anchor.diff:  module local_routines 
       use global_mod, only: dp, ip, wall_elevation
  -    use domain_mod, only: domain_type
  +    use domain_mod, only: domain_type, STG, UH, VH, ELV
       implicit none
   
       contains 
  
positive.code:         !domain%U(:,domain%nx(2),4) = 20.0_dp !wall_elevation
  
          ! Ensure stage >= elevation
          domain%U(:,:,1 ) = max(domain%U(:,:,1), domain%U(:,:,4))
  
      
          domain%manning_squared = 0.0_dp
  
negative.code:         initial_stage_2 = h_upstream !1.0_dp
  
          ! Stage
          domain%U(:,:,STG) = initial_stage_1 
          domain%MSL_linear = initial_stage_1
          do j = 1, domain%nx(2)
              where(domain%x > 0.0_dp) domain%U(:,j,STG) = initial_stage_2
          end do
  
          ! Elevation
          domain%U(:,:,ELV) = 0._dp
          !! Wall boundaries (without boundary conditions)
          !domain%U(1,:,4) = 20.0_dp !wall_elevation 
          !domain%U(domain%nx(1),:,4) = 20.0_dp !wall_elevation 
  