Contagem: Energy & Nature Hand in Hand

Contagem, a major city in the Belo Horizonte Metropolitan Region, is advancing innovative climate actions that combine clean energy with nature-based solutions (NBS). By installing solar photovoltaic systems on municipal buildings and creating rain gardens in flood-prone areas, the city is cutting emissions, enhancing biodiversity, and improving resilience to climate change. These initiatives demonstrate how mid-sized cities can deliver dual mitigation and adaptation benefits while fostering well-being, climate justice, and environmental stewardship.

The implementation followed a phased, integrated approach:

1. Baseline assessment – Mapping of flood-prone neighborhoods and energy consumption patterns across municipal buildings. The city identified priority schools, administrative offices, and cultural facilities for solar PV deployment.
2. Design and planning – Technical designs of rain gardens were developed under the INTERACT-BIO framework with ecological input from academic partners. Public buildings were audited for solar rooftop potential.
3. Pilot installation – Initial rain gardens were established in flood-prone streets and near public spaces, designed to capture runoff, filter water through vegetation, and allow infiltration. At the same time, solar panels were installed on selected public buildings with monitoring systems for energy output.
4. Community engagement – Local residents were consulted and trained in the maintenance of rain gardens. Workshops emphasized co-benefits like reduced flooding, improved safety, and lower electricity costs for city services.
5. Scaling & integration – The city began combining rain gardens with other green-blue infrastructure such as retention ponds and terraces, while expanding solar PV coverage to more municipal buildings. Plans are underway to integrate co-use approaches—such as solar-powered pumps linked to urban gardens and solar lighting in green spaces.

This robust, stepwise approach allowed Contagem to test feasibility, adapt to challenges, and scale solutions in a cost-effective manner.

Collaboration across levels of government, NGOs, and communities ensured successful implementation.

• Municipality of Contagem (project lead and implementation)
• INTERACT-BIO project (ICLEI, GIZ, EU support for design and capacity-building)
• Local universities and experts (ecological and technical design)
• Community organizations for awareness and maintenance activities

Contagem prioritized citizen involvement to build ownership and awareness.

• Information campaigns on climate risks and solutions
• Demonstration sites at schools and municipal buildings to showcase solar and rain gardens
• Community workshops on maintenance and biodiversity benefits
• Engagement of local media to highlight co-benefits for health and climate justice

A blended financing model made the projects feasible.

• EU Horizon / INTERACT-BIO programme: €2 million
• Municipal government funding: €0.5 million for installation and co-financing
• In-kind resources: Land allocation, technical staff time, and local community contributions

Contagem’s combined energy and nature initiatives have already delivered measurable benefits across multiple dimensions. The installation of solar photovoltaic panels on municipal buildings now generates around 1,205 MWh of renewable electricity per year, avoiding an estimated 40 tonnes of CO₂ emissions annually and reducing the city’s energy bills. At the same time, the rain gardens have cut stormwater runoff by more than 10% in pilot zones and improved groundwater recharge by up to 25%, helping to reduce the severity of floods during the rainy season.

These green infrastructures have also created new microhabitats, contributing to a rise in local biodiversity indicators and improved air quality. Beyond environmental gains, the initiatives strengthen climate justice by protecting vulnerable neighborhoods, improving public health, and creating more livable spaces. Together, these outcomes demonstrate how integrated energy–nature solutions can multiply benefits, combining climate mitigation, adaptation, and social well-being in a cost-effective way.

Contagem overcame significant challenges to achieve results.

• Limited technical capacity initially for integrated project design
• Institutional silos between departments (energy vs. environment)
• Ongoing maintenance needs for rain gardens
• Dependence on external funding for initial investments, raising questions about long-term financial sustainability

Contagem’s experience offers a powerful model for replication in other mid-sized cities. The combination of nature-based flood management and solar PV on public buildings is transferable and can be tailored to diverse contexts. Key lessons include: the importance of community involvement, cross-departmental governance, and leveraging international funding blended with municipal resources.

In conclusion, Contagem demonstrates that the twin transition of clean energy and nature-based adaptation is not only possible but also beneficial for citizens. By tackling emissions and flood risks simultaneously, the city achieved co-benefits across health, biodiversity, and equity. Other cities can learn from Contagem’s phased approach, ensuring that climate neutrality and resilience go hand in hand with social well-being.

• ICLEI INTERACT-BIO Project
• Contagem – City information ICLEI
• UTMC Policy Brief : Synergizing Urban Energy and Nature

Secretariat for Environment and Sustainable Development
Municipality of Contagem
semad.gabinete@contagem.mg.gov.br