The results of long-term (2007–2013) year-round continuous temperature measurements in the near-bottom water and the top sediment layer of a small shallow lake are reported. The measurement technique using a bottom-mounted platform is described. Owing to the highly sensitive equipment used in the long-term water temperature measurements with a small time step (one minute) we managed to obtain fundamentally new information on heat transfer through the water-sediment interface throughout the year, including the periods of ice cover formation and destruction.