Finn Valley was engaged by the Midcoast Council for the restoration of a flood-damaged culvert and the reconstruction of the road embankment and shoulder along Bowman Farm Road. Situated in a northwest-southeast section, the site features an unsealed road built atop a fill formation over an ephemeral drainage gully. The culvert consists of a large diameter (approximately 1500mm) concrete pipe, surrounded by an earth fill batter with dense grass and weed vegetation.

Severe scouring resulted in the removal of the outer section of the embankment around the culvert outlet, revealing a fill profile composed of sandy gravelly clay with low plasticity. This caused the outer segment of the pipe to lose support, dropping into the scour void and becoming disengaged from the rest of the pipe within the embankment.

The project scope encompassed various tasks, including but not limited to:

• Locating and relocating existing public utility services.
• Maintaining the current roadway.
• Implementing permanent and temporary erosion and sedimentation controls.
• Removing the existing pipe and reinstalling it with a concrete bandage and no fines base to meet TfNSW

specifications.

• Conducting excavation and embankment reconstruction, including culvert restoration and constructing a 3-

meter-high gabion wall.

• Revegetating disturbed areas through seeding.

Given the impracticality of using large rocks as per the original design due to placement angles, an alternative solution was devised: the construction of a gabion basket-style headwall. This innovative approach allowed for maximum lane width without the need for additional pipes.

Ultimately, the project achieved success by effectively maximizing the road’s width without requiring additional pipe installations.