Jamaica floods, 2021- Forensic analysis

The UN Global Assessment Report on Disaster Risk Reduction (GAR 2024) report presents 10 case studies, each one with a forensic risk analysis, which systematically examines and investigates the disasters to understand their causes and impacts, as well as the effectiveness of any mitigation measures.

Step 1- Understanding the disaster DNA

What happened?

On January 8, 2021, heavy rains deluged Jamaica's Montego Bay, flooding roads and damaging vehicles and buildings alike. A total of 40mm of rain fell in a short period, affecting an estimated 933 people, including several injuries in the town. Montego Bay is home to a major cruise ship port, an airport, commercial centre, beach resorts, and golf courses.

The event was not unique in the sense that Montego Bay has experienced several major floods in the past decade, occurring roughly once every two years.

In November 2017, for example, 94mm fell within 4 hours, inundating the town centre, flooding businesses and sweeping cars away. At that time, floodwaters reached about 1.5 metres, affecting some 392 people and impacting critical infrastructure such as gas stations and Sangster International Airport.

Exposure: Where was damage concentrated?

These two floods in Montego Bay both affected business owners and residents. Floodwaters blocked main access routes to Sangster International Airport and major roads, with most damage occurring in low-lying areas.

Informal settlements were hit particularly hard, as debris-filled floodwaters clogged drains and flooded businesses such as banks, gas stations, supermarkets, shopping centres, and auto shops. Poorly constructed structures and household items were heavily damaged. These settlements, characterized by higher population densities and multiple houses in one yard, faced greater challenges in recovering and replacing damaged items.

Formal residences, mainly located on the town's outskirts, also experienced flooding. These households were marooned, and their properties and household items were damaged. Although structural damage was minor, the losses were significant.

Businesses, primarily located in the town centre, lost revenue but generally recovered more quickly. However, the loss of business directly impacted households who relied on those businesses as their primary income source. This was also true for the residents of informal settlements.

As Montego Bay continues to expand, including on marginal lands, flood risk remains a priority issue. Irregular settlements reflect social inequality, and authorities have not yet prohibited urbanization in high-risk areas or provided housing alternatives for those in informal settlements. Promoting affordable housing with safe, healthy spaces and easy access to work is essential to mitigating flood risks.

Vulnerability: Who was affected and why?

Tourism, Montego Bay's most important economic sector, was significantly affected. The 2017 and 2021 floods disrupted tourism by flooding hotels and blocking key roads. Many people from the informal settlements work in hotels, and the floods prevented them from going to work for several days or even weeks. The drainage problems also impacted tourism.

The floods mainly affected the poorer population, highlighting both the causes and symptoms of urban sprawl. Population growth and density increased pressure on the drainage infrastructure, especially near settlements on public lands close to parks and open spaces. When the rains came, garbage accumulated in public spaces, rivers and drains, contributing significantly to the flooding.

Limited research has been completed on the public health issues related to water and sanitation following the 2017 and 2021 floods.

Resilience: what factors limited the impacts?

Flooding events in Montego Bay are being carefully assessed to understand their impacts, and to develop strategies for better resilience against future floods. Challenges such as limited official resources for enforcing building codes and managing the many facets of unplanned urban sprawl, including maintaining debris-free drainage systems, underscore the need for meaningful inclusion of a variety of stakeholders.

Engaging local communities and businesses in meaningful ways is vital for effective governance. When governments and authorities properly connect with these groups to discuss the impacts of their actions and reach a shared agreement on the mindset and participatory actions required, then positive results can be achieved, sometimes surprisingly quickly. Meaningful inclusion is a vital part of avoiding disasters.

Despite the challenges of urban sprawl, Montego Bay is working to reduce its disaster risk through workshops, simulations, and community meetings. These activities build capacity and awareness, while bolstering preparedness and response capabilities at both political and operational levels. Hazard information is shared online and through products such as posters to educate residents about flood risks and other hazards.

Updating and enforcing the national building code and land use regulations are seen as vital. The proliferation of informal settlements along major drainage networks exacerbates flooding, as these settlements often obstruct the flow with accumulated waste. Aging drainage infrastructure further compounds the issue, particularly as urban expansion introduces new tributaries without corresponding upgrades.

