O'Regan Reserve - Waterway Restoration & Asset Protection

Overview The Hills Shire Council is seeking a lump sum tender from suitably qualified contractors for waterway restoration and asset protection works at O'Regan Reserve, Baulkham Hills. The works include creek-bank stabilisation, retaining walls, sewer protection, drainage and crossing reconstruction, rockwork and native revegetation. About Stevenson Creek emerges from the upstream stormwater outlet and flows through an incised corridor containing exposed bedrock, pools, existing riffles and eroding banks. Residential properties and public paths adjoin the work area. Retained native vegetation includes a sensitive Turpentine-Ironbark forest community, mature trees and established groundcovers. Live sewer lines, stormwater outlets and the existing crossing constrain excavation, plant movement and temporary facilities. Operational and emergency access to sewer assets must be maintained. Purpose The project addresses eroding creek banks, failing retaining structures, undermined stormwater outlets and exposed sewer assets along Stevenson Creek. The works are intended to retain the existing creek alignment and flow paths, protect adjoining properties and public paths, and restore disturbed ground. Scope The scope includes: Creek-bank stabilisation Construction of sandstone-log retaining walls to replace the failing upstream retaining structures, including foundations, no-fines backfill, drainage, the clay-lined swale and associated sewer protection Sewer protection works Drainage and crossing reconstruction Rockwork, including check dams, toe-boulder protection, rock riffles, cascades and outlet scour protection, while retaining designated bedrock, vegetation, pools and exposed sewer access Native revegetation Renewal of the nominated sections of Sewer Lines 2 and 5 Reconstruction of the failed stormwater outlets Replacement of the creek crossing, including associated safety rails and gravel maintenance track Rehabilitation of disturbed ground, with native planting, establishment and maintenance carried out to the vegetation plan Construction must account for live services, limited access, retained trees, public use and rainfall-related flows. The works must be carried out in accordance with the issued Revision 3 drawings dated 13 January 2026, the vegetation plan, the Construction Environmental Management Plan, asset-owner conditions and Council requirements.