Creating and Editing the Model

The model can consist of up to six layers:

• three node layers: junctions, reservoirs and tanks

• three link layers: pipes, valve, and pumps

Each of the six objects is represented in QGIS by it’s own layer. Layers do not need to be created if they are not used for the model. There is a convenience function to create these empty layers with appropriate fields and some default styling, but any layer with the appropriate geometry type (points for nodes and linestrings for links) and with the minimum necessary fields can be used.

Creating Layers

You can use the ‘new’ button on the toolbar to create a set of layers with default properties.

Alternatively, for more control, you can use the ‘Create Template Layers’ processing tool.

It is also possible to use any layer - you do not have to use the layers created by the plugin.

Attributes

Attributes are based on the attributes within WNTR.

All attributes are optional, and unless otherwise stated will use WNTR default values if not defined.

Name All layers can optionally use the attribute name to give a name to each item, which will be visible on the output layer. This must be a string. If no name is given, it will be automatically generated.

Patterns All patterns are string fields. This can be left blank. Otherwise, it should be input as a series of numbers seperated by spaces:

1  1.2 1.3 0.8

Patterns will also accept a field of type list, where each item in the list is a number.

Curves Curves should be inputted with the following form, where each pair of numbers in brackets is an x, y point on the curve.

(0, 10), (2, 5), (3.3, 7)

Geographical attributes All geographical (coordinates, vertices) and network-related (start_node_name and end_node_name) WNTR attributes are not used. This is because they are calculated automatically based on the geometry of the features.

Table 2 Possible Junction Attributes

Attribute	QGIS Field Type	Value(s)	Used for
name	Text (string)	Will calculate if blank
elevation	Decimal (double)
base_demand	Decimal (double)
demand_pattern	Text (string) or Decimal list	Pattern
emitter_coefficient	Decimal (double)
initial_quality	Decimal (double)		Water Quality Analysis
minimum_pressure	Decimal (double)		Pressure Dependent Demand
required_pressure	Decimal (double)		Pressure Dependent Demand
pressure_exponent	Decimal (double)		Pressure Dependent Demand

Table 3 Possible Reservoir Attributes

Attribute	QGIS Field Type	Value(s)	Used for
name	Text (string)	Will calculate if blank
base_head	Decimal (double)
head_pattern	Text (string) or Decimal list	Pattern
initial_quality	Decimal (double)		Water Quality Analysis

Table 4 Possible Tank Attributes

Attribute	QGIS Field Type	Value(s)	Used for
name	Text (string)	Will calculate if blank
elevation	Decimal (double)
init_level	Decimal (double)
min_level	Decimal (double)
max_level	Decimal (double)
diameter	Decimal (double)
min_vol	Decimal (double)
vol_curve	Text (string)	Curve
overflow	Boolean
initial_quality	Decimal (double)		Water Quality Analysis
mixing_fraction	Decimal (double)		Water Quality Analysis
mixing_model	Decimal (double)		Water Quality Analysis
bulk_coeff	Decimal (double)		Water Quality Analysis

Table 5 Possible Pipes Attributes

Attribute	QGIS Field Type	Value(s)	Used for
name	Text (string)	Will calculate if blank
length	Decimal (double)	Will calculate if blank
diameter	Decimal (double)
roughness	Decimal (double)
minor_loss	Decimal (double)
initial_status	InitialStatus	OPEN, CLOSED
check_valve	Boolean
bulk_coeff	Decimal (double)		Water Quality Analysis
wall_coeff	Decimal (double)		Water Quality Analysis

Table 6 Possible Pumps Attributes

Attribute	QGIS Field Type	Value(s)	Used for
name	Text (string)	Will calculate if blank
pump_type	PumpTypes	POWER, HEAD
pump_curve	Text (string)	Curve
power	Decimal (double)
base_speed	Decimal (double)
speed_pattern	Text (string) or Decimal list	Pattern
initial_status	InitialStatus	OPEN, CLOSED
initial_setting	Decimal (double)
efficiency	Text (string)	Curve	Energy
energy_pattern	Text (string) or Decimal list	Pattern	Energy
energy_price	Decimal (double)		Energy

Table 7 Possible Valve Attributes

Attribute	QGIS Field Type	Value(s)	Used for
name	Text (string)	Will calculate if blank
diameter	Decimal (double)
valve_type	ValveType	PRV, PSV, PBV, FCV, TCV, GPV
minor_loss	Decimal (double)
initial_status	InitialStatus	ACTIVE, OPEN, CLOSED
initial_setting	Decimal (double)
headloss_curve	Text (string)	Curve