[en] The Posiva Flow Log/Difference Flow Method can be used for a relatively fast determination of water conductivity and hydraulic head in fractures/fractured zones in cored drillholes. In this method, a flow meter with a flow guide is used. This report presents the principles and results of the measurements carried out in drillholes OL-KR1, -KR2, -KR4, -KR7, -KR8, -KR10, -KR14, -KR22, -KR22B, -KR27 and -KR28 at the Olkiluoto investigation site during the year 2006. These measurements are a part of the Olkiluoto monitoring programme. Two different section lengths (2 m and 0.5 m) were used in the flow logging measurements. The flow into the drillhole or from the drillhole into the bedrock was measured within the section. Measurements were carried out both in natural conditions and when the drillhole was pumped. The transmissivity (T) and hydraulic head (h) of zones were calculated and are presented in the results. The measurement device also includes a sensor for single-point resistance (SPR) measurements. SPR was always measured in connection with flow measurements. SPR is measured when the tool is moving. The electric conductivity of fracture-specific water (EC) was measured in selected fractures in some of the drillholes. The fractures were chosen on the basis of the measured flow from the fracture to the drillhole. In addition to this some previously selected fractures were measured. The EC of the drillhole water was measured separately. (orig.)