A turbidity sensor comprising: a quasi-collimated light source having a length and being configured to provide quasi-collimated light (Lc) to a liquid sample and a linear sensor array ; wherein the liquid sample is arranged in relation to the light source and the linear sensor array so as to reflect light (Lr) off suspended matter in the liquid sample; the linear sensor array having rows and columns of optical elements and configured to sense light reflected off suspended matter in the liquid sample along the length of the quasi-collimated light source and provide signaling containing information about the light (Lr) reflected off the suspended matter; characterized in that the linear sensor array is configured such that the reflected light (Lr) undergoes an attenuation across the linear sensor array , including along the length and width of the linear sensor array , following Beer's law, thereby creating a spatial gradient containing information regarding the concentration of the turbidity, and a signal processor or processing module configured to: receive the signaling; and determine corresponding signaling containing information about a concentration of turbidity of the liquid, based upon the signaling received, based upon the attenuation of the reflected light (Lr) sensed across the linear sensor array , and further based upon the spatial gradient of the reflected light (Lr) sensed across the linear sensor array . a quasi-collimated light source having a length and being configured to provide quasi-collimated light (Lc) to a liquid sample and a linear sensor array ; wherein the liquid sample is arranged in relation to the light source and the linear sensor array so as to reflect light (Lr) off suspended matter in the liquid sample; the linear sensor array having rows and columns of optical elements and configured to sense light reflected off suspended matter in the liquid sample along the length of the quasi-collimated light source and provide signaling containing information about the light (Lr) reflected off the suspended matter; characterized in that the linear sensor array is configured such that the reflected light (Lr) undergoes an attenuation across the linear sensor array , including along the length and width of the linear sensor array , following Beer's law, thereby creating a spatial gradient containing information regarding the concentration of the turbidity, and a signal processor or processing module configured to: receive the signaling; and determine corresponding signaling containing information about a concentration of turbidity of the liquid, based upon the signaling received, based upon the attenuation of the reflected light (Lr) sensed across the linear sensor array , and further based upon the spatial gradient of the reflected light (Lr) sensed across the linear sensor array . receive the signaling; and determine corresponding signaling containing information about a concentration of turbidity of the liquid, based upon the signaling received, based upon the attenuation of the reflected light (Lr) sensed across the linear sensor array , and further based upon the spatial gradient of the reflected light (Lr) sensed across the linear sensor array . <EOS>