Cities, like any area where population densities peak, are hot spots for the spread of epidemics. This is even more pronounced in those that attract many rural-urban commuters. Or in international travel destinations. Clearly, if we are to control the spread of COVID-19, any countermeasures must focus on restricting some aspects of cities and their connectivity.

Unfortunately, such measures will hit the central nerve systems vital to urban resilience. Much more than rural villages, the urban metabolism depends on its surrounding region for key resources, such as food and water. This dependence puts locked-down cities across the globe under risk.

We have seen similar situations when supply chains were affected by political or economic crises, or the increasingly common impacts of extreme climate events. As much as water matters, urban food supply will also prove challenging, given the complexity of different food source areas and formal and informal food supply systems. And the vulnerability of these varies greatly among commodities.

The International Water Management Institute (IWMI), through the CGIAR Research Program on Water, Land and Ecosystems (WLE) works on strengthening ‘rural-urban linkages’, aiming to make urban food systems more resilient to shocks and stresses.

One of the solutions, studied in collaboration with the Food and Agriculture Organization of the United Nations (FAO) and the Global Partnership on Sustainable Urban Agriculture and Food Systems (RUAF), is to ensure cities in Africa and Asia can understand where their urban food supplies are vulnerable. We do this using a common international methodological and indicator framework, which measures data like the strength of distribution chains for particular sectors or commodities, health and food safety aspects, or how much food is being wasted. Policy dialogues and capacity development help ensure city regions can use the tools.

To give an example, we studied the dependence of urban centers on their ‘hinterland’ over several seasons for more than 50 commodities in several cities in West Africa. According to an analysis of more than 40,000 records of food ﬂows for two cities, about half of basic urban food needs were met by farming within a distance of 100 km. Extending to 300 km, 80-90% of all food items were sourced for Tamale, Ghana and 60-80% for Ouagadougou, Burkina Faso. In comparison, the average processed food item found in shops and supermarkets had traveled 3,700 km before reaching local shelves. On its way, food flows are facing more human barriers than expected, as a recent IWMI/WLE supported study in West Africa showed.

Interrupting rural-urban linkages can have stark impacts on food prices – and thus on the poor. In Asia, Sri Lanka’s largest city Colombo is facing such a situation. While under the COVID-19 threat, traffic between districts is completely banned across the country, except for essential services, even this was not possible four years earlier after Sri Lanka was hit by a cyclone that caused severe flooding, storm surges and landslides. Colombo’s supply of vegetables coming from upcountry were seriously affected. Vegetable prices quadrupled, while ocean fish supply dropped by 75%. The mainstream supply chains, which serve the middle- and low-income communities, needed up to two months to recover.

The vulnerability of various production systems and likely bottlenecks along the supply chains demands specific investments. And this is a global issue. Even before COVID-19, 70% of cities were already at risk of – or already dealing with – effects of climate change and related anomalies challenging urban resilience.

A common recommendation for less vulnerable rural-urban regions is promoting cultivation within and near the city. This can make a significant contribution to urban food supply by providing commodities that are important for a balanced diet. For example, IWMI studies show that irrigated urban agriculture could produce as much as 90% of the leafy vegetables consumed in a city, particularly in Africa.

In Cali, Colombia, our WLE partner, the International Center for Tropical Agriculture (CIAT) supported an urban food policy which includes seeking ways to create shorter supply chains, so that food reaches the final consumer cheaper and in better quality. Neighborhood shops, mobile markets, and school gardens will be supported to provide quality vegetables at affordable prices. These new systems will help Cali endure broken city-region linkages, whatever the causes.