RED BARN ESTATE, HANMER SPRINGS

PROJECT OVERVIEW

Ongrade Drainage & Excavation was engaged to deliver full civil and underground infrastructure works for Stage 1 of the Red Barn Estate subdivision in Hanmer Springs.

Stage 1
Site clearance and preparation works, including stripping of topsoil across building platforms, berms, flood channels, and basin areas, along with associated earthworks and ground preparation.

Earthworks & Site Shaping

Bulk earthworks comprising over 16,000m³ of imported engineered fill, sourced from local river supplies, placed, conditioned, and compacted to specification, along with associated cut to fill operations and final shaping of residential lots, accessways, and open space areas.
Construction of flood management infrastructure including formed flood channels, box culverts, rock-lined channels, geofabric installation, turf matting, access tracks, and associated erosion protection works.
Construction of the first flush basin, including excavation, lining systems, access tracks, and finishing works, with extensive dewatering required to manage groundwater and maintain dry working conditions during construction.

Wastewater

Installation of wastewater infrastructure including over 225m of sewer mains (DN225 and DN150 PVC-U), along with approximately 95m of DN100 sewer service connections.
Wastewater works were undertaken on a live sewer network, including the main outfall serving the Hanmer Springs township, requiring the implementation of temporary overpumping systems to maintain uninterrupted service during construction.
Construction and modification of wastewater structures including manholes, drop structures, vented lids, and low-pressure sewer components, with full testing and commissioning.

Stormwater

Installation of a comprehensive stormwater network including over 330m of stormwater pipework (RCRRJ and PVC-U up to Ø375), stormwater service connections, outfalls with rockwall protection, and child-proof grates.
Construction of stormwater structures including manholes, double sumps, corner sumps, junctions, and full system testing and CCTV inspection.
Installation of potable water infrastructure including approximately 400m of water mains (DN180 and DN63 PE), installed both in dedicated trenches and common service corridors.
Installation of water supply fittings and connections including hydrants, sluice valves, gate valves, thrust blocks, service connections, meter boxes, and chlorination points, with full testing and commissioning.

Associated Civil Works

Construction of entrance roading and pedestrian infrastructure including kerb and flat channel, asphalt surfacing, footpaths, tactile paving, and associated pavement layers.
Installation of common service trenches for power, fibre, and communications services across the subdivision.