The Greater Paris Metropolis was created on January 1st 2016 by the Law of 27 January 2014 on the Modernisation of Territorial Public Action and the Affirmation of Metropolitan Areas (Maptam Law), completed by the Law of 7 August 2015 on the New Territorial Organisation of the Republic (NOTRe Law).

Greater Paris Metropolis is an intermunicipal authority composed of 130 municipalities. It includes Paris, the 122 municipalities in the three departments of Hauts-de-Seine, Seine-Saint-Denis and Val-de-Marne, and seven municipalities in the neighbouring departments of Essonne and Val-d’Oise, representing nearly 7.2 million residents in total.

Working to restore balance between territories and improve living environments for metropolitan residents.

As a public body of intermunicipal cooperation with its own taxation revenue and specific status, the Greater Paris Metropolis exercises powers in five mandatory areas, as defined in the metropolitan program:

• Economic, social and cultural development and planning;
• Environmental protection and enhancement and living environment policy;
• Development of the metropolitan space;
• Local housing policy;
• Management of aquatic environments and flood prevention.

The flood risk that threatens the safety of people, property, infrastructure, economic activity, and the environment is a major concern for La Métropole du Grand Paris, which remains highly vulnerable. If a major flood similar to that of 1910 were to occur again, it would leave 5 million metropolitan residents without drinking water and cause 30 billion euros in damages. La Métropole du Grand Paris, together with Seine Grands Lacs (Public Territorial Basin Establishment (EPTB)), is implementing an ambitious strategy to reduce flood-related risks.

With Seine Grands Lacs, la Métropole du Grand Paris commits to a reciprocal solidarity: a solidarity from downstream to upstream, complementing the existing upstream-to-downstream solidarity. Thanks to this joint action and the proceeds from the GeMAPI tax, works (Flood Expansion Zones) are funded over more than 250 km of La Métropole du Grand Paris, and innovative measures are developed to combat the effects of flooding. These are in addition to compensations for farmers in the context of over-flooding under the agreements signed with the Chambers of Agriculture.