PART 1 PLANNING & DESIGN

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1 1.1 Scope The Supplementary Manual sets out the QUU requirements for sewers up to and including DN 300. References to sewers larger than DN 300 are provided for information only Planning responsibilities QUU is generally responsible for overall planning for the provision of sewerage to its customers. Delete the last sentence Unless otherwise..., or particular requirements of the Water Agency Design Responsibilities Design responsibilities shall comply with: Pt Assessment of Future Future loads shall be assessed as given in Cl below. Loads 2.4 Sewage Quality For operational reasons, swimming pool discharges including backwash from either commercial or domestic pools shall not be discharged to the sewerage reticulation system Design Flow Estimation The design flow shall be estimated as follows: Pt Method - General 4.1 Detail Design Process Multi-unit developments shall be serviced by a 160 diameter property connection. Internal works shall be constructed as private sanitary drainage. Multi-unit developments, that are redeveloped under a future reconfiguration, to have individual units located on a freehold title lot, will require each of the lots to be serviced with a 110 diameter property connection. This may involve the construction of a sewerage reticulation system to provide a property connection to each lot. Where this could occur consideration should be given to constructing the private sanitary drainage to the sewer standards. Provision for sewerage connection to upstream properties has to be provided Sewer Layout The preferred sewer location shall comply with: Pt Environmental Considerations Full details of environmental mitigation works shall be shown on the Design Drawings and submitted to relevant authority for approval. Prior to any works being accepted the consulting engineer shall provide QUU delegate with certification that the works have been carried out in accordance with any environmental requirements Contaminated Sites A register of contaminated sites is held by the DERM Contaminated Land Unit. Details of works to be carried out on a contaminated site shall be referred to the Council Environmental Officer Easements In general, easements are not required for gravity sewers Disused Sewers Where sewers, MH s, or MSs will no longer be required, Pt the remedial works shall comply with: Horizontal Alignment - The sewer alignment shall comply with: Pt Roads, Reserves and Open Space Railway Reserves Where a sewer is to be located within a railway reserve, a Deed of Agreement between the Railway Authority and QUU is required. Date of Issue: November 2011 QUU Requirements to WSA 02 Part 1 Page 1 of 5

2 4.3.4 Public and Private Sewer locations shall comply with: Pt Property Horizontal Curves in Sewers. Horizontal curves in sewers shall comply with: Pt Clearances from Transmission Towers and Power Lines Clearance from Building Over or Near Sewers (BOS) Underground Obstructions & Services Minimum Air Space for Ventilation Minimum Pipe Sizes for Maintenance Purposes Maximum EP for Sewers Table Minimum Grades for Self-Cleansing Vertical Alignment of Sewers - General Minimum Cover Over Sewers -Table Lot servicing requirements - General Serviced Area Requirements for Residential Lots Serviced Area Requirements for Industrial and Commercial lots Minimum Depth of Sewer Connection Point Internal fall through MHs joining sewers of same diameter Where the distance between a metal sewer and a power line or transmission tower falls within the distances stated in the Code, a report on the procedures to be adopted for the construction and maintenance of the sewer shall be provided and signed by a RPEQ as conforming with all relevant regulations etc. Clearances from structures, retaining walls and trees shall Pt comply with: Building over or near sewers shall comply with: Pt Clearances shall comply with: Pt Select option B. The flow depth at the Design Flow (PWWF) shall not exceed 70 % of the Diameter in depth. Amend Table 4.3 to comply with: Pt Sewers shall be sized to carry the design flow without exceeding the 70% flow depth. The maximum EP figures in Table 4.4 shall not apply. Where possible, the average self-cleansing velocity as Pt described in this Clause shall be 1 m/s. Amend Table 4.6 and 4.7 to comply with: Sewers and property connections shall be constructed at the shallowest practicable depth, while ensuring that the critical factors described in the clause are achieved. Amend Table 4.8 to comply with: Pt Where filling of a site is proposed as a way of controlling or increasing control of a lot, the filling will be subject to separate approval from the relevant authority. For single residential lots, the property connection shall service the total area of the lot. For lots with multiple residential units, QUU may consider partial lot servicing. For battle axe blocks the serviced area may be considered to start at the end of the access way. For industrial and commercial lots, QUU may consider partial lot servicing. The minimum depth of the property connection point invert shall comply with: The minimum internal fall through a MS on a PE system shall be: Deflection angle Minimum fall 0 45 o 20mm o 40mm Pt Date of Issue: November 2011 QUU Requirements to WSA 02 Part 1 Page 2 of 5

