PART 3. CLAUSE WSA (Hunter Water Edition) Version 2 WSA (Hunter Water Edition) Version 1 General Comment

Transcription

1 WSA Water Supply Code of Australia (unter Water Edition) ersion 1 Part 4 Comparison with WSA Water Supply Code of Australia (unter Water Edition ) ersion 2 Part 3 General Comment W 25 Introduction W 25.1 General Delete Standard Drawings wherever appearing and insert Drawings Insert new 2 nd paragraph as follows: PART 3 The Drawings refer to recycled water throughout as an example of non-drinking water. 4th paragraph delete and do not apply to any particular Water Agency (Refer to the individual Water Agency for their legend, symbol and layout requirements) and insert although they have been based on drawings supplied by Gold Coast Water and Sydney Water Standard Drawings are included in the Water Supply Code of Australia to assist in understanding of the principles and methodology involved in construction of water supply systems and to enhance the design and construction parts of this Code. The Drawings should be read in conjunction with the balance of the Code. The Drawings included in this Part of the Code provide deemed-to-comply solutions for the installation of most elements of a water supply system. owever, they will not suit all circumstances or overcome all problems. To meet special needs, Designers and Constructors are encouraged to identify improved construction methods and other variations from the requirements set out in the Standard Drawings. Authorisation by the local Water Agency will be necessary before any major departure from the principles outlined in the drawings are implemented. Successful initiatives will be considered by WSAA for inclusion in future editions of this Code. All Design Drawings should include the name of the Water Agency and have a signature block to allow confirmation that each drawing complies with Water Agency requirements. The symbols and markings used on these Drawings are typical only and do not apply to any particular Water Agency (Refer to the individual Water Agency for their legend, symbol and layout requirements). Individual Water Agencies may have specific information and presentation requirements, which should be determined before commencing any project. Any additional information, layout or format requirements specified by the Water Agency take precedence over these Drawings. All special requirements including, but not limited to geotechnical requirements, embedment and compaction details, should be shown in the Design Drawings and/or the Specification. W 25.2 Drawing Commentary This informative commentary preceding the Drawings provides background information on the purpose and content of the Standard Drawings and serves as a general guide for Designers and Constructors, as well as a training aid. The use of separate commentary avoids excessive detail and complexity in the Drawing notes. The Designer is responsible for ensuring that Design Drawings and Specifications clearly address the issues of a particular project. It is the Designer s responsibility to provide detailed requirements such as trench depth, embedment and fill materials, concrete type and reinforcement in the Design Drawings. Both the Designer and Constructor should understand information relevant to selecting a feasible solution to a design and/or construction problem. Many of the Standard Drawings are typical and are not suitable for use without further design detail. W 25.3 aried Standard Drawings In some WSAA Standard Drawings, changes have been made to notes and/or technical detail to ensure the Drawings conform to unter Water requirements. Such varied drawings replace the original WSAA Standard Drawing. The varied drawing bears the same WAT prefix and number but with an added - suffix. Page 1 of 17

2 No WSAA Standard Drawing has been varied if the only necessary change is the addition of a - suffix to the number of another drawing cross-referenced within the notes or elsewhere on that Drawing. Notwithstanding, in such cases the varied unter Water version of such cross - referenced drawing shall be followed. W 25.4 Supplementary (Additional) Drawings The WSAA Standard Drawings have been supplemented with a number of additional Drawings. Such Drawings address aspects not otherwise covered by the WSAA Standard Drawings. Supplementary drawings complement and in some instances may replace WSAA Standard Drawings. Supplementary drawings are differentiated from WAT drawings by number and a - suffix. W 25.5 unter Water Reference Drawings (Superseded Standard Construction Practice Series) A small number of superseded unter Water Drawings are published on the unter Water website ( / Suppliers / Standard Drawings). They are identified generally by the words Standard Construction Practice WATER STANDARD in the title block and a WCP prefix on the drawing number. They are for reference purposes only and the detail shown is not mandated. Accredited Designers may refer to these drawings, in conjunction with the WAT series of Standard Drawings, to assist in developing concept and detail Design Drawings, typically where WAT Standard Drawings do not address a specific project requirement or provide sufficient detail. W 26 Listing of Standard Drawings Delete existing clause Insert new clause as follows: DRAWING NUMBER PIPELINE LAYOUT ACTIITY TITLE WAT Typical Mains Construction Reticulation Main Arrangements WAT Typical Mains Construction Distribution and Transfer Mains WAT Typical Mains Construction DN 63 PE Cul-de-Sac Arrangement WAT Typical Mains Construction Connection to Existing Mains WAT Property Services Single Service Main to Meter WAT Property Services Split Service Main to Meter WAT Property Services Connection to Main WAT Property Services Above Ground Meter Assembly Arrangement WAT Water Main Symbols WAT Design Layouts Typical Locality Plan WAT Design Layouts Typical Site Plan WAT Design Layouts Utility Services Space Allocations in Footway unter Water Area EMBEDMENT / TRENCFILL AND RESTRAINTS WAT 1200 Soil Classification Guidelines And Allowable Bearing Pressures for Anchors a Thrust Blocks WAT Embedment & Trenchfill Typical Arrangement WAT 1202 Standard Embedment All Pipe Types DRAWING NUMBER PIPELINE LAYOUT ACTIITY TITLE WAT 1100* Design Layouts Typical Locality Plan WAT 1101* Design Layouts Typical Site Plan WAT WAT WAT WAT WAT WAT WAT WAT WAT WAT Equivalent 1999 DRAWING NUMBER Typical Mains Construction Reticulation Main Arrangements WAT 200 WAT 201 Typical Mains Construction Distribution and Transfer Mains Typical Mains Construction DN 63 PE Cul-de-Sac Arrangement WAT 202 Typical Mains Construction Connection to Existing Mains Property Services Single Service Main to Meter WAT 300 Property Services Split Service Main to Meter WAT 301 Property Services Connection to Main WAT 302 Property Services Water Main Symbols Design Layouts Above Ground Meter Assembly Arrangement Typical Locality Plan WAT 303 Page 2 of 17

