This dataset, collected by CARRTEL-INRAE in collaboration with the municipality of Tignes, is part of a study on climate change impacts on the thermal structure and water quality of Lake Tignes. Monthly physico-chemical measurements (temperature, conductivity, pH, salinity, oxygen concentration, and oxygen saturation) were conducted from May 2022 to March 2023 at the deepest points of the lake's two basins using a KorEXO multi-parameter probe. Additional high-frequency data on temperature, oxygen, and light were gathered at various depths near the outlet sub-basin from May 2022 to September 2023. Laboratory analyses focused on the chemical composition of the water in the euphotic and deeper layers (e.g., nutrients, ions, chlorophylls, and pigments) following standardized protocols. Phytoplankton community counts were also conducted. Lake tributary parameters were measured with a multiparameter probe. Detailed methodology and data descriptions are available in the scientific report: Prospective et effets du changement climatique sur le lac de Tignes (CARRTEL, 2024, ⟨hal-04722121⟩).