diff --git a/interface/framework/assimilate_pdaf.F90 b/interface/framework/assimilate_pdaf.F90
index 3afcd201..4784b07d 100644
--- a/interface/framework/assimilate_pdaf.F90
+++ b/interface/framework/assimilate_pdaf.F90
@@ -46,12 +46,14 @@ SUBROUTINE assimilate_pdaf()
   USE mod_assimilation, &      ! Variables for assimilation
        ONLY: filtertype
   USE mod_assimilation, ONLY: use_omi
+#ifdef CLMSA
 #ifdef CLMFIVE
   USE PDAF_interfaces_module, &   ! Check consistency of PDAF calls
       ONLY: PDAFomi_assimilate_local, PDAFomi_assimilate_global, &
       PDAFomi_assimilate_lenkf, PDAF_get_localfilter, &
       PDAFomi_assimilate_enkf_nondiagR, &
       PDAFomi_assimilate_global_nondiagR, PDAFomi_assimilate_local_nondiagR
+#endif
 #endif
 
   IMPLICIT NONE
@@ -134,6 +136,7 @@ SUBROUTINE assimilate_pdaf()
 ! *********************************
 
   OMI: IF (use_omi) THEN
+#ifdef CLMSA
 #ifdef CLMFIVE
     CALL PDAF_get_localfilter(localfilter)
 
@@ -167,6 +170,7 @@ SUBROUTINE assimilate_pdaf()
       END IF
 
     END IF
+#endif
 #endif
   ELSE OMI
 
diff --git a/interface/framework/callback_obs_pdafomi.F90 b/interface/framework/callback_obs_pdafomi.F90
index c34031d3..05cfa953 100644
--- a/interface/framework/callback_obs_pdafomi.F90
+++ b/interface/framework/callback_obs_pdafomi.F90
@@ -32,6 +32,7 @@
 
 ! Author: Yorck Ewerdwalbesloh
 
+#ifdef CLMSA
 #ifdef CLMFIVE
   SUBROUTINE init_dim_obs_pdafomi(step, dim_obs)
 
@@ -365,3 +366,4 @@ SUBROUTINE deallocate_obs_pdafomi()
   END SUBROUTINE deallocate_obs_pdafomi
 
 #endif
+#endif
diff --git a/interface/framework/init_pdaf_parse.F90 b/interface/framework/init_pdaf_parse.F90
index 9a3356c3..09025113 100644
--- a/interface/framework/init_pdaf_parse.F90
+++ b/interface/framework/init_pdaf_parse.F90
@@ -59,12 +59,10 @@ SUBROUTINE init_pdaf_parse()
   use mod_assimilation,&
        only: cradius_GRACE, sradius_GRACE, &
        cradius_SM, sradius_SM
+#ifdef CLMSA
 #ifdef CLMFIVE
   use obs_GRACE_pdafomi, only: rms_obs_GRACE
   use obs_SM_pdafomi, only: rms_obs_SM
-#endif
-#if defined CLMSA
-#ifdef CLMFIVE
   use enkf_clm_mod, only: use_omi_model
 #endif
 #endif
@@ -99,6 +97,7 @@ SUBROUTINE init_pdaf_parse()
   handle = "rms_obs"                 ! Assumed uniform RMS error of the observations
   CALL parse(handle, rms_obs)
 
+#ifdef CLMSA
 #ifdef CLMFIVE
   rms_obs_GRACE = rms_obs  ! backward compatibility
   handle = "rms_obs_GRACE"          ! RMS error for GRACE observations
@@ -109,6 +108,7 @@ SUBROUTINE init_pdaf_parse()
   ! rms_obs_C = rms_obs              ! backward compatibility
   ! handle = 'rms_obs_C'             ! RMS error for C observations
   ! CALL parse(handle, rms_obs_C)
+#endif
 #endif
 
   handle = "dim_obs"                 ! Number of observations
diff --git a/interface/framework/mod_read_obs.F90 b/interface/framework/mod_read_obs.F90
index 51d2c59b..af734d79 100755
--- a/interface/framework/mod_read_obs.F90
+++ b/interface/framework/mod_read_obs.F90
@@ -837,6 +837,7 @@ subroutine check(status)
   end subroutine check
 
