With the current growing size of cities, it is difficult to realize real-time inspections of fixed municipal facilities by manual inspections. There are various ways to realize automated inspections of municipal facilities, but these methods usually focus only on the state of the municipal facilities themselves, ignoring the negative impacts of peripheral obstacles on safety and availability. Therefore, this paper proposes a monocular camera-based algorithm for inspecting obstacles around municipal facilities. This algorithm estimates the pose of known inspection objects in the image, thereby inverting the spatial information. In addition, to reduce the cost of dataset acquisition, this paper also proposes an algorithm for generating a dataset for position estimation using Blender. The method in this paper can fully utilize the cameras on the existing inspection equipment to achieve the inspection of obstacles around municipal facilities without incurring additional hardware costs.