diff --git a/pyproject.toml b/pyproject.toml
index 31c3daa1..68be99f4 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -47,8 +47,8 @@ dependencies = [
 	"erddapy>=2.0.2",
 	#copernicusmarine>=2.0.0 has breaking changes compared to v1
 	"copernicusmarine>=2.0.0",
-	#rws-ddlpy>=0.8.0 connects to new RWS waterwebservices/ddapi20
-	"rws-ddlpy>=0.8.0",
+	#rws-ddlpy>=0.9.3 added caching for ddlpy.locations() including dependency
+	"rws-ddlpy>=0.9.3",
 	#pooch>=1.1.0 has attribute retrieve
 	"pooch>=1.1.0",
 	#hydrolib-core>=0.9.9 removed obsolete keywords to avoid model crash with 2026.01