LSC2025-47 - Culvert Replacement - Wilson Street, Wedderburn
Loddon Shire Council seek tenders from appropriately qualified and experienced contractors to replace and upgrade existing culvert at Wilson Street, Wedderburn.
Refer to construction drawings 8983.1 to 8983.10 for details on project and IDM standards - SD100, SD110, SD120, SD130, SD140, SD200, SD205, SD210, SD220, SD225, SD235, SD245, SD250, SD270 for kerb, footpath and crossing standards.
All works shall comply with VicRoads standard, the following VicRoads Standard sections apply to this contract C648 - NPWC-RC 160, 163, 166, 168, 176, 177, 201, 204, 610, 611, 614, 619, 707, 708, 709, 713, 801, & 818.Refer to the following link to VicRoads Standard Sections: Click here for link to VicRoads Standard Sections
The Scope of work is-
A. Culvert replacement, kerbs and channel, road works & ~50m Levee
Installation of upgraded Culvert, Kerb & Channel, road construction and levee construction (~50m) that falls in the road reserve.
B. ~15m in Crown land
Levee construction (~15m) that falls on crown land which may proceed subject to approval through the LUAA process.
The project will be evaluated based on option A only.
Option B selected only if approved.
2.1 General Notes
• Contractors must thoroughly review and comprehend all notes provided
• The contractor is required to perform a Before You Dig (BYD) investigation
• Conduct compressive strength tests for concrete and compaction tests for beddings/base/subbase as required.
• Submit (3 weeks) and obtain approval for traffic management plans from Council representative before commencing the project
• Ensure provision of at least three weeks' notice of the start date to facilitate newspaper advance notice prior to the commencement of works
• Council has engaged a Coliban Water registered consultant “Tomkinson Group” to supervise excavation works for locating the water main and to help determine if lowering of the water main is necessary. Tomkinson Group will liaise with Coliban Water as part of the permit process.
• A preliminary design for lowering the water mains is included in the tender document to help estimate potential costs. Ensure provision of subcontractor details (if applicable) and costs/hourly rates.
• If lowering the water main is required, the council will grant the contractor an appropriate extension of time
• An existing redundant asbestos pipe from Coliban Water must be disposed following all necessary safety measures. Licensed asbestos removal professionals must be engaged to do this work.
2.2 Project specific hold points
• Obtain approval for traffic management plans from the council representative before commencing the project
• Kick-off site meeting for culvert installation, underground asset protection discussion - Telstra and Coliban Water. The contractor is required to provide a Safe Work Method Statement (SWMS) before work can proceed.
• Approval required for the Licenced Asbestos remover (removal of old main)
• Once Telstra conduits are tied and suspended properly, Superintendent and/or representative to conduct site inspection and take/collect pictures to send to Telstra
• If water mains needs lowering, liaise with Coliban Water registered consultant “Tomkinson Group”
• Before backfilling, if 600mm cover between top of Telstra conduits and finished levels(s) is not achievable, details of concrete protection slab or better protection measure must be approved by Telstra and Superintendent
• Provide test results for slab bedding for culvert, further works can only progress once test result is approved by council representative
• Rebar’s for base slab, drop structure and wing walls must be inspected before concreting works
• Proof roll test before sealing
2.3 Culvert replacement, road works & ~50m Levee
i. Excavation works
• Remove and dispose of the existing twin pipe culvert (900mm diameter) and all associated works including removal of tree.
• Excavate to required depth to install culvert base slab. Use proper slope protection measures and appropriate excavation method to protect Telstra and Coliban Water assets.
ii. Telstra cables relocation (Addition to Telstra notes in drawing 8983.2)
• Relocate the existing Telstra Cable (P50) and Telstra optic fibre conduit (P100). Refer to Telstra notes in the drawing for details. It is the contractor's responsibility to follow Telstra guidelines/notes to protect Telstra assets.
• Crown units must be installed below the existing Telstra conduits.