Local authorities clean the main drains to mitigate flood risks, but improper waste disposal in informal settlements hinders these maintenance efforts. Debris accumulates on beaches and in ports, detrimentally impacting coastal ecosystems.

Public consultations, research studies, and assessments involve diverse stakeholders such as NGOs and vulnerable community residents. Regulatory frameworks mandate environmental impact assessments for proposed developments in sensitive coastal areas. Hazard information is incorporated into land use planning and environmental protection strategies. A squatter management unit collects and analyses data on informal settlements.

Enforcement remains an issue on marginal lands throughout Montego Bay, but the accelerating expansion of informal settlements is driven by the demand for work and increased access to amenities. While the housing needs of informal settlers are evident, there is not enough land available to build housing with easy access to employment and services in the town. Most land on the outskirts of town is privately owned, with some housing developments for middle and high-income earners.

Restrictive measures should be put in place for construction in areas where the flood threat is identified as high or very high. Developing policies, regulations, codes and other instruments that support stronger governance around territorial planning is a key element in reducing flood risk.

To the extent possible, enforcement of laws to control littering and improper dumping can be improved, with an emphasis, for example, on fines for violations. Effective solid waste disposal strategies can also be promoted in communities through education and public awareness. Periodic cleaning of creeks and ravines should continue, and drainage networks in and around the city should be improved.

Step 2- Future trends

This section looks at key root causes or emerging issues identified above and provides a snapshot of potential 'business and usual' trends where action now could prevent or reduce disasters in the future.

People

• Jamaica is the 35th most densely populated country in the world, with 2.9 million people living in an area of 10,991 square kilometres. Montego Bay, a key town, has a population of 110,000. The percentage of Jamaica's population living in urban areas is set to rise from 56.3 percent in 2020 to 62.8 percent in 2035. In 2011, just 14.5 percent of the population was connected to sewerage. Some 46.4 percent of the population live within walking distance to public transport.
• Jamaica ranks among the top three most exposed countries in the world to multiple natural hazards. It has the second highest economic risk exposure to two or more hazards, with 96.3 percent of its GDP at risk. The areas most exposed to and least equipped to deal with hazards such as floods and hurricanes are along the coast, where most of Jamaica's capital towns are located. Unplanned settlements in environmentally sensitive lands, such as flood plains and unstable slopes, increase the risk of natural hazards becoming disasters and the levels of damage possible.

Planet

• The IPCC's Sixth Assessment Report (AR6) expects global mean sea level to rise between 15 and 23 centimetres by 2050 in a very low greenhouse gas emissions scenario. Without shoreline defences, under a worst-case warming scenario by the end of the century, 5 percent or more of Kingston, Jamaica is projected to fall permanently below sea level.
• The estimated per capita waste generation is currently an estimated 1.2 kg/day per person, and this is expected to increase to 1.5 kg/day due to factors such as population growth and changing consumption patterns. Pollution is widespread and illegal dumping is commonplace in some communities. Large volumes of waste are dumped in gullies and rivers, which lead to flooding and pollutants in marine environments. Air pollution is affected by emissions from the transportation sector and well as from burning of waste.
• In 2018, Jamaica launched its Beating Plastic Pollution Campaign, part of a global initiative, to address the challenge of plastic bags, plastic bottles, microbeads, styrofoam, and more, which fill Jamaica's streets, gullies, and harbour.
• Coastal ecosystems face escalating degradation due to projected urban expansion which could intensify flood risks.

Prosperity

• Recurrent flooding is projected to impact tourism, infrastructure, and livelihoods.
• Inaction on improving drainage infrastructure and implementing robust urban planning measures is expected to exacerbate economic vulnerabilities and hinder sustainable growth estimated at 1.6 percent if climate resilient infrastructure is implemented.

Step 3- Forensic learning

This section aims to encourage dialogue around the forensic analysis to foster improved decision making. The areas for consideration below are envisaged as an input to stimulate in-country discussion and action plan on future disaster prevention and enhanced disaster risk management