Vacuum, Step, Pressure Sewer, Gravity, Hybrid - Which Technology to Use?

A significant number of wastewater reticulation technologies are available; each with varying attributes, costs and benefits. Assessment of these technologies is simplified when considering greenfield areas where generally only the network and trunk assets needs to be considered. However, when considering reticulation of existing communities, the specific attributes and costs of connecting individual existing properties can add an additional layer of complexity to the assessment. The costs and risks associated with the physical connection of each property have the ability to add significant cost to a project and mean an alternative reticulation technology may provide the least cost solution.

This paper considers how the attributes of existing properties can impact upon the preferred reticulation technology through cost, risk and practicality. A methodology is presented to facilitate the quantitative assessment of each individual property in the catchment and how this assessment can be used to optimise the selection of the final wastewater reticulation technology and network configuration.