Sewer Audit - Design Checklist Gravity sewers, sewage pumping stations and pressure sewers

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1 Question Relevant Clauses Design checked? Do the drawings show an appropriate revision history, and is 1.1 the design complete, checked and effectively ready for construction? 1.2 Has the whole catchment (required to be controlled through this development) been controlled as indicated in the Notice of Notice of Agreement for development Agreement? 1.3 Have any issues been identified for Survey Control? Survey Manual - Chapter 1, Survey Is the Australian Height Datum (A.H.D) noted on design plans? Responsibilities Section Is the Australian Map Grid (A.M.G) / Geocentric Datum of Survey Manual - Chapter 1, Survey Australia (G.D.A) noted on design plans? Responsibilities Section Are TBM's or PBM's shown on design plans and are AMG/GDA co-ordinates shown? Survey Manual - Chapter 1, Survey Responsibilities Section 2 Are you Auditing the design of Gravity Sewers, Rising Mains Do you wish to audit the alignment and location of Gravity Sewer, Rising Main or Siphons? - Have any issues been identified for Gravity Sewers, Rising Mains or Siphons? - Are all sewers aligned and offset as per SE Water requirements? (not located within the front boundaries of properties; located only in road reserves for 4.2.3, industrial/commercial areas; offsets; right angle crossings; etc.) Are all easements shown and do they comply with SE Water requirements? 4.2.5, Are all sewers located clear of the zone of influence of 4.3.4, 4.4.4, structures, or if not possible, has detailed analysis been Guidelines for Proposed Works undertaken and appropriate protection been specified and Over/Adjacent to Water Authority Assets approved by SE Water? up to and including 225mm diameter Are all curved sewers appropriately designed? (correct materials, minimum radius requirements, method of achieving curve, sufficient set out details etc.) 17.2, Is minimum cover achieved on all pipes? Are minimum clearances from other services achieved? Do any sewers cross over water mains? Does the design include details to ensure no crosscontamination can occur between the sewer and the water main? Are there any railway crossings or freeway crossings? Sewerage Code of Australia WSA , Melbourne Retail Water Agencies Edition Are all maintenance structures located out of the railway/freeway reserve? Does the alignment of the pipeline cross at right angles? 4.3.2, Does the location of the rising main comply with SE Water requirements? WSA Sewage Pump Station Code & SE Water P.S. Supp. Manual - Cl Has SE Water approval for installation of a Siphon been received? 7.8 Reviewed 20/6/2013 1

2 2.2 Do you wish to audit the Maintenance Structures? - Have any issues been identified for Maintenance Structures? Are all maintenance structures numbered in accordance with Survey Manual - Access Chamber standards? Numbering, page Does the distance between maintenance structures comply with standards (i.e. 150m in most cases)? Are maintenance structures shown at all the locations required by the standards, and has an appropriate type of structure 6.2, 6.7, Table 6.1 (MH, MS, TMS/IS) been nominated? Are minimum clearances to other structures/buildings achieved? Are correct diameters of maintenance holes nominated on design plans? Is the maintenance hole cover class noted on design plans? Is the area subject to flooding? - Are all cover levels of maintenance structures 150mm above the 1 in 5 year storm event level, and has approval been obtained for the use of bolt down covers? Has the correct maintenance hole type (conical, truncated, flat top, etc.) been specified for each maintenance hole? 6.6.1, 6.6.2, SEW Maintenance Hole Structures Technical Addendum Are the locations of all pre-cast manholes in accordance with standards? 6.6.2, Is detailed MH table design required to be submitted? (e.g. two or more internal drops, multiple incoming sewers, angle of deflection >90 o ) Are the MH table designs in accordance with standards? Are landings, portable standing planks, handgrips, ladders & step irons specified in accordance with standards, including correct materials for step irons? Is the grading through maintenance holes in accordance with standards? (min 30mm, effect of large deflections and steep grades, soffit to soffit design for different size pipes, etc.) Are structural computations provided for maintenance structures deeper than 6.0m? Commentary on SEW-1300 series drawings - maintenance structures Are there any gas check maintenance holes? - Are gas check manholes designed in accordance with the standard, including location in the road reserve, ultimately more than 50 lots connected, invert levels, changes of direction etc.? 7.2, 7.3, Are there any sewers or other underground structures to be built next to existing structures? Are guidance notes provided to the contractor for excavation next to existing manholes/structures to preserve stability during construction? - Are details of connections of new sewer pipes to all existing manholes provided? (pipe invert levels, angles between pipes, stepirons, access openings, and base details). Plans and section(s) to be included. 6.5, 6.6.6, 9.2.3(j) Reviewed 20/6/2013 2

