Multiformalism modeling allows different formal modeling languages to be used for different subsystems based on their complexity and abstraction level. This provides advantages over simulation-only approaches by enabling quantitative dependability metrics to be analytically evaluated and properties to be verified. The objectives of this work are to explore using multiformalism modeling for critical infrastructures and propose a general scheme for intra- and inter-infrastructure models. Future work includes completing a case study application and analyzing composition operators and model-checking of multi-formalism models.