Two high level water reservoirs in Toowoomba require renewal work.

The works generally include:

1) Gabbinbar HLR22 – 31 Nelson Street (access from Nelson Street), Toowoomba

a. This is a concrete floor/wall reservoir with evidence of cracking in the wall to floor joints. There is efflorescence on the walls inside the tower, indicating leaks have been present for some time. This reservoir should receive a watertight internal coating and supporting works in line with Scope Item 1 from Table E1.

b. The existing roof is single crossfall zincalume roof. Water is presently pooling around the access hatch, causing a contamination risk. While repair may be possible, when viewed in combination with the other defects, it’s Council’s preference that the roof and supporting structure is replaced at this time.

c. The internal ladders and platform are aluminium and are corroding at a significant rate. A new internal FRP ladder is required inside the water filled tank section. This ladder will primarily be accessed by dive contractors. As such, it is Councils preference for the ladder to be a vertical, single fall type extending to the bottom of the tank. The ladder should be provided with stile extensions and should not be fitted with a ladder cage.

d. The hatch must be replaced with one consistent with TRC’s CIV-006 standard drawings (DM#11494801) and be coupled with a grid-mesh platform around all edges. Handrailing must be provided around this raised platform and the interface with existing external ladder platform will need to be made compliant with AS1657.

2) Freneau Pines HLR16 – 2 Poplar Street (access from Poplar Street), Toowoomba

a. This is a concrete panel floor/wall and roof reservoir. This reservoir has a bladder lining that has failed and will require removal and disposal by the Contractor. This reservoir may either be relined with a similar style to the existing bladder, or coated internally if the Contractor deems this option suitable.

Additional remediation works are required to the external concrete surface of this reservoir. For detailed remedial works description please refer to Reference Documentation - Freneau Pines HL R16 - Reports - DOCs#10519741 GHD structural assessment report Section 3.1, subsection 2b and 2c.

b. This reservoir will require some access rectifications in line with scope item 2 from Table E1, though a full roof replacement is not required.

The existing roof hatch is not watertight and must be replaced. Unsecured flashing and exposed cable entries must be appropriately sealed to prevent contamination. The contractor must also supply and install a lockable door for the existing internal doorway at the top of the internal reservoir chute as required, preventing unauthorised access.

Refer to Annexure E for full scope of works.

A compulsory pre-tender meeting on site is to be undertaken by the offeror for the offer to be considered conforming. To arrange a meeting, contact Doug Jesshope – Doug.Jesshope@tr.qld.gov.au or 07 4688 6995