The U.S. state of Florida is estimated to have 1.2 million alligators. And 200,000 of these – one in six – live in the Everglades. A unique ecosystem, it is often described as the lungs of the southern United States even though it has been suffering from water pollution for decades.

The pollution, which includes poisonous algae, threatens the lucrative tourism industry on both sides of the peninsula: the Gulf as well as the Atlantic. That is why the state is investing $2.3 billion and the federal government another $1 billion to restore the environment and the quality of its waters as part of the Comprehensive Everglades Restoration Plan. Of all the projects that come under this plan, the C-43 is the most important.

Under development by Webuild, it aims to reduce harmful discharges from residential and agricultural developments.

The project includes the construction of an earth-fill dam with a perimetre of approximately 26.2 kilometres and a separator dam 4.5 kilometres long. The resulting reservoir will encompass 40.5 square kilometres and store nearly 210 million cubic metres. When it rains, the reservoir will capture contaminated water run-offs. When the rains pass, it will maintain a minimum flow of fresh water to the estuary so as to reduce extreme salinity changes.