diff --git a/src/encounter/encounter_io.f90 b/src/encounter/encounter_io.f90
index 1333c05aa..50180113c 100644
--- a/src/encounter/encounter_io.f90
+++ b/src/encounter/encounter_io.f90
@@ -232,7 +232,7 @@ module subroutine encounter_io_netcdf_write_frame_snapshot(self, history, param)
  
       ! Internals
       integer(I4B)           :: i, idslot, old_mode, npl, ntp
-      character(len=:), allocatable :: charstring
+      character(len=STRMAX) :: charstring
 
       select type(param)
       class is (swiftest_parameters)