Block modulus coding (BMC) systems implement block coding on non-binary modulus m symbols, where m is greater than 2. BMC systems can be used for, among other things, forward error correction (FEC) of source data in communication systems or parity backup for error correction of source data in storage systems where the source data is represented by non-binary symbols that may be corrupted by burst errors. The block coding is preferably performed using a distributed arrangement of block encoders or decoders. A distributed block modulus encoder (DBME) encodes sequential source data symbols of modulus m with a plurality of sequential block encoders to produce interleaved parity codewords. The codewords utilize modulus m symbols where the medium can reliably resolve m symbol states. The interleaved parity codewords enable decoding of error-corrected source data symbols of modulus m with a distributed block modulus decoder (DBMD).