Yolo Bypass is an ecological feature of the Bay-Delta ecosystem in California that provides floodplain habitat for spawning and rearing of Sacramento Splittail (Pogonichthys macrolepidotus) and rearing of juvenile Chinook Salmon (Oncorhynchus tshawytscha) when inundated. We used outputs from 10 climate change models for two Representative Concentration Pathways (RCPs) for greenhouse gas concentrations to assess the effects of climate change on the frequency, duration, and timing of flood flows in Yolo Bypass. We also assessed a planned notched weir modification to the primary weir that controls inflow from the Sacramento River into Yolo Bypass that has been designed to allow the bypass to be inundated at lower river flows.