 
+#ifdef CLMSA
 #ifdef CLMFIVE
     !> @author Anne Springer, adaptation for TSMP2 by Yorck Ewerdwalbesloh
     !> @date 04.12.2023
@@ -888,7 +889,6 @@ subroutine check_n_observationfile_set_zero(fn,nn)
         end if
 
     end subroutine check_n_observationfile_set_zero
-#endif
 
     !> @author Yorck Ewerdwalbesloh
     !> @date 29.10.2025
@@ -947,7 +947,6 @@ subroutine check_n_observationfile_next_type(fn, obs_type_str)
     end subroutine check_n_observationfile_next_type
 
 
-#ifdef CLMFIVE
     !> @author Yorck Ewerdwalbesloh
     !> @date 29.10.2025
     !> @brief Update observation type for next assimilation cycle
@@ -1188,6 +1187,7 @@ subroutine domain_def_clm(lon_clmobs, lat_clmobs, dim_obs, &
 
     end subroutine domain_def_clm
 #endif
+#endif
 
 
 end module mod_read_obs
diff --git a/interface/framework/next_observation_pdaf.F90 b/interface/framework/next_observation_pdaf.F90
index 7f246c4d..ba4c043a 100644
--- a/interface/framework/next_observation_pdaf.F90
+++ b/interface/framework/next_observation_pdaf.F90
@@ -65,6 +65,7 @@ SUBROUTINE next_observation_pdaf(stepnow, nsteps, doexit, time)
   USE mod_assimilation, ONLY: use_omi
   use mod_read_obs, &
        only: check_n_observationfile, check_n_observationfile_da_interval
+#ifdef CLMSA
 #ifdef CLMFIVE
   use mod_read_obs, only: check_n_observationfile_set_zero
   use mod_read_obs, only: check_n_observationfile_next_type
@@ -73,6 +74,7 @@ SUBROUTINE next_observation_pdaf(stepnow, nsteps, doexit, time)
   use clm_varcon, only: set_averaging_to_zero
   use clm_varcon, only: ispval
   use enkf_clm_mod, only: clmupdate_tws
+#endif
 #endif
   IMPLICIT NONE
 
diff --git a/interface/framework/obs_GRACE_pdafomi.F90 b/interface/framework/obs_GRACE_pdafomi.F90
index 657c7def..47dc8e1d 100644
--- a/interface/framework/obs_GRACE_pdafomi.F90
+++ b/interface/framework/obs_GRACE_pdafomi.F90
@@ -50,6 +50,7 @@
 !! * 2019-06 - Lars Nerger - Initial code
 !! * Later revisions - see repository log
 !!
+#ifdef CLMSA
 #ifdef CLMFIVE
 MODULE obs_GRACE_pdafomi
 
@@ -1420,6 +1421,7 @@ end subroutine deallocate_obs_GRACE
 
   END MODULE obs_GRACE_pdafomi
 #endif
+#endif
 
 
 
diff --git a/interface/framework/obs_SM_pdafomi.F90 b/interface/framework/obs_SM_pdafomi.F90
index e6c10b81..4a5d1439 100644
--- a/interface/framework/obs_SM_pdafomi.F90
+++ b/interface/framework/obs_SM_pdafomi.F90
@@ -54,6 +54,7 @@
 ! Author: Yorck Ewerdwalbesloh, adaptations of original implementations of TSMP2-PDAF interface for OMI framework
 
 
+#ifdef CLMSA
 #ifdef CLMFIVE
 MODULE obs_SM_pdafomi
 
@@ -1403,3 +1404,4 @@ end subroutine deallocate_obs_SM
 
   END MODULE obs_SM_pdafomi
 #endif
+#endif
diff --git a/interface/framework/prepoststep_ens_pdaf.F90 b/interface/framework/prepoststep_ens_pdaf.F90
index 0c8b97ba..7814b31b 100644
--- a/interface/framework/prepoststep_ens_pdaf.F90
+++ b/interface/framework/prepoststep_ens_pdaf.F90
@@ -75,14 +75,18 @@ SUBROUTINE prepoststep_ens_pdaf(step, dim_p, dim_ens, dim_ens_p, dim_obs_p, &
     use mod_tsmp, &
         only: tag_model_parflow, pf_statevecsize, nprocclm, model
 
