Diversion banks stop erosion, increase infiltration
Diversion banks constructed above the head of a gully has halted the progress of the gully head. Water is now being held in the landscape by the banks, instead of running into the gully system improving water infiltration.
Rehydrating landscapes is about making use of what little water there is, and reinstating the hydrological processes to return landscapes to as close as possible to their original state. This means filling the sponge (storing water) under the bit of country that is being reinstated.
Landscape rehydration works include (but are not limited to) activities such as:
- Leaky weirs.
- Rock ramps.
- Contour banks.
- Watercourse plantings.
When complemented by a controlled grazing management plan, the outcomes can include eroded areas being restored, improved ecological health, improved water quality and increased productive capacity of the grazing landscape.
This case study shows how Dartmoor Station, near Collinsville, is rehydrating the landscape to build resilience and improve productivity. The Mulloon Institute designed cost-effective works to stop an actively eroding gully head encroaching onto productive grazing land.
Grazing Naturally has provided advice and oversight of the implementation of a rotational grazing plan that combines observing the environment and responding appropriately with livestock management.
A gully head was encroaching onto productive grazing land.
A series of rehydration banks, each about 200 metres long, were constructed above the head of a gully. The aim was to halt the progress of the gully head.
Water is now being held in the landscape by the banks instead of running into the gully system, improving water infiltration. The area was seeded with native grasses (in 2021) prior to the wet season.
Early indications are positive. Water is being held in the landscape following the wet season. A complementary grazing management plan has been implemented to improve ground cover and soil health.
Total fine sediment reduction from the treated site on Dartmoor was 16t/y.
This was complemented by minor works on another part of the property that included the construction of diversion banks, ripping and soil amelioration that has resulted in a fine sediment reduction of 27t/y