Despite the growing scientific evidence, the electricity market models used in Chile do not consider the effects of climate change on hydroelectric energy production. Based on a statistical analysis of the historical hydro-energy inflow dataset and a revision of the scientific literature, we suggest a set of technical and statistical criteria to determine an alternative representation of the hydro-energy uncertainty in the Chilean electricity market. Based on these criteria, we then propose an alternative range of historical hydrological data, which is built by shedding the first 35 years of the historical dataset (out of 59 years) and using only a reduced subset of 24 years. Additionally, we propose to capture the potential impacts of even more prolonged droughts on the Chilean electricity system by repeating the last nine years of data at the end of the 24 year-long series. The resulting extended subset of 33 hydro-years is approximately 10% drier on average than the original dataset of 59 years. The proposed range of hydrological data captures some of the anticipated effects of climate change on Chilean hydro-uncertainty reported in the literature and also preserves most of the intra-annual and spatial diversity of the original data.