diff --git a/layers/transportation_name/network_type.sql b/layers/transportation_name/network_type.sql
new file mode 100644
index 00000000..9d074ff6
--- /dev/null
+++ b/layers/transportation_name/network_type.sql
@@ -0,0 +1,40 @@
+DO $$
+    BEGIN
+        BEGIN
+            ALTER TABLE osm_route_member ADD COLUMN network_type text;
+        EXCEPTION
+            WHEN duplicate_column THEN RAISE NOTICE 'column omt_type already exists in network_type.';
+        END;
+    END;
+$$
+;
+
+-- see http://wiki.openstreetmap.org/wiki/Relation:route#Road_routes
+UPDATE osm_route_member
+SET network_type =
+    CASE
+      WHEN network = 'US:I' THEN 'us-interstate'
+      WHEN network = 'US:US' THEN 'us-highway'
+      WHEN network LIKE 'US:__' THEN 'us-state'
+      ELSE ''
+    END
+;
+
+
+DO $$
+BEGIN
+    IF NOT EXISTS (SELECT 1 FROM pg_type WHERE typname = 'route_network_type') THEN
+        CREATE TYPE route_network_type AS ENUM ('us-interstate', 'us-highway', 'us-state', '');
+    END IF;
+END
+$$
+;
+
+ALTER TABLE osm_route_member ALTER COLUMN network_type TYPE route_network_type USING network_type::route_network_type;
+
+-- select network_type, count(*)
+-- from osm_route_member
+-- WHERE network_type <> ''
+-- group by network_type
+-- order by network_type
+-- ;
diff --git a/layers/transportation_name/transportation_name.yaml b/layers/transportation_name/transportation_name.yaml
index 7cb91e4b..f01f6283 100644
--- a/layers/transportation_name/transportation_name.yaml
+++ b/layers/transportation_name/transportation_name.yaml
@@ -34,6 +34,7 @@ layer:
     srid: 900913
     query: (SELECT geometry, name, name_en, ref, ref_length, class::text FROM layer_transportation_name(!bbox!, z(!scale_denominator!))) AS t
 schema:
+  - ./network_type.sql
   - ./merge_highways.sql
   - ./layer.sql
 datasources: