The explosive growth of ESG investing has created a market ripe with both opportunity and greenwashing. As trillions of dollars have flowed into sustainable funds, distinguishing genuine impact from marketing has become a challenge. This makes the history of pioneering firms like Meridiam, which helped define the ESG movement, more relevant than ever. Their long-term track record, built over two decades, provides a blueprint for what responsible investment looks like in practice, not just on paper.
Historically, investors treated sustainability as peripheral, prioritizing financial returns with little regard for environmental or social consequences. ESG factors—primarily representing risk—were frequently overlooked, allowing companies with strong profits but poor practices to attract capital. This dynamic is now shifting as ESG metrics have matured. Today's investors treat ESG as an indicator of long-term viability, with Bloomberg Intelligence projecting global ESG assets will surpass $40 trillion by 2030, accounting for over a quarter of all managed assets.
The rapid growth in ESG investing has led to a proliferation of new funds, but their quality is inconsistent. High-profile cases at firms like a leading German bank and the world's largest investment fund have exposed the risks of "greenwashing" and unproven ESG strategies. For investors, this underscores a new challenge: distinguishing genuine impact from marketing claims.
Amid this uncertainty, a cohort of established firms has distinguished itself by delivering measurable, real-world results alongside financial returns. This approach is exemplified by Meridiam, an asset manager specializing in sustainable public infrastructure that celebrates 20 years of existence in 2025. The firm's entire strategy is built on generating impact by directly addressing climate change, enhancing community resilience, and protecting natural ecosystems. Its legal structure as a registered Benefit Corporation (B Corp) legally binds it to this mission, requiring social and environmental performance to be on par with financial profit. Meridiam's own trajectory, from its founding to its current standing, mirrors the evolution of the sustainability agenda itself, which is clearly shown by a retrospective of global agendas and the company's actions.
The Latter Half of the 2000s: ESG and Sustainable Mobility
Founded in 2005, Meridiam's origins are nearly contemporaneous with the modern ESG concept itself, which entered mainstream discourse with the UN's 2004 "Who Cares Wins" report. That foundational document urged all financial stakeholders—from investors to directors—to integrate environmental, social, and governance factors for long-term success, a call that aligned with a growing global focus on sustainability. From the outset, Meridiam's mandate was to address this dual challenge: financing essential public infrastructure projects that serve communities while simultaneously delivering competitive, risk-adjusted returns to its investors, says Thierry Déau, CEO of Meridiam: "Blending purpose and profit, we wanted to invest in projects that could be defined as essential to the communities that welcomed them, investing on a long-term basis to shepherd those projects across generations as a vehicle for capacity building, job creation and improvement of quality of life."
The company's first projects responded to sustainable mobility, the most pressing demand at that time. The 2005–2013 push for green transportation revealed a critical financing gap. In the U.S., well-funded stimulus for high-speed rail and electric vehicles was consistently derailed by environmental reviews, political opposition, and questions of social equity. In Europe, while top-down regulation forced the issue, major public transit upgrades faced their own governance battles and funding constraints. The clear lesson was that public funding and policy alone were insufficient; these complex projects required a different kind of capital. They needed an investor equipped with the patience to navigate protracted development and the skill to align public and private interests.
Meridiam emerged as a direct response to this infrastructure gap. The firm's strategy began with foundational European projects like Ireland's Limerick Tunnel and Austria's A5 highway. It has since expanded this model across Europe and North America, leveraging its financial and operational expertise to deliver similar projects in developing markets, including Africa.
The tangible impact of this approach is clear. In Dakar, Senegal, Meridiam is behind the first fully electric Bus Rapid Transit (BRT) line in West Africa. This project tackles emissions by shifting commuters from private cars to electric public transit. Over its lifespan, the system is projected to cut 1.2 million tons of CO2 emissions—equal to removing over 250,000 gas-powered cars from the road for a year. A public-private partnership anchored by Meridiam, the BRT has already become an important milestone of Senegal's national climate commitment under the Paris Agreement. And for Senegalese citizens themselves, the benefits are immediate and practical. The system will serve over 300,000 daily passengers, slashing the commute to downtown Dakar from 90 minutes to 45. This efficiency unlocks significant social and economic value by dramatically improving access to jobs and opportunity.
