Getting Started

This tool helps you calculate Biodiversity Net Gain (BNG) for development sites using the Small Sites Metric (SSM) methodology.

Step 1: Map Navigation

• Use the mouse to pan around the map
• Use the scroll wheel to zoom in and out
• Use the search box in the top-right to find locations

Step 2: Layer Controls

• Use the left panel to control map layers
• Toggle layers on/off using the switches
• Adjust layer opacity using the sliders
• Click the arrow button to collapse/expand the panel

Step 3: Drawing Development Site

• Click "Draw Development Site" in the right panel
• Click on the map to create polygon vertices
• Double-click to complete the polygon
• Use "Clear" to remove the polygon and start over

Step 4: Calculating BNG

• After drawing your site, click "Calculate BNG"
• The results will show in the right panel
• Results include:
  • Site area in hectares
  • Biodiversity units
  • Net gain percentage
  • Protected sites present
  • Priority habitats count

Understanding the Results

• Protected sites are shown in red if present
• A minimum 10% net gain is required
• The calculation considers:
  • Habitat distinctiveness
  • Habitat condition
  • Strategic significance
  • Protected sites and priority habitats

Tips

• Zoom in for more accurate drawing
• Check all relevant layers before calculating
• Use the opacity controls to see overlapping features
• Click on features to see detailed information