Background

Climate change is a key driver of the increasing number of extremely hot days and heatwaves already experienced and projected for Gauteng. This is compounded by dense concrete structures, vehicles, and appliances in a rapidly urbanising region.

Areas with limited green spaces fare far worse than those with tree cover and vegetation. Heat across areas in Gauteng is distinguished by, in instances, significant differences. Some neighbourhoods are up to 6°C hotter than nearby rural areas.

As an example, in the City of Johannesburg, the maximum temperatures per day for seven other stations have been compared with those of Braamfontein, with Orange Farm having the highest maximum temperatures. Projections suggest that by 2050, the number of hot days per year could increase six-fold, posing significant challenges for city leaders in managing health, economic stability, and infrastructure resilience.

The Council for Scientific and Industrial Research (CSIR) and the South African Weather Service define heatwave days as those with maximum temperatures exceeding the average maximum temperature of the warmest month of the year at that location by 5 °C, for a period of at least three consecutive days.

Metropolitan municipalities in Gauteng, namely the City of Johannesburg, Ekurhuleni and Tshwane, have acknowledged this threat and taken initiative to incorporate extreme heat mitigation into their climate action plans and core city operations and budgets.

Recent efforts in the three Metros, in which Planact has played a key role, have engaged more than 150 local citizens in on-the-ground heat data collection and conducted computer-based climate modelling. Various peer learning workshops, led by the World Bank and partners, were held in 2023 and 2024 to share lessons on heat mitigation measures. This culminated in an agreement to implement heat action plans.

Gauteng City Region Heat Action Plan and Early Warning System

Planact is currently part of the Gauteng City Region Heat Action Plan (HAP) and Early Warning System (HEWS) Working Group led by the World Bank’s City Resilience Program, with collaboration from the National Treasury’s City Support Programme, the Global Facility for Disaster and Recovery, and support from the Swiss State Secretariat for Economic Affairs.

Objectives

The objective of the working group is to develop a comprehensive HAP and HEWS for the Gauteng City Region, integrating short and long-term interventions to address heat-related risks. This includes fostering collaboration among municipal departments, civil society, and technical experts to ensure preparedness, response, adaptation, and recovery measures for extreme heat events. Heat Action plans combine assessments and actions as a response mechanism to heat-related impacts.

Technical Working Groups

The World Bank is convening a series of five technical Working Group workshops to design and shape Gauteng’s HAP and EWS. Three have already taken place in total. The first workshop held was on inter-agency response protocols and defining institutional roles and actions before, during, and after heat events. In group exercises, robust matrices were developed by four separate teams, outlining responses according to heat seasons, and the lead and support agencies.

The pre-heat season is characterised by heat mapping and data collection, Standard Operating Procedure development, Joint Operations Centre activation, training, awareness raising, centralised communication strategies, mobilising resources and policy and regulatory adjustments, among other actions. During the heat season, various responses are triggered by a range of agencies and actors, one of which is the activation of medical and public health services.

These include extending clinic and emergency service hours, training healthcare workers to identify and treat heat-related illnesses, stocking essential medications, and establishing mobile medical units in areas with vulnerable populations. Public awareness and effective communication messaging are vital at this stage, along with physical interventions, such as shading and cooling options, and a reliable water supply. Emergency response teams are directed to high-risk zones, and flexible school hours are implemented. Monitoring and evaluation, as well as learning, are strong aspects of the post-heat phase, as well as the effectiveness of response mechanisms such as the JOC.

The second technical Working Group session on Public Awareness and Community Outreach focused on designing clear, practical, and medically informed public health advisory messages and awareness campaigns. The aim is to drive behaviour change among vulnerable groups and those living in high-risk settings through targeted messaging, seasonal campaigns, and a coordinated communication strategy. Special outreach approaches for groups most at risk (elderly, children, outdoor workers, people in informal settlements, those with chronic illnesses) are also required by a range of actors.

The session served to underscore the importance of impactful communication that meets people where they are, whether on WhatsApp, at clinics, churches, or through murals and mobile outreach. To be truly effective, campaigns must be informed by local realities, delivered by trusted messengers, and tailored to specific audiences. Proposed delivery mechanisms ranged from WhatsApp and community radio to clinic posters, youth ambassadors, and even animated mascots and ringtones.

The emphasis, across all groups, was on simplicity, accessibility, and multilingual communication. Throughout the day, a strong message emerged: awareness campaigns must do more than inform – they must empower. To do that, responses must be co-developed with the communities they aim to serve, reflect lived realities, and be conveyed in ways that inspire action. The ideas and practical input will directly inform the development of a Heat-Health Messaging Toolkit.

This third, in a series of technical Working Group sessions, focused on strengthening the health system’s ability to respond to extreme heat events. It explored how to equip healthcare facilities, address the training needs of healthcare workers, and develop protocols to ensure the health system is prepared to manage heat-related impacts.

Early Warning Systems

Early Warning Systems are vital in building an effective and timely approach to addressing the risks arising from heat events. Developing and using weather forecasts to predict heatwaves is imperative, as well as issuing timely alerts to government agencies, health services, and the public.

Inter-agency coordination and clarifying the roles and responsibilities of different government departments, including health, disaster management, water, housing, public works, and others, is central. Effective heat action response will also require national, provincial, and municipal responses and coordination, encompassing policy, regulatory processes, financing, and support responses.

Long-Term Urban and Environmental Strategies

Over the long term, a range of more enduring but deliberate responses by municipal actors and others, importantly, communities will need to focus on, amongst others.

• Expanding green cover, including tree planting, and cool roofs to reduce the urban heat island effect.
• Wetland restoration to regulate temperatures.
• Improving access to water and sanitation.
• Encouraging climate-resilient urban planning and housing.

The way our cities manage heat, in the months and years ahead, will determine how safe, equitable, and sustainable they are in the future. Prioritising effective climate change action is not an option, but it will be key to ensuring the building of more adaptive and resilient neighbourhoods that foster thriving communities.