the Syndicat mixte pour l'assainissement et la gestion des eaux du bassin versant de l'yerres (Syage) operates at two levels in the watershed:- on the downstream part, it ensures, as project owner, the maintenance and development of the river and its tributaries, the management of the sanitation and rainwater network.- On the whole of the Bv, it implements the Sage de l'yerres since its approval in 2011 and the Papi labeled in March 2018.The Syage therefore needs to regularly acquire topographic data, most of the time at 1/200th or 1/500th, whether in the field of sanitation or river management as well as land services
topographic services, cartographic services in sanitation (wastewater), and management of rainwater and aquatic environments and flood prevention in 8 municipalities (Group 1)places of execution: Santeny, Villeneuve-Saint-Georges, Villecresnes, Mandres-Les-Roses, Périgny, Marolles-En-Brie, Villeneuve-Le-Roi, Valenton
topographic services, cartographic services in sanitation (wastewater) and management of rainwater and aquatic environments and flood prevention (Gemapi) in 10 municipalities (Group 2)places of execution: épinay-sous-sénart, Vigneux-sur-Seine, Boussy-Saint-Antoine, Varennes-Jarcy, Montgeron, Yerres, Brunoy, Crosne, Draveil, Quincy-sous-Sénart
topographic and cartographic services in water and aquatic environment management and flood prevention (Gemapi) in 58 municipalities (Group 3)places of execution: Jouy-Le-Châtel, Courtomer, Boisdon, Aubepierre-Ozouer-Le-Repos, Crisenoy, Touquin, La Chapelle-Iger, Champeaux, Nangis, Hautefeuille, Gastins, Beautheil-Saints, Verneuil-L'Étang, Châteaubleau, Courpalay, Clos-Fontaine, Amillis, Dagny, Rozay-En-Brie, Vieux-Champagne, Andrezel, Maison-Rouge, Tigery, Courchamp, La Chapelle-Saint-Sulpice, Le Plessis-Feu-Aussoux, Vanvillé, Chaumes-En-Brie, Quiers, Chenoise-Cucharmoy, Faremoutiers, Rampillon, Moissy-Cramayel, Beauvoir, Soignolles-En-Brie, Grandpuits-Bailly-Carrois, Bannost-Villegagnon, Yèbles, Pécy, Limoges-Fourches, Vaudoy-En-Brie, Voinsles, Bernay-Vilbert, Pézarches, Combs-La-Ville, Champcenest, Sognolles-En-Montois, Guignes, La Celle-Sur-Morin, Saint-Hilliers, Saint-Ouen-En-Brie, Saint-Just-En-Brie, Mormant, La Croix-En-Brie, évry-grégy-sur-yerre, Bezalles, Lissy, Argentières
topographic and cartographic services in water and aquatic environment management and flood prevention (Gemapi) in 40 municipalities (Group 4)places of execution: Jossigny, La Queue-En-Brie, Marles-En-Brie, Limeil-Brévannes, Servon, Brie-Comte-Robert, Lumigny-Nesles-Ormeaux, Grisy-Suisnes, Férolles-Attilly, Sucy-En-Brie, Ozoir-la-Ferrière, Gretz-Armainvilliers, Châtres, Ozouer-le-Voulgis, Lésigny, Liverdy-en-Brie, La Houssaye-en-Brie, Voulangis, Presles-en-Brie, Favières, Crèvecoeur-en-Brie, Solers, Serris, Courquetaine, Coubert, Pontcarré, Villeneuve-le-Comte, Les Chapelles-Bourbon, Villiers-sur-Morin, Boissy-Saint-Léger, Chevry-Cossigny, Fontenay-Trésigny, Tournan-En-Brie, Mortcerf, Bussy-Saint-Georges, Coutevroult, Neufmoutiers-En-Brie, Villeneuve-Saint-Denis, Bailly-Romainvilliers, Guérard
land services throughout the territory of Syage (Group 5)Places of execution: throughout the Yerres watershed