Herein, to address the challenge in measuring the small-angle backscattering intensity of water bodies, the water Scheimpflug lidar system was designed based on the Scheimpflug imaging principle. The design, simulation, and construction of this water Scheimpflug lidar were presented, and the flume experiments were conducted on deionized water, tap water, and river water. Moreover, the distance correction method under the condition of multi-measurement media was discussed in detail. The variations in width and intensity of the backscattered beam were compared with the measured data by the spectrophotometer. Results indicate that the width and intensity of a laser beam can represent the beam attenuation and simultaneously characterize the backscattered optical intensities in different water bodies. Furthermore, the data from the spectrophotometer have a good consistency with those from the water Scheimpflug lidar system.