3 Large falls at MHs. Table 4.10 No internal drops are permitted in a DN 900 MH. A maximum of one internal drop is permitted in a DN 1200 MH Vertical Curves Vertical curves in sewers shall comply with: Pt Compound Curves A maximum of one compound long radius bend with a maximum vertical deflection angle of 30 0 is permitted between adjacent maintenance structures External Corrosion NuSewers and PVC sewers shall not be used in ground likely to be contaminated with hydrocarbons. 5.3 Property Connections The two standard connection options presented do not apply. Nusewer connections shall comply with the details given in the QUU Drg. No s 486/5/25- SP002/1, 2/2 2/3 and 2/ Maximum Depth of Property Connections The maximum depth of property connections shall comply with: Multiple Occupancy Lots The arrangement in sub-clause b is not permitted. 5.6 Location of Connection Points Property connections shall not be located within 1.5m of existing or proposed structures. Pt Undeveloped Lots The preferred location of the property connection OB is 1.2m from the downstream lot boundary, where this is not possible, the OB shall not be further than 3.5 m from the downstream boundary. Note it is our preference that all sewers are outside Developed Lots Refer to Cl above. 5.7 Y Property Connections Property connection configurations shall comply with: Pt Length of Property Connection sewers Types of Maintenance 6.2 Locations of Maintenance Spacing of Maintenance Maximum length of a property connection sewer shall be 25 m. PE Sediment Traps PE sediment traps for Nusewers shall comply with: Pt Maintenance Structure Spacing-Reticulation Sewers 6.4 Special Considerations in Locating Maintenance Types of MH construction Types of maintenance structures shall comply with: Pt Redrawn Table 6.1: Pt The design shall ensure that access to every part of the sewer can be achieved with jet rodder equipment assuming the service vehicle is fitted with pressure hoses with a minimum length of 150 m. The spacing of maintenance structures shall comply with: Pt Clearances to maintenance structures, ends of line and property connections shall be within a 3m x 2m clear area open to the sky. They shall not be located within a building, or underneath a building overhang. Precast concrete MH s are not acceptable except as formwork. Concrete for MH construction shall be special class to WSA PS Diameters of MH s MH diameters shall comply with: Pt Ladders, Step irons and Details shall comply with: Pt Landings A2 Date of Issue: November 2011 QUU Requirements to WSA 02 Part 1 Page 3 of 5

4 6.6.9 MH Covers MH covers shall comply with: Pt Modifications to Existing MH s Design Parameters for MSs and TMs 7.2 Water Seals, Boundary Traps and Water-Sealed MHs Horizontal directional drilling (HDD)- Design requirements HDD Acceptance criteria Design parameters for inverted syphons Modifications to MH s shall comply with: Pt The design for MSs and TMs shall comply with: Pt Generally water seals or water-sealed MHs as per WSAA drawings SEW-1409, SEW-1410 or SEW-1411 are not required. Change the term Near-Horizontal Boreholes to Horizontal Directional Drilling (HDD) throughout the Clause 7.6. In sub paragraph (A) change reference Table 6.1 to Table 7.1 HDD may be approved by QUU/Delegate subject, but not be limited to, the following criteria: (a) Preferred pipe material is PE100. Mechanical or E-F couplings shall not be used within boreholes. (b) Diameter to be 1 size larger than that determined by the following the requirements of Section 3 and 4. (c) Pipe class to be minimum 2 classes up than that determined by the following the requirements of Section 3 and 4. Consulting engineers/contractors are responsible to ascertain & confirm pipe classes to suit required construction forces according to the pipe length, pipe diameter, pipe construction wear & tear and equipments etc. (d) Minimum grade to be the value given in Table 4.6 plus 0.5%. (e) The full pipe length shall be pressure tested as per Clause (f) Check for ponding with water followed by CCTV inspections. (g) If there is ponding found by CCTV, consulting engineers/contactors shall carry out a calculation to ensure that the ultimate PDWF level as designed will not exceed 70% of the pipe diameter at the ponded section in depth. (h) If above requirements are not met, consulting engineers/contractors shall excavate & make good or abandon the pipes and start the installation again. Before any approvals can be granted, the consulting engineer/contractor shall agree in writing to accept the requirements as per points (g) & (h) above. Replace the sub paragraph (ix): (ix) The inlet structure shall be designed so that only the primary barrel comes into operation for flows up to PDWF (with a provision of freeboard), and the secondary barrels are brought into service for increased flows i.e. PWWF. 8.2 Products and Materials Restrictions on the use of PE sewers (NuSewers) shall apply in the following situations: Pt A2 A1 A1 Date of Issue: November 2011 QUU Requirements to WSA 02 Part 1 Page 4 of 5

5 Creek Crossing All sewers crossing a creek shall comply with: Pt Bulkheads and Bulkheads and trenchstops shall comply with: Pt Trenchstops 9.2 Design Drawings The Design Drawings shall include: Pt Drafting Standards Drafting standards shall comply with: Pt Scale An appropriate scale shall be selected for the locality plan such that the content described in CL 9.2 above can be clearly shown. Date of Issue: November 2011 QUU Requirements to WSA 02 Part 1 Page 5 of 5