Hello,
ZF is generally read in the geometry file (under the name BOTTOM or FOND with unit in M) or you can build it in subroutine CORFON. H, U and V are initialised in subroutine CONDIN (depending on keyword INITIAL CONDITIONS, but you can implement it also). For the Strickler coefficients you can build them in subroutine STRCHE (library bief), and if they are defined with zones refer to the documentation and you have an example in case DONAU.
Regards,
JMH