Water samples were collected from Pohjanpitäjänlahti bay in May 2021 from four stations along a coastal salinity gradient. Absorption coefficients at wavelengths 200-800 nm were measured for colored dissolved organic matter (CDOM) analyses from the water samples. The samples were collected 8 times straight to plastic bottles from a small boat. The data was collected to a thesis funded by Walter and Andreé de Nottbeck Foundation.