3 2.3 Do you wish to audit the Hydraulic Design (gravity only)? Have any issues been identified for Hydraulic Design? - Are the correct pipe diameters specified in accordance with standards? 4.5.4, Does the grade of each pipe comply with standards? 4.5.4, Are any grades steeper than 1 in 10? Have trench stops been provided where required? 8.1 Is the velocity through the pipe below 3 m/s in accordance with the standard? Is the energy dissipated in the maintenance hole, and does the design incorporate measures to prevent hydraulic jumps? Has an Emergency Relief Structure (ERS) been incorporated in design? Have HGL details been submitted ensuring that there is no possibility of overflow upstream at MHs, property drains, etc, and are all other details in accordance with the standard? Where necessary, has ventilation been provided in accordance with the standard? Do you wish to audit Materials and Trench Design? - Have any issues been identified for Materials and Trench Design? Are all pipe materials, pipe classes, jointing methods etc. specified on design plans and are they all approved products? SE Water Approved Products List WSAA - Section Have any issues been identified with the trench details provided? Is the trench width provided or referred to relevant design standards? Are the particle size requirements and grading limits for embedment material provided? 8.9, Tables 30.1, 30.2, 30.3, and 30.4 (commentary on SEW-1200 Drawing Series) Flexible pipes: AS/NZS Part 1, AS/NZS Part 1 - Commentary, AS/NZS Part 2 RIGID PIPES: AS/NZS 3725, AS/NZS Commentary, AS , Tables 30.1, 30.2, 30.3, and 30.4 (commentary on SEW-1200 Drawing Series) Flexible pipes: AS/NZS Part 1, AS/NZS Part 1 - Commentary, AS/NZS Part 2 RIGID PIPES: AS/NZS 3725, AS/NZS Commentary, AS , 30.5 AS/NZS Part 2 SEW Technical Bulletin SEW Drawing SEW-1201 MRWA Backfill Specification Are backfill design specifications provided or referred to WSA code drawing or relevant standards? Are embedment types specified according to WSA standard 8, 30.2 drawings SEW-1202 to SEW-1205 or cross section details WSA SEW-1202 to WSA-1205 provided? Has a ground conditions report been provided where sewers are greater than 5m in depth? Are there wet or poor ground conditions, or any sewers greater 8.5 than DN 450? Has a specialist geotechnical assessment been made? Reviewed 20/6/2013 3

4 Has adequate trench design been made and relevant details provided? Have structural computations for the sewer pipe trench design been provided for sewers 600mm or larger? Have adequate details been provided for trenchless construction? 8.5, , 16.7, , 32.3 (commentary on drawings for buried crossings) Do you wish to audit issues related to Property Branches/Connections? - Have any issues been identified Property Branches/Connections? - Are all properties provided with a property branch/connection, 5.9, 6.6.4, 9.2.3(i) and is the type of branch/connection nominated on design Land development Manual plans? Is the depth for property connections, junctions and end fittings , 5.4 in accordance with the standard? Are property connection IO's located within property boundaries in accordance with the standard? SEW-1153-M & SEW-1154-M Do all property branches terminate 600mm (residential) or 1m Guidelines for Proposed Works (commercial/industrial) from any building lines or other Over/Adjacent to Water Authority Assets structures? up to and including 225mm diameter Are water seals (i.e. boundary traps) specified where required? 7.2, 7.3, Sewer Record Plan Is all partial lot control shown in accordance with the Notice of Agreement? , Notice of Agreement / Sewer Record Plan Where 10 or more units are to be connected to the sewer system, is it via a MH? Where spur branches / "Y" property connections are used, are they in accordance with the standard? Have any Type 2A or 4A property branches/connections been nominated? Are Type 2A and 4A property branches/connections used as per the standard? Are there any sewers equal to or greater than 300mm in diameter? Have any issues been identified for sewers greater than 300mm in diameter? Are self cleansing/slime stripping velocities achieved at PDWF? Are any sewers surcharging under 1 in 5 year floods (i.e. PWWF)? Are property connections only on sewers 450mm in dia. and less? 5.5.2, SEW Maintenance Hole Structures Technical Addendum 5.4, 5.7 & Reviewed 20/6/2013 4

