Water Services Trust Fund The Urban Projects Concept (UPC) Implementation Workshop Quality of Works 1

Why Emphasise Quality? To promote use of water in a hygienic environment For sustainability and durability For returns on investment Image of the WSP among the public 2

Lessons from the WSTF Pilot Projects Quality of construction works was largely affected by: 1.Weak supervision 2.Lack of adherence to technical specifications 3.Sloppy and incompetent Contractors 4.Theft of materials 5.Varying site conditions 3

Quality of works: Examples of “Don'ts” Poor finishing Evidence of poor concrete mix Neglect of the water kiosk Evidence that drawings were not followed No angle bars 4

Examples of “Don'ts” (cont’d) Incomplete work Poorly done soak pit Gulley trap is uncovered Accumulation of solid waste Unkempt surroundings Uncovered; posing a hazard 5

Examples of “Don'ts” (cont’d) Poor concreting (ELDOWASS) Short kicker bars (NZOWASCO) 6

Examples of “Don'ts” (cont’d) Unacceptable poor quality of columns (NZOWASCO) Unacceptable result of using poor materials (NZOWASCO) 7

Examples of “Don'ts” (cont’d) Leakage Wrong material usage Poor quality improvising 8

0 Examples of “Don'ts (cont’d) Poor plumbing Prone to rain water Lack of repair works 9

Examples of “Don'ts” (cont’d) Poor drainage around kiosk Effect of leaking tank on roof slab 10

How Do We Ensure Quality? 1.Following construction guidelines and the Toolkit 2.Drawings and specifications 3.Routine inspections 4.Testing and approval of materials 5.Ensuring safe and healthy environment 11

Technical Specifications 1.Materials Rejection of substandard materials Examination of all materials arriving on site- should fit the specifications Handling and storing materials with care 2.Codes of practice Reference to be made to relevant codes of practice: (BS 8110, BS 5950, BS 6399, BS 4466 etc.) 12

Technical Specifications (cont’d) 3.Drawings All technical drawings to be accurately adhered to A set of the drawings must be provided on site at all times 4.Setting Out Works shall be set out accurately WSP to establish and locate all benchmarks, lines, boundaries and/ or levels on the ground 5.The Site Accessible; with secure storage for materials and plant The works should not adversely interfere with the environment 13

Technical Specifications (cont’d) 6.Concrete Mix concrete in specified ratios at the site Approved mechanical means of handling concrete are encouraged Concrete should be placed in single operation to the full thickness of slabs and beams and similar members Concrete in columns should be carefully placed and well vibrated Work cube tests recommended 14

Technical Specifications (cont’d) 7.Curing of Concrete Protect concrete from premature drying by protection from wind, sun or rain by sheeting, or other approved means Wet the concrete continuously for 14 days 8.Reinforcement Fabrication, bending and fixing of reinforcement should be in accordance with standards Shall be free from rust, grease or any substance likely to reduce the bond between steel and concrete 15

Technical Specifications…cont’d 10. Finishes Painting and other finishes to be carried out on clean surfaces According to specifications 11. Fittings High quality plumbing parts required; especially gate valves, bends and taps Right class of pipes should be used 16

Supervision of Labour 1.Competence Workers on site should be experienced Removal of incompetent labour encouraged 2.Approval Work done shall be subject to approval by Engineer Engineer to ensure that works are complete before payment 17

Supervision of Labour (cont’d) 3.Drawings Workers should be able to interpret all drawings 4.Safety & Health Safety and health needs of workers should be addressed 18

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