diff --git a/opm/core/pressure/tpfa/ifs_tpfa.c b/opm/core/pressure/tpfa/ifs_tpfa.c
index 56bcb995..a1a564df 100644
--- a/opm/core/pressure/tpfa/ifs_tpfa.c
+++ b/opm/core/pressure/tpfa/ifs_tpfa.c
@@ -153,7 +153,7 @@ compute_grav_term(struct UnstructuredGrid *G, const double *gpress,
 /* ---------------------------------------------------------------------- */
 static int
 assemble_bc_contrib(struct UnstructuredGrid       *G    ,
-                    struct FlowBoundaryConditions *bc   ,
+                    const struct FlowBoundaryConditions *bc   ,
                     const double                  *trans,
                     struct ifs_tpfa_data          *h    )
 /* ---------------------------------------------------------------------- */
diff --git a/opm/core/pressure/tpfa/ifs_tpfa.h b/opm/core/pressure/tpfa/ifs_tpfa.h
index ece4a6be..4f0c2938 100644
--- a/opm/core/pressure/tpfa/ifs_tpfa.h
+++ b/opm/core/pressure/tpfa/ifs_tpfa.h
@@ -41,7 +41,7 @@ struct ifs_tpfa_data {
 
 struct ifs_tpfa_forces {
     const double *src;
-    struct FlowBoundaryConditions *bc;
+    const struct FlowBoundaryConditions *bc;
 };