These data include pumping, injection, and water spreading input data for the MODFLOW-6 extension and update to Los Angeles Coastal Plain Groundwater Model (LACPGM-MF6) for the years 2016-2020. The LACPGM-MF6 required model inputs to represent groundwater injection, groundwater extraction, and water spreading. Extended datasets include four barrier project injection rates, two groundwater production extraction rates, and one water spreading infiltration rates. The data were made available by the two local water agencies, Water Resources Division of Los Angeles and the Orange County Water District. Spreading data were formatted for the MODFLOW-6 well package and both injection and extraction data were formatted for the MODFLOW-6 multi-aquifer well package.