diff --git a/src/riverroute/mosart_tspatialunit_type.F90 b/src/riverroute/mosart_tspatialunit_type.F90
index cb4f6e4..80449b7 100644
--- a/src/riverroute/mosart_tspatialunit_type.F90
+++ b/src/riverroute/mosart_tspatialunit_type.F90
@@ -360,11 +360,13 @@ subroutine Init(this, begr, endr, ntracers, nt_ice, nlon, nlat, EMesh, &
             if (this%twidth(n) < 0._r8) then
                this%twidth(n) = 0._r8
             end if
+            if ( this%tlen(n) > 0._r8) then
             if ( this%tlen(n) > 0._r8 .and. &
                  (this%rlenTotal(n)-this%rlen(n))/this%tlen(n) > 1._r8 ) then
                this%twidth(n) = c_twid(n)*this%twidth(n) * &
                     ((this%rlenTotal(n)-this%rlen(n))/this%tlen(n))
             end if
+            endif
             if (this%tlen(n) > 0._r8 .and. this%twidth(n) <= 0._r8) then
                this%twidth(n) = 0._r8
             end if