4.2. Gauge node

A Gauge node either represents a physical recording device that measures river levels at a point in a river or a logical point in a river model where you need to be able to record and view the modelled flow. Gauge nodes are used in conjunction with rating curves to estimate flows for a particular location. You can use a Gauge node for model calibration and verification, by comparing observed and predicted flow.

The Bureau of Meteorology (BOM) station identifier can be set from the station list visible in Feature Editor 2. Find and select the station name in the list and click OK.

If you have a time series for the physical gauge location, you can load it into the Gauge node by clicking Load. Table 2 shows the file format. You can visualise the gauge data in the feature editor or by clicking the Graph button. This opens a separate window where you can also inspect the underlying data. However, the data is only for your own reference. It plays no part in the running of the model. Data files of this kind do not stipulate units. You select the appropriate units using the Units: drop-down menu. Click Clear to disconnect a data source from the Gauge node.

The Set Flow checkbox results in the modelled flow at a gauge being overridden by the gauge flow. This forces the modelled flow to equal observed flow. Additionally, enabling the Set Flow checkbox converts a Gauge node to an Unaccounted Difference node (Feature Editor 3). This is used in operations environments to check for differences in water balances on links.

A rating curve converts a flow into a level, producing an output of level (Feature Editor 4). You would often have recorded gauge level at a gauge rather than flow. So, it is useful for calibration.

Ownership - This functionality is yet to be documented. If you would like assistance, please call 1300-5-WATER (1300-592-837) (indicative cross-reference: in Ownership).

Unaccounted Difference - This functionality is yet to be documented. If you would like assistance, please call 1300-5-WATER (1300-592-837)

Forecast - this is similar to the recession forecast model in the Inflow node. Refer to Forecasting inflows.

Constituents - This functionality is yet to be documented. If you would like assistance, please call 1300-5-WATER (1300-592-837).

The use of Constituent Forecasting is discussed in the chapter on Forecasting.

Where: date is the date of observation in dd/mm/yyyy format (eg 31-12-2000)
value is the observed value (eg 2600).