distrusted each others’ ability to save. In addition, 90% of citizens tried to save water but did not know how to do so effectively. For example, most reported saving water through smaller actions such as brushing their teeth with the faucet turned off. Almost no one saved in high-consumption activities such as taking showers, washing clothes, or flushing the toilet. Behavioral analysis allows us to actually understand the root cause of the issue, and thus, make the changes that count!

2. Provide constant and timely feedback on the desired behavior 

Mockus and his team pivoted their strategy based on the new evidence and designed a series of interventions to promote voluntary water saving. For instance, in partnership with the local newspaper, they published a daily report on the previous day's water consumption to keep citizens informed about how their actions were directly contributing to the results. 

3. Showcase the early adopters 

The newspapers also published citizen testimonials to show how others were already saving. For instance, imagine seeing a picture of Santiago, his age, and a quote on how he has been reusing the water he collects in a bucket when showering to flush the toilet. 

There are two key aspects here that we could apply today: timely feedback on the desired behaviors and changing social expectations about the empirical norms at play. Simply put, to address a collective action problem, show that people are already doing it! That way, the rest will feel like they’re falling behind, increasing their chances of adopting the behavior to feel like they belong to the community. 

4. Informed and culturally relevant nudges

To truly invest in the community’s interest, the Bogota government repurposed a local symbol of Archangel San Rafael—the namesake of the depleting water reservoir—to communicate water-saving strategies. This way, citizens could understand the cultural importance of these strategies with a religious holy card posted in their homes (which worked pretty much like a nudge!). Bogota also employed more than 4,000 volunteers on foot called the “aquacívicos,” who handed out information and flyers on saving strategies. Finally, the mayor even took a public shower with media coverage exemplifying sustainable habits by turning off the tap to lather up.⁷

The results: water consumption decreased by 14% in a few weeks and from 18 to 16 cubic meters during the next two years following the campaign.⁶  

Beyond the lessons from Bogota in the ‘90s, more recent developments in behavioral science can inform interventions to reduce individual water consumption. Here are just a few!

1. Gamification: Local governments have integrated game design mechanics into water-saving to turn it into a competitive challenge, where residents can earn prizes and rebates for reducing their usage.
2. Tiered Water Pricing: Some municipalities have adopted tiered pricing structures where the cost per unit of water increases as the quantity of water used goes up. This financial incentive structure encourages people to use less water to avoid higher bills.
3. Rainwater Harvesting Incentives: To promote sustainable water use, some municipalities have offered incentives such as rebates, tax reductions, and even technical support for installing rainwater harvesting systems. In a city historically considered “rainy” like Bogota, the local government could leverage this incentive to rely less on their reservoirs.
4. Targeted messaging: Unlike back in the ‘90s, Bogota today has poorly communicated its reduction strategies. For example, I’ve read reporting targets in cubic meters, a measurement harder to understand for consumers compared to others such as liters. I also found advice on an official Bogota Water Management website about pouring a glass of water on your nightstand as a water-saving strategy—which, unless you go to drink heavily from the tap every night, doesn’t address the problem effectively. 

This means that to make real impacts, we need to identify the changes that count. According to Bogota’s Water and Sewerage Company, 58% of water consumption is rooted in personal hygiene.⁸ For instance, Bogotanos love taking showers. Colombia and Mexico are among the countries where people shower most often in the world! Imagine being told you should not shower daily when it’s a habit for over 95% of the population and a well-established social norm. You need to learn how to communicate that change effectively—in a culturally relevant way!   

TDL achieved just this in helping the City of Rome alert its citizens of an upcoming diesel ban—which, although necessary for the environment and local health, would put a big damper on their daily lifestyles. Rather than informing citizens they’d have to stop driving their cars in large swaths all over the city, we framed our campaign around the best reasons for them to do so: preserving the historical sites that make them proud to be Roman and taking care of their families. Put simply, we aligned our messages with their values. You can read more about our work here. 

We know that gathering evidence to inform interventions, providing constant and timely feedback on desired behaviors, showcasing early adopters, and nudging people in a culturally relevant way has worked in the past. Moreover, innovations like gamification, incentivizing rainwater harvesting, and innovative pricing have helped more recently. 

Sadly, water scarcity at the municipal level is not going to improve unless we do something about it. Any city not engaging in cultural change around water consumption is lagging behind. Hopefully, looking to the past and the present will provide us with a set of tools to foster collective action in a city looking to reduce water consumption in the future.