1. A method comprises: determining access performance to copies of dispersed storage encoded data, wherein the copies of the dispersed storage encoded data are stored in a set of a plurality of dispersed storage networks (DSNs); when the access performance is not at a desired access performance level, modifying the set of the plurality of DSNs based on the access performance and the desired access performance level to produce a modified set of the plurality of DSNs; and for a new DSN of the modified set of the plurality of DSNs: determining error coding dispersal storage parameters based on local data retrieval accesses allocated to the new DSN; and facilitating the new DSN storing another copy of the dispersed storage encoded data.