The Statistics panel for the display of groundwater data in the TMWSA is visible right at the start of the map (“Deep dive” dashboard) or when clicking the Statistics button (“Quick view” dashboard) on the right hand side of the map/browser. It may be switched off (to see more of the map) or on by clicking the Statistics button at the bottom of the Main toolbar to the left.
The Statistics panel is divided into three sections (from top to bottom):
A general button and selection section with buttons for accessing the Help and Disclaimer pages and a Locate/Search drop-down to select specific monitoring areas of the project area. The button under the drop-down clears any previously selected areas and resets the locate/search to all monitoring areas, which is the default on start-up. Selecting any of the monitoring areas will change the statistics information and charts below this section.
The next section is a statistics section with various blocks of statistical water level information extracted directly from the database. This information is dynamic and may change periodically as new data is added to the database and therefore may take a second or two to load after selecting a monitoring area with the Locate drop-down.
In the bottom section are various line and/or bar charts representing relevant information extracted “live” from the database. The charts change according to the monitoring area selected in the Locate drop-down.
A few important notes on these statistics:
The initial statistics and charts represent groundwater and/or rainfall conditions for the total TMWSA project area and are only a very generalised presentation. The map user is reminded that e.g. water levels in the central and eastern TMWSA area (Cape Flats Aquifer) are generally shallower than in the more mountainous western areas of Newlands and the Table Mountain. Statistics over the total area may therefore not be representative or used for generalisation in a particular smaller area.
The “Last 3 months” statistics block may show no water level values, which may be caused by the fact that recent data (the last 3 months) data has not been uploaded yet. The “Latest” block therefore may represent a water level that is older than 3 months!
The monitoring areas are switched off by default on map start-up, but will be switched on as soon as any monitoring area is selected in the “Locate” drop-down. In that case only the selected monitoring area will be shown and zoomed to on the map. When checking in the Layers panel the Monitoring Areas layer is highlighted, indicating that a filter is active for this layer. Clicking on the small filter icon on the top right of the Layers panel will “Deactivate the current filter” and show all monitoring areas again.
Although a Monthly Rainfall chart may be shown at the bottom of the Statistics panel the Rainfall monitoring layer may not be active (shown on the map). This layer, which is a pie chart representation of monthly rainfalls per rainfall station, and may be switched on/off in the Layers panel.
If you find any errors or omissions or have questions about these statistics, please send an email to immo[AT]blecher.co.za.