• Contractor to keep photographic documentation. Capturing all steps and submit it to council project manager.
• Backfilling shall only commence following inspection from Telstra
• If Telstra assets are damaged for any reason, the contractor must contact the Council Superintendents representative and Telstra representative.
• Mechanical protection, such as minimum protective slab details, is attached with the tender documents if required.
iii. Water Mains Lowering (if required)
• Hydro excavation was conducted at two locations near the intersection of Tantalla and Wilson Street, revealing depths of 3.3m and 2.2m. However, the depth of the existing water mains could not be confirmed. Following consultation with Coliban Water, the depth remains undetermined. Due to the uncertainty, the council initiated a Developer Installed Works process and has engaged a Coliban Water registered consultant for a contingency design for lowering the water main to avoid construction delays if required.
• Preliminary/verified design from Coliban Water for lowering the water mains is attached with this tender document to estimate potential costs. Ensure provision of any subcontractor details (if applicable)
• The contractor is required to liaise with the consultant “Tomkinson” and council representative during excavation works.
iv. Culvert Installation and associated works
• Ensure provision of a minimum depth of 200mm bedding for the base slab with Class 3 FCR to a minimum of 98% MDD
• A cast-in-situ concrete base slab
• Install 31.2m long 2400(W) x 1200(D) mm crown units (considering each crown unit length of 2.4m, 13 crown units are needed). Cast-in-situ wing walls, apron at downstream and cast-in-situ drop structure, apron and wing wall at upstream (refer to drawing numbers 8983.3 and 8983.4)
• Place type 2, grouted rock beaching (approx. 60m² U/S and approx.. 25m2 D/S) with robust needle-punched non-woven geotextile as per VicRoads standard, section 713, as shown in drawing 8983.2
• Provide 150mm bitac or approved equivalent over all joints
• Provide permeable fill or approved geo-membrane as specified in the construction drawings
• The designed upstream (U/S) culvert invert is 186.650m and the designed downstream (D/S) culvert invert is 186.400m
• Install bi-directional hazard markers as located in the drawing and as per Australian Standard AS 1742.2 (D4-2-3)
• Install four pedestrian crossings as per AS 1428.1, IDM standard SD200, and TGIS as per AS 1428.4
• Install guide posts with delineators on all four corners of the culvert. Delineators shall be as specified in AS 1742.2
• Provide compacted clean fill on both U/S and D/S of the culvert as shown in drawing 8983.3 and 40mm Class 4 FCR or reclaimed sandy gravel/gravelly sand compacted to not less than 98% modified compaction AS1289.5.2.1 under road section which typically acts as subgrade for road.
v. Road works (Seal Area 800m2)
• Install kerb outlet as specified in the drawing
• Install B2 type kerb on both sides as specified in drawing 8983.9
• Reinstate existing B2 kerb on both sides for a length of 1.5m as shown in drawing 8983.2
• 180mm thick subbase course with 20mm Class 3 FCR, compacted to not less than 98% modified compaction AS 1289.5.2
• 120mm thick base course with 20mm Class 2 FCR, compacted to not less than 98% modified compaction AS 1289.5.2
• 10/6 double seal for road surface (Note: Road cross-fall changes with chainage, refer cross-section details for cross-fall, cut and fill, and levels in drawing numbers 8983.7 to 8983.9)
vi. ~50m Levee construction (Levee in road reserve)
• Install ~50m levee bank maintaining the slope as in the drawing 8983.5 and heights as in drawing 8983.10
• Fill with suitable clay fill and compact it to 98% SDD
vii. ~15m Levee construction (only if approved)
• Install ~15m levee bank maintaining the slope as in the drawing 8983.5 and heights as in drawing 8983.10
• Fill with suitable clay fill and compact it to 98% SDD
2.4 Attachments
1. Combined drawings
2. Telstra minimum protective slab drawing
3. Water main lowering preliminary design