LARGE-SCALE SITES
Grazing land management
All sites had fencing maintained in working order during the monitoring period. One site maintained total cattle exclusion since the works were undertaken in 2020. The other four sites excluded cattle for at least two wet seasons and then grazed strategically in the dry season to promote vegetation growth( i. e. to reduce the height of old grass and stimulate new growth). There were moderate impacts from feral deer at Sites 2, 3 and 4, particularly during the early stages of vegetation establishment( pers comm. landholder).
Maintenance
Some maintenance was undertaken at all five large‐scale sites prior to the start of the Monitoring and Maintenance project in 2022( i. e. most occurred after the 2021 wet season). Sites 1 and 5 received additional maintenance during the life of the project( 2022-2024).
Components of the site works that required and received maintenance were: seven reshaped areas, five rock chutes, four porous check dams, one bund and one cut off wall( Figure 7). The need to repair rills in the reshaped areas was common with seven of the eight areas affected. This damage was mostly caused by direct rainfall on recently reshaped, ameliorated and seeded gully slopes and was most prevalent after the 2021 wet season( Figure 8). Seven of the 12 rock chutes required maintenance, and this involved repairing the earthen abutments or removing tunnels at the edges of the rock chute. Four of the 84 porous check dams required maintenance. This was usually because they had filled, retaining maximum sediment and then outflanked. Like the rills in the reshaped areas, most check dam outflanking happened in the first wet season after construction.
Reshape, ameliorants, reveg, irrigate |
0 0 |
No Maintenance |
Maintenance |
Reshape, ameliorants, reveg 1 7
Reshape, fertiliser, seed
Reshape, seed
Contour line rehab – catchment
0 0
0 0
2 0
Rock chute 5 7
Porous check dams / weirs 80 4
Bund 4 1
Bank and spreader – catchment 0 0
Cut off wall 5 1
Stick line
0 0
0 20 40 60 80 100
Figure 7. The number of erosion control structures and treatments at large-scale sites that received maintenance compared to those that did not( post-construction up until December 2024).
20 GULLY MAINTENANCE AND MONITORING TECHNICAL REPORT