About the NCEA network appraisal tool

• Zooming in and out is possible using the + and - buttons or the mouse wheel
• The map can be displayed in vector format. Vector maps are high quality images suitable for reproduction in a report (by snipping or screenshot)
• Panning is possible using the hand icon
• Information (satellite image, river network, hydrometric areas, EA Areas) can be added to the map or removed via the layer icon (at the bottom left of the map)
• Spatial data can be added when sufficiently zoomed in (bedrock hydrogeology, superficial geology, elevation, land cover and rainfall).
• Station catchment polygons are available to view on the map for public NRFA stations only (use NRFA public symbology). Click on an NRFA public station on the map to view its popup, which has the Show/hide catchment button.

• Filters are provided for a large suite of metadata parameters as dropdowns under the following categories:
  • Basic (including Location, EA Area, Record length)
  • NRFA data types (Peak flow, Daily flow, Live data)
  • Location (including Easting, Northing and Station level)
  • Category (FEH Suitability)
  • Station information (Station type, Sensitivity, Co-located index sites and Co-located with)
  • Catchment information (including Factors affecting runoff)
  • Daily flow statistics (including FDC statistics, Completeness, base flow index)
  • Peak flow statistics (including QMED, Peak flow start date)
  • Elevation (Min, Max and 10th, 50th and 90th centiles)
  • Catchment rainfall (SAAR4170, SAAR6190, SAAR8110)
  • Land cover (Arable/horticultural, Grassland, Mountain/heath/bog, Woodland, Urban)
  • Geology (high/moderate/low permeability bedrock, high/low/mixed permeability superficial deposits)
  • FEH Descriptors (including BFIHOST and FARL)
  • Sub-networks (including UK Benchmark, etc)
• Having selected the parameter, select a range/condition to apply via the dropdown box (e.g between, is missing), and then “Add filter”
• Multiple filters can be added to build a query, and any of these removed using the “x” next to the filter (e.g. GSDQ overall class = G, Figure 2).

• Columns displayed in the table under the map can be added and removed via the button, and columns are automatically added when selected as a filter
• Each catchment/gauging station meeting the current filter criteria has a row in the table. The table will update whenever the filter criteria are changed, and the number of catchments meeting the filter criteria is shown above the table
• The table can be sorted by any column by double clicking on the column heading
• The table is searchable and can be downloaded using the controls above the header row
• To download all available metadata for all catchments/gauging stations, use the 'Select all' button at the bottom of the column selection window, and remove any filters before downloading to csv
  

• Using the dropdown at the top of the Network Appraisal Tool, select a parameter that will be used to categorise/classify the metadata, and colour code the map and graphics.
• Parameters available for symbology are categorical rather than numerical, such as FEH Suitability and NRFA data type
• When any parameter is selected for symbology, graphics beneath the main metadata table show the numbers of catchments/gauging stations in each category/class for the whole table.
  

• Under the metadata table, select a parameter to plot as a histogram for the filtered catchments/gauging stations
• To toggle between the histogram and cumulative distribution plot, using the 'Cumulative' tick box above the plot
• Pop up information is available on each bar of the histogram by hovering over it
• Further options are available by hovering at the top right corner of the plot, including the download of the bins and distributions as a .csv file
• All plots are zoomable, by dragging and releasing the left mouse button. To return to the original settings, double click on the plot, or use the 'reset axes' button.

• Having plotted a histogram of a selected parameter (x), select a second parameter (y) to generate the scatter plot from the dropdown 'Draw scatter plot of (x) vs (y)'
• A third parameter (z) can be added to generate a three dimensional scatter plot using the 'Add to scatter plot (z)' dropdown. This can be rotated to visualise the relationships between the three parameters from any angle
• The same plotting options are available as for the histograms, plus the additional functionality of hovering over points to identify individual catchments/gauging stations
• Additional plotting options are available, to the top right of the 3D scatter plot

Once a histogram has been plotted, the distribution of a parameter for a subset of filtered gauging station catchments can be compared to that of all river catchments in England by clicking the 'Compare to all England rivers (all cells)' tickbox above the histogram

As for a single histogram the 'Cumulative' tickbox' can be used to toggle between histogram and cumulative distribution plots, and both the plot and underlying data are downloadable