diff --git a/script/classif_bassins.r b/script/classif_bassins.r
new file mode 100644
index 0000000000000000000000000000000000000000..68df3ceec545c3c944e6dfd6f1176d43f03506db
--- /dev/null
+++ b/script/classif_bassins.r
@@ -0,0 +1,72 @@
+# loading libraries
+library(sf)
+library(geau)
+
+# loading dataset
+bassin = sf::st_read("/home/dnm/Seafile/data-common/data/topage/bassin_versant/2019/06_RhУne-MВditerranВe_BassinVersantTopographique.shp")
+
+# checking and adjusting crs (if needed)
+if (!sf::st_crs(bassin) == sf::st_crs(geau::so_ii_limit)) {
+    bassin = sf::st_transform(bassin, crs = sf::st_crs(geau::so_ii_limit))
+}
+
+if (!sf::st_crs(subsector) == sf::st_crs(geau::so_ii_limit)) {
+    subsector = sf::st_transform(subsector, crs = sf::st_crs(geau::so_ii_limit))
+}
+
+# data manipulation
+selection_col = c("CdOH", "TopoOH", "geometry")
+selection_row = list(
+    mosson = c(
+        '06B0000002150456066',
+        '06B0000002150458403',
+        '06B0000002150458401',
+        '06B0000002150456007',
+        '06B0000002150455994'
+        ),
+    lez = c(
+        '06B0000002150456086',
+        '06B0000002150456009'
+        ),
+    lor = c(
+        '06B0000002150456068',
+        '06B0000002150456055',
+        '06B0000002150456053',
+        '06B0000002150461370',
+        '06B0000002150457044'
+    )
+)
+
+bassin_so_ii = bassin[bassin[["CdOH"]] %in% unlist(unname(selection_row)), selection_col]
+names(bassin_so_ii) = c("id", "bassin", "geometry")
+bassin_so_ii[["degre"]] = 2
+
+bassin_mosson_geom = bassin[bassin[["CdOH"]] %in% unlist(unname(selection_row[["mosson"]])), selection_col] |> sf::st_union()
+bassin_mosson_df = data.frame(
+    id = "soii01",
+    bassin = "Bassin Mosson",
+    degre = 1
+)
+bassin_mosson = sf::st_set_geometry(bassin_mosson_df, bassin_mosson_geom)
+
+bassin_lez_geom = bassin[bassin[["CdOH"]] %in% unlist(unname(selection_row[["lez"]])), selection_col] |> sf::st_union()
+bassin_lez_df = data.frame(
+    id = "soii02",
+    bassin = "Bassin Lez",
+    degre = 1
+)
+bassin_lez = sf::st_set_geometry(bassin_lez_df, bassin_lez_geom)
+
+bassin_lor_geom = bassin[bassin[["CdOH"]] %in% unlist(unname(selection_row[["lor"]])), selection_col] |> sf::st_union()
+bassin_lor_df = data.frame(
+    id = "soii03",
+    bassin = "Bassin L'or",
+    degre = 1
+)
+bassin_lor = sf::st_set_geometry(bassin_lor_df, bassin_lor_geom)
+
+bassin_so_ii = rbind(bassin_so_ii, bassin_mosson)
+bassin_so_ii = rbind(bassin_so_ii, bassin_lez)
+bassin_so_ii = rbind(bassin_so_ii, bassin_lor)
+
+sf::st_write(bassin_so_ii, dsn = "data-common/so-ii/topage/2021-09/bassin_versant_so_ii.shp")