WMS:HY-12

The US Federal Highway Administration's HY-12 is a DOS-based storm drain analysis program that can be used for designing inlets, pipes, and the general layout of a storm drain network. An HY-12 model can be generated by drawing the proposed pipe and inlet locations in a storm drain coverage. Then the map module locations are converted to a 1D schematic where the HY-12 model parameters are defined. Many of the HY-12 computations, such as channel calculations, curb and gutter calculations, and rational method computations, are based on computations in FHWA's Hydraulic Toolbox software. You can refer to the documentation in both the Hydraulic Toolbox and in HY-12 to learn about the specific computation methods used in HY-12.

This tutorial shows you how to model and design a storm drain network in a small suburban sub-basin. You learn how to assign pipe invert, access hole, ground, and inlet elevations to your model. You also learn how to associate computed hydrologic model data with rational method data so it can be used in HY-12. It is recommended that you be familiar with some of the more advanced watershed modeling techniques in WMS by following the advanced watershed modeling tutorial before attempting this one.