Methods and systems for determining a thickness of a substance on a surface of a body of water are described. The methods and systems utilize a thickness detection apparatus that includes a body and at least one camera. The body has a plurality of sides with at least a portion of one of the sides comprising a light transmitting material. At least one camera is disposed within the body and configured to generate at least one image through the light transmitting material of the substances extending a depth below an air-substance interface.