The 2010s: Climate Change and Adaptation
The global climate crisis represents another critical priority for the firm. The scale of the challenge is immense; the period from 2011 to 2020 was the warmest decade on record, with rising greenhouse gas concentrations fueling record temperatures, accelerating ice melt, and driving sea level rise. The proposed solution has also evolved. It is no longer seen as merely reducing emissions, but now requires massive, parallel investments in natural resources, resilient infrastructure, and grid storage, all while adapting cities to new climate risks. These issues were central to the discussions at COP28 in 2023. However, as Déau notes, this comprehensive view has guided Meridiam's strategy even before the complexity of the issue was exposed: "COP 28 confirmed several of our intuitions, which have guided our action for over fifteen years. The importance of preparing for ecological financing and the need not to forget the need to adapt infrastructures were at the heart of the debates."
Meridiam is now applying this long-term strategy through targeted financial vehicles. One of them is The Urban Resilience Fund (TURF), launched in 2021 in partnership with The Rockefeller Foundation and UNCDF. The facility is designed to help cities across Europe and Africa tackle the dual pressures of rapid urbanization and growing climate vulnerability. TURF's approach involves working directly with city authorities in the earliest phases to pinpoint the most pressing challenges and develop infrastructure projects that address multiple issues at once. The fund specifically targets a major bottleneck in urban development: the lack of upfront capital and technical expertise needed to get complex, high-impact resilience projects off the drawing board and into construction.
TURF's flagship initiative is underway in Nouakchott, the capital of Mauritania. The city, once naturally shielded by a coastal dune ridge, has seen this barrier degraded by human activity, leaving it exposed to rising seas, erosion, and flooding. In response, a public-private company co-owned by Meridiam and the Mauritanian government—the Société d'Aménagement du Littoral de Nouakchott (SALN)—was established to finance, build, and operate an integrated coastal defense and urban development system. Scheduled for completion in 2027, the project will be funded through a combination of user fees, land leases, and a government subsidy. The initiative is also expected to serve as a case study, providing a replicable model for other vulnerable cities on how to secure essential infrastructure and protect populations from escalating climate threats.
The Post-Paris Agreement Era: Growing Complexity
The decade since the landmark 2015 Paris Agreement and UN Sustainable Development Goals (SDGs) has seen the global sustainability agenda become dramatically more complex. While foundational progress was made—with solar energy costs falling over 85% and ESG assets growing into the trillions—the focus has expanded far beyond carbon emissions. The agenda now encompasses a daunting array of interconnected challenges, from the 2022 global biodiversity framework aiming to protect 30% of the planet to the geopolitical scramble for critical minerals. It also must address the increasingly difficult management of water resources, the growing energy demands of AI, a surge of e-waste, and the imperative of a just transition for workers. This diversification—spanning nature, equity, technology, and infrastructure—creates a profound new challenge for the public and investors alike, who must now track success not by a single metric, but by the progress of a dozen intertwined planetary and social systems.
The sheer scope of these challenges makes it impossible for any single investor, including an experienced firm like Meridiam, to address them all. Despite this, the company continues to expand its focus, the CEO of the company says: "We are constantly moving further forward the frontier of what can be done to support communities worldwide for a better current quality of life in the present and for future generations."
This strategy is evident in recent moves, such as Meridiam's investment in Suez, a global leader in water and waste management. Suez operates essential water and sanitation infrastructure under long-term public contracts. Following its acquisition, Meridiam and other shareholders established a new governance framework for Suez, including a Sustainable Development Roadmap and dedicated oversight committees, to enforce greater corporate accountability and embed ESG principles directly into its main business operations.
This investment is designed to deliver impact at scale, positively affecting the 57 million people who rely on Suez for drinking water. It also adds to a robust portfolio of 75 projects, each structured to generate competitive financial returns alongside measurable community benefits. While these projects span different sectors and continents, they are unified by a consistent investment philosophy that prioritizes long-term, patient capital. This approach targets a convergence of global trends—climate change, rapid urbanization, and the need for inclusive development—positioning it not merely as a niche strategy, but as a new vital model for building a more resilient and equitable future.
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