Modelling the water supply system

In InfoWorks WS Pro, the modelling of the water supply system is divided into two main parts:

• Networks represent the fixed physical network. The network describes all the aspects of the system that do not change over the short term period being analysed. The elements of the network are:
  • sources of water
  • water treatment plants
  • pumping stations
  • reservoirs and water towers
  • pipelines
  • service connections
  • control equipment, for example valves and pumps
• Control data sets describe the way the water supply network is operated:
  • operation of control equipment
  • managing levels in reservoirs and water towers
  • maintaining service levels

The physical network

The physical network is the static geometry of the system. The InfoWorks model of the network is made up of nodes (reservoirs, customer supply points) and links (pipes, valves, pumping stations). To model the network, the user will need to gather information about the real network and then identify the nodes and links for the model. See Networks for more information.

New networks are created within a model group. Or you can import networks from an external system.

A network is a version controlled item. See Managing version controlled objects.

If you are maintaining a network over a period of time, it can be updated with additional asset or other data stored in CSV files.

When you open a network it is initially displayed using a GeoPlan window. The GeoPlan shows the network in its geographical context. You can then view or edit the network objects that make up the network.

Networks can also be exported in a variety of formats.

See Networks and Managing version controlled objects for full details on working with networks.

Network objects

Networks are made up of network objects. These are:

• Nodes - Simple nodes, transfer nodes, fixed head nodes and reservoirs
• Links - Pipes, valves and pumping stations

Full details about working with network objects can be found in the Network objects section.

Network views

There are several different ways of viewing and editing network information:

• The GeoPlan window is the one you will probably use most. The network is displayed in geographical form, and you can also display other layers of data such as background maps.
• The grid views provide tabular access to most of the data about objects in the network. There is a separate grid view for each object type. Some data, such as tabular data, cannot be displayed. For more details, see Network object grid views.
• The long section view displays a vertical schematic of a series of nodes and links within the network.
• The property sheets allow you to view and edit all details about an individual network object.

Control and operation

Every water supply system must have a control policy. In InfoWorks WS Pro the network geometry and control data are split into separate but very closely related items. The control data describes the initial state of the water supply network at the start of a simulation and the policy for controlling the network during the simulation.

This separation simplifies the modelling process. Multiple control data sets can be associated with the same network to model variations in operation. The same control data can be associated with more than one network so physical changes in the network can be modelled.

Control data is also a version controlled item. Creating is the same process but importing is different because data is needed from other sources. Control data does not require validation before being used in a simulation. See Managing version controlled objects.

Control data can be updated from external CSV files.

The major difference is opening control data for viewing and editing. Control data cannot be viewed on its own. It can only be viewed or edited in the context of a network. You have to associate the control data with a network. It will be displayed in parallel with the network on the same grid views and property sheets.

Note: If control data refers to a network object that does not exist in the network, that control data will be ignored and will not be displayed. It may, however, cause simulations to fail.

See Control data and Managing version controlled objects for full details on working with control data.

Note: There is so much overlap between the geometry and control data that all the information about control data for individual network objects can be found in the individual sections under Network objects. The main topic describes both geometry and control issues. The Data Fields pages describe both geometry and control fields for the objects.

Further information

It is beyond the remit of this on-line help to describe the general approaches to model making. Some excellent pointers can be found in Chapter 6 of Obradovic et al (1998), entitled Making a Model.