Slope exceedance analysis

Red Falls rehabilitation slope report

Exceedance detected
Data: RGB aerial data captured 24 Jan 2026 by Reece Fraser
Exceeds threshold
28.1%
Proportion of area of interest exceeding the 15% threshold (1.1 ha).
Within threshold
71.9%
Proportion of area of interest within the 15% threshold (2.8 ha).
Critical erosion risk
0.5 ha
Amount of area within the highest exceedance band (>=30%).
Priority sites
5
Field check required.
1.08 haat risk
15-20%
20-25%
25-30%
>=30%
15-20%
0.25 ha
23.4%
20-25%
0.16 ha
15.1%
25-30%
0.11 ha
9.8%
>=30%
0.54 ha
50.0%
28.1% of AOI exceeds the 15% threshold
1.08 ha of the 3.86 ha AOI exceeds the slope threshold. Industry benchmarks typically target <10% exceedance for stable revegetation on rehabilitated surfaces.
Highest exceedance band (>=30%): 0.54 ha - elevated erosion risk
Slopes in the highest exceedance band carry increased erosion risk regardless of ground cover. Physical intervention - rock armouring, erosion matting, or regrading - is recommended before revegetation in these areas.
71.9% of AOI within threshold
The majority of the site is below the erosion threshold and suitable for standard revegetation management without additional earthworks.
Priority 1
Priority 2
Priority 3
Priority 4
Priority 5

The base map is a generic reference image and does not show the drone data used to create this report. Some visual differences may appear because the base map can be older than the drone survey.

ZoneArea (ha)Exceeds (%)IndexDominant categorySeverity
Polygon 10.6346.0%1.32>=30%Moderate exceedance
Polygon 20.632.5%0.0415-20%Mild exceedance
Polygon 30.633.0%0.0415-20%Mild exceedance
Polygon 40.6319.2%0.57>=30%Moderate exceedance
Polygon 50.6364.2%1.84>=30%Substantial exceedance
Polygon 60.6333.7%0.96>=30%Moderate exceedance
Priority sites for field check

Scope note

This report summarises slope exceedance indicators derived from mapped topographic surfaces and threshold-based area calculations. These outputs help prioritise locations for field review and erosion-risk intervention, but they do not by themselves establish causation, geotechnical stability, rehabilitation success, or a complete management prescription. In the absence of LiDAR data, areas with dense vegetation may show inaccurate slope classifications. Ground verification, local drainage context, and site-specific engineering judgement should be considered alongside this report before intervention decisions are finalised.