5 2.7 Are any assets to be abandoned as part of the works? - Are details of treatment for assets that are to be abandoned included on the drawings? 2.8 Are there any Rising Mains? - Have any issues been identified for Rising Mains? Has the correct class, material etc. of pipe been specified on SE Water Sewage Pumping Station Supp. design plans? Manual - Cl Are all products specified approved by SE Water? SE Water Approved Products List Does the discharge point of the rising main comply with SE Water requirements and is it coated with an approved coating system for concrete? WSA Sewage Pumping Station Design Code & SE Water P.S. Supp. Manual - Cl Have scour valves been specified at suitable locations and comply with standards? WSA Sewage Pumping Station Design Code & SE Water P.S. Supp. Manual - Cl & & Standard Drawings SE Water_STD_ Have air relief valves been specified at suitable locations and comply with standards? Do velocities comply with SE Water requirements? Are there any anchor thrust blocks? Are details such as dimensions of the block concrete strength and reinforcement, and type of block specified on the layout plan? WSA Sewage Pumping Station Design Code & SE Water P.S. Supp. Manual - Cl & & Standard Drawing SE Water_STD_060 WSA Sewage Pumping Station Design Code & SE Water P.S. Supp. Manual - Cl Pressure Sewer Code of Australia Version 1.1 Section 9 and Standard drawings WAT WAT 1207 Pressure Sewer Code of Australia Version 1.1 Section 9 and Standard drawings WAT WAT Are all SE Water's requirements achieved? Does the Inverted Syphon design comply with the standard? Are all issues you wish to raise in Section 2 covered in the previous audit questions? Sewage Pumping Station Code of Australia WSA and SE Water S.P.S. Supplementary Manual 3 Are you Auditing the design of a Pumping Station? Do you wish to audit the design of the Wet Well, pipework and fittings? Is Pump Station a Package Pump Station? Does PS comply with requirements of WSAA purchase specification? SE Water Approved Products List Has a minimum of 2 PDWF emergency storage been provided between high level alarm and spill alarm? Do flotation calculations confirm a minimum FS of 1.1? Does coating of concrete surfaces comply with standard? SE Water Supp. Manual - Cl SE Water Technical Specification Coating systems for concrete in contact with sewage. Reviewed 20/6/2013 5

