diff --git a/Project.toml b/Project.toml
index 2c5920d2..5506c0b6 100644
--- a/Project.toml
+++ b/Project.toml
@@ -40,6 +40,7 @@ CellArrays = "0.2"
 GeoParams = "0.5, 0.6"
 HDF5 = "0.17.1"
 ImplicitGlobalGrid = "0.15"
+Interpolations = "0.15"
 JLD2 = "0.4, 0.5"
 JustPIC = "0.5"
 MPI = "0.20"