Structure L7 (log sill and rock weir) regenerating well in early summer, December 2023.

In December 2023, Senior Landscape Planner Jack Smart visited the ‘Lorrina’ property near Braidwood, NSW, to monitor a suite of in-stream structures installed six months earlier. These log-sill and rock weir structures are slowing water flows in the creek and creating new ponding zones. The results after six months are very positive.

Vegetation has increased across the whole site, particularly aquatic vegetation within and beside the ponds. There is also plenty of vegetation growing on the structures themselves. Its continued growth will ensure the long-term stability of the structures and support many processes beneficial to the creek and the wider landscape: the deposition of sediment behind the structures, improved stream water quality and a gradual increase in the bed level of the channel. This natural regeneration will be boosted by a revegetation project the landholders are planning for the riparian corridor in autumn, 2024.

The ‘Lorrina’ project is already illustrating what can be achieved with well-designed landscape rehydration interventions: we’re delighted to see this landscape’s transformation! Mulloon Consulting will be monitoring the site every six months to track the change.

A series of comparison photos is provided below for a number of the Lorrina structures comparing sites before works commenced, sites just after works were constructed and sites six months post-intervention.

(click on photos to enlarge and toggle through each set)

Above: Structure L2 (log sill and rock weir): before works commenced, just after works were constructed, 6 months post-intervention.

Above: Structures L3.1, L3.2 and L3.3 (series of small rock weirs); before works commenced, just after works were constructed, 6 months post-intervention.

Above: Structure L3.4 (rock weir); before works commenced (looking downstream), just after works were constructed (looking upstream), 6 months post-intervention (looking upstream).