6 3.1.5 Is the wet well self draining? Are the covers in accordance with standards and are they arranged in a practical manner? Is the wet well diameter equal to or larger than the minimum allowable (i.e. min = 2.1m)? & Do the Cut-in/Cut-out volumes comply with SE Water requirements? Do wet well washers comply with standards? Does the Top Slab incorporate all below ground structures? Has the concrete strength been specified and does it comply with SE Water requirements? Is there clearance from overhead powerlines? SE Water Supp. Manual - Cl Do ladders comply with SE Water requirements and are they SE Water Supp. Manual - Standard accessible by removal of one lid? Drawing SE Water_STD_ Does the penstock (Knife Valve) comply with SE Water & Standard Drawing SE requirements? Water_STD_ Do all pipework comply with SE Water requirements (i.e. min dia. = 100mm)? Do all pipe supports comply with SE Water requirements? Standard Drawing SE Water_STD_ Does the pump well inlet pipe comply with SE Water requirements and is the inlet drop pipe submerged? (i.e. 2.5 & (h) 150mm above cut out level) Are computations for pump selection inclusive of NPV? SE Water Supp. Manual - Appendix C Are all pumps, pipeworks and fittings approved products? Has a flushing valve been incorporated into the design? SE Water Supp. Manual - Cl Do you wish to audit the Valve Chamber design? Is the pit accessible? Do all pipe supports comply with SE Water requirements? Standard Drawing SE Water_STD_ Are pressure main tappings in accordance with standards? Standard Drawing SE Water_STD_ Do ladders comply with SE Water requirements? SE Water Supp. Manual Standard Drawing SE Water_STD_ Has provision been made to operate valves without the need to remove the cover? Is the valve chamber self-draining? Are all valves clockwise closing? Do all pipeworks and fittings comply with standards? Does the emergency relief structure comply with the EPA protocol guidelines and standards? Flap gates and trap Standard Drawing SE Water_STD_061 for fats included in design? EPA Protocol ERS protocol approval received? Do you wish to audit the Ancillary Services? Does the water supply to the pumping station meet SE Water requirements (i.e. backflow prevention device)? SE Water Supp. Manual - Cl Does the access road comply with SE Water requirements? Standard Drawing SE Water_STD_ Have bollards been specified in accordance with standards? SE Water Supp. Manual Cl Reviewed 20/6/2013 6

7 3.4.4 Does site drainage comply with SE Water requirements? Does site security comply with SE Water requirements? & Are all issues you wish to raise in Section 3 covered in the previous audit questions? - Pressure Sewerage Code of Australia WSA and SE Water Pressure Sewer Supplementary Manual 4 Are you auditing the design of Pressure Sewers? 4.1 Have any issues been identified for pressure sewers? Are all pressure sewers located within road reserves and easements, and aligned as per SE Water requirements? 3.7 & Is minimum and maximum (1.5m) cover achieved on all pipes? Ch. 3.2 of SEW Supp Do offset's of the sewer comply with standards? Are there any railway crossings? Are all fittings located out of the railway reserve? Are there any freeway crossings? Does the alignment of the pipeline cross at right angles to the freeway? Are existing and proposed other services shown on the design plans? Table Are minimum clearances from other services achieved? Do you wish to audit components of the Hydraulic Design? - Have any issues been identified for Hydraulic Design? Are the correct pipe diameters specified in accordance with the 4.5 works agreement? Are all pipe materials, pipe classes (PN16), pipe colour, jointing methods etc. specified on design plans and are they all Ch of SEW Supp. approved products? Does the outlet of the design incorporate an appropriate discharge point? & Are duplicate mains used where necessary? Does the design verify that the pipe class meets the design pressures? Do the materials specified on the plans appear in the on the SEW approved products list or in the supplementary manual? Part 2 of SEW Supp Are the types of valves used noted on the plan? Are the valves in the appropriate location in accordance with SEW Specifications? Are the valves clockwise closing as noted on the plan? Does the plan include lockable flushing assemblies? Are the high and low points met in accordance with the SEW specifications? 3.2, 5.5 & Does the outlet discharge into a Manhole? Is the design of the manhole shown including epoxy coating design? Does the design of the discharge manhole prevent turbulent flow? Are tracer wires shown on the design plans? - Reviewed 20/6/2013 7

8 Does the design avoid the use of 90 degree deflections? Has the design longitudinal section been submitted with the plans? Do you wish to audit issues related to Property Branches/Connections? Have any issues been identified Property Branches/Connections? Are all properties provided with a property branch/connection and is the type of branch/connection nominated on design plans? Where a service connection is not required at this stage, will the alignment allow them to be possible in the future? Are ball valves used at the property connection point? & Are all issues you wish to raise in Section 4 covered in the previous audit questions? - Reviewed 20/6/2013 8