+#ifdef CLMSA
 #ifdef CLMFIVE
     USE mod_assimilation, ONLY: use_omi
+#endif
 #endif
 
     IMPLICIT NONE
 
+#ifdef CLMSA
 #ifdef CLMFIVE
     external :: deallocate_obs_pdafomi
+#endif
 #endif
 
     ! !ARGUMENTS:
@@ -275,6 +279,7 @@ SUBROUTINE prepoststep_ens_pdaf(step, dim_p, dim_ens, dim_ens_p, dim_obs_p, &
     firsttime = .FALSE.
     end if
 
+#ifdef CLMSA
 #ifdef CLMFIVE
     OMI: IF (use_omi) THEN ! deallocate observation arrays for second call of prepoststep
         if (firsttime_omi) then
@@ -285,4 +290,5 @@ SUBROUTINE prepoststep_ens_pdaf(step, dim_p, dim_ens, dim_ens_p, dim_obs_p, &
         end if
     end if OMI
 #endif
+#endif
 END SUBROUTINE prepoststep_ens_pdaf
diff --git a/interface/model/eclm/enkf_clm_5.F90 b/interface/model/eclm/enkf_clm_5.F90
index b383c28b..7ab90f15 100644
--- a/interface/model/eclm/enkf_clm_5.F90
+++ b/interface/model/eclm/enkf_clm_5.F90
@@ -68,8 +68,8 @@ subroutine clm_init(finname, pdaf_id, pdaf_max, mype) bind(C,name="clm_init")
 !!<< TSMP PDAF comment out end
 !!>> TSMP PDAF addition beginning
   use, intrinsic :: iso_C_binding, only: c_char, c_int
-  use enkf_clm_mod, only: COMM_model_clm
 #if defined CLMSA
+  use enkf_clm_mod, only: COMM_model_clm
   use enkf_clm_mod, only: define_clm_statevec
 #endif
   use clm_varcon, only: averaging_var
@@ -108,10 +108,18 @@ subroutine clm_init(finname, pdaf_id, pdaf_max, mype) bind(C,name="clm_init")
 !!>> TSMP PDAF comment out beginning
   ! call cime_pre_init1(esmf_logfile_option)
 !!>> TSMP PDAF addition beginning
+#if defined CLMSA
   call cime_pre_init1(esmf_logfile_option, &
                       COMM_model_clm, &
                       pdaf_id=pdaf_id, &
                       pdaf_max=pdaf_max)
+#endif
+
+#if defined COUP_OAS_PFL
+  ! EXPERIMENTAL: For eCLM-ParFlow-PDAF, the whole management of
+  ! communicators has to be re-traced, see HPSCTerrSys/pdaf#82
+  call cime_pre_init1(esmf_logfile_option)
+#endif
 !!<< TSMP PDAF addition end
 
   end_count = shr_sys_irtc(irtc_rate)
@@ -203,10 +211,12 @@ end subroutine clm_init
 !--------------------------------------------------------------------------
 subroutine clm_advance(ntstep, tstartcycle, mype) bind(C,name="clm_advance")
   use cime_comp_mod, only : cime_run
+#if defined CLMSA
   use enkf_clm_mod, only : cleanup_clm_statevec
   use enkf_clm_mod, only : define_clm_statevec
   use enkf_clm_mod, only : set_clm_statevec
   use enkf_clm_mod, only : use_omi_model
+#endif
   use, intrinsic :: iso_C_binding, only : c_int
 
   implicit none
@@ -242,7 +252,9 @@ subroutine clm_finalize() bind(C,name="clm_finalize")
 
   ! use ESMF,          only : ESMF_Initialize, ESMF_Finalize
   use cime_comp_mod, only : cime_final
+#if defined CLMSA
   use enkf_clm_mod, only : cleanup_clm_statevec
+#endif
 
   implicit none