Syndicat Mixte d’aménagement, de gestion et d’entretien des berges de la Seine et de l’Oise (SMSO)

SMSO is a group of public authorities set up in 2005 to develop, manage and maintain the banks of the Seine and the Oise. Two ideas prompted its creation: the département was keen to map out a future for the Seine as a major development focus, and the municipalities were keen to make the Seine a part of citizens’ everyday life and the region’s economic development. All of the municipalities in the Yvelines situated along the Seine are members of SMSO (except Epône and Issou). Since its inception, it has undertaken 14 operations (completed or in progress) and is currently conducting 13 studies, concerning around 20 municipalities over a linear distance of 13km.

Budget and funding

Funding arrangements: most of SMSO’s funding consists of contributions from the regional authorities and grants.

Roles and responsibilities

Develop and restore the river banks: reinforce the banks to prevent erosion and reinstate fauna and flora in the areas suitable for installing and developing typical river-environment fauna and flora

  • Prevent river bank erosion = restore and stabilise the banks in Triel-sur-Seine in 2011
  • Restore the banks and reinstate fauna and flora to allow biodiversity to return and develop = Andrésy in 2011 (over a linear distance of 250m)
  • Restore and extend embankments = Sartrouville, Montesson
  • Let the public experience the wealth and variety of the wildlife, the heritage and the landscape and provide areas in which people can rest and think = build a panoramic viewpoint in Medan in 2011

Maintain the river banks: foster ecological diversification, essentially in river environments

  • 200km of river banks to be maintained: since end-2009, 18km have actually been maintained (in 34 municipalities)
  • Maintenance carried out from a barge on the river and on land, sanitation cutting and enhancement cutting, clearing, path management, etc.

Provide for soft modes of transport and river crossings: facilitate and enhance the public’s experience of the natural heritage and landscape, essentially focused on the water

  • Build 3 footbridges, beginning in 2013; river ferry between Moisson (Yvelines) and Vétheuil (Val d’Oise)
  • Seine en Selle (mountain bike and hybrid bike ride on the paths opened up along the Seine) since 2010; cruises on the Seine organised jointly with the Conseil général

Partnership goals

On 3 February 2012, the Conseil général des Yvelines adopted the Yvelines Seine plan, which aims to accelerate development of the strategic area formed by the Seine valley and, in a broader perspective, make the département more attractive. SMSO is a key tool for carrying out this plan. A meeting held on 13 July 2012 reviewed SMSO’s actions since its inception and defined three objectives for the département: enhance the Seine river bank landscape to make it more attractive for people living in the Yvelines; as far as possible, ensure that pedestrian and cycle paths along the Seine are unbroken; and encourage soft means of crossing the river, mainly by establishing ferry services. With these goals in mind, an agreement was drawn up on 15 February 2013.

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