A method of measuring tides and inland water levels is provided. The method comprises a computer receiving a first measurement of an angle formed by a first ray comprising a vertical fixed piling and a second ray formed by a downward sloping ramp of known length, a lower end of the ramp contacting a surface of a dock float and the surface representing a plane contacting the fixed piling at a 90-degree angle at a first meeting point. The computer then calculates, based on the first measurement, based on the ramp length, and based on the 90-degree angle, a first distance from the first meeting point to a vertex of the angle. The computer later receives a second measurement of the angle, wherein the plane meets the piling at a second meeting point. The computer calculates a second distance and expressing a difference between two distances as tidal change.