A model that contains the geometry of new drainage components to be implemented during a rail project.

These models are prepared as the basis for the contractors planned work, to ensure that the contractor has the necessary information to accurately and correctly place their drainage components and structures.

The model is used during the design process to define location and geometry and must include the necessary elements to generate drawings and calculate quantities. The models are also to be used for collision control against the rail’s clearance profile.

General requirements for 3D modelling of drainage are set out in the CAD manual Appendix, section