Theory

The Sewer Analysis and Design module is a complete tool for the design of foul water or sewerage networks. It calculates the invert levels, slopes and diameters of the culverts; as well as the design flow, capacity and flow velocity of each culvert.

The program models a network consisting of both existing and new culverts. Any culverts that do not have a size, invert level and/or slope are automatically designed according to the design parameters.

In most cases, multiple inflows can be specified at each node. Inflows can be user-defined in the inflow parameters tables.

The program simulates a complex system of local storage (surge tanks) and overflows, thereby enabling you to model the intricate networks that are typical of modern cities. The network size is only limited to your hard drive capacity.

Each model can have multiple sub-networks and outfalls. You can specify the outfall levels if you want to connect to existing systems. Alternatively, the program determines the best possible outfall level in accordance with the design parameters.

The Guidelines for the Provision of Engineering Services in Residential Townships, published by the Department of Community Development, have been followed in the calculation of unit flows.

In addition, the design flows can also be calculated according to the Harmon formula, or using unit inflow hydrographs. A brief discussion on each method of flow determination is included.

The design is controlled by a number of parameters that are set by the user. This function allows the design to be tailored to your own requirements, or those of the local authorities or councils.