diff --git a/pyproject.toml b/pyproject.toml
index 52d3ff7..369dd57 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -34,6 +34,7 @@ dependencies = [
     "pandas>=2.3",
     "geopandas>=1.1",
     "shapely>=2.0",
+    "pyproj>=3.6",
 
     # Visualization
     "dash>=3.3",