3 WAT 1203 Special Embedments Inadequate and Poor Foundation WAT Special Embedments Concrete, Geotextile and Cement Stabilised Systems WAT Thrust Block Details Concrete Blocks WAT Thrust and Anchor Blocks Gate alves and ertical Bends WAT 1208 Restrained Joint System DN 100 to DN 375 DI Mains WAT 1209 Trench Drainage Bulkheads and Trenchstop WAT 1210 Trench Drainage Typical Systems WAT Typical alve & ydrant Installation alve Arrangement WAT Typical alve & ydrant Installation ydrants and Air Relief alves WAT Typical Surface Fitting Installation Gate alve Surface Boxes Non Trafficable WAT Typical Surface Fitting Installation Gate alve Surface Boxes Trafficable WAT Typical Surface Fitting Installation ydrant Surface Boxes Trafficable and Non Trafficable WAT Typical Surface Fitting Installation ydrant Surface Boxes Trafficable WAT Typical Appurtenance Installation Scour Arrangements WAT Typical Appurtenance Installation alve Chambers WAT Typical Appurtenance Installation Pressure Reducing alves (PR) WAT Aerial Crossings Aqueduct WAT 1311 Aerial Crossings Aqueduct Protection Grille WAT 1312 Aerial Crossings Bridge Crossing Concepts WAT 1313 Flanged Joints Bolting Details WAT Typical Appurtenance Installation alve Gearbox Chamber for ertical Type Gate alve & Bypass in Footway WAT Typical Appurtenance Installation alve Gearbox Chamber for ertical Type Gate alve & Bypass in Carriageway FABRICATION DETAILS WAT 1400 Typical Steel Pipe Jointing Butt Welding of Joints WAT WAT Design Layouts Design Layouts EMBEDMENT / TRENCFILL AND RESTRAINTS Typical Site Plan Utility Services Space Allocations in Footways unter Water Area WAT 1200 Soil Classification Guidelines And Allowable Bearing Pressures for Anchors and Thrust Blocks WAT WAT 400 Embedment & Trenchfill Typical Arrangement WAT 100 WAT Buried Crossings Under Obstructions WAT 1202 Standard Embedment All Pipe Types WAT Buried Crossings Major Roadways WAT 1203 Special Embedments Inadequate and Poor Foundation WAT 101 WAT Buried Crossings Railways WAT Special Embedments Concrete, Geotextile and Cement WAT 102 WAT Buried Crossings Bored & Jacked Encasing Pipe Details Stabilised Systems WAT Standard Trench Details Reticulation Mains DN 100 to DN 375 WAT 1205 Thrust Block Details Concrete Blocks WAT 203 WAT Standard Trench Details WAT 1206* Transfer and Distribution Mains DN 300 to DN 750 Thrust Block Details Timber & Recycled Plastic Blocks WAT 204 WAT Thrust Block Details DN 450 to DN 750 Mains WAT Thrust and Anchor Blocks Gate alves and ertical Bends WAT 205 WAT Anchorage Details Stop alve Installations up to DN 1200 SCL Mains WAT 1208 Restrained Joint System DN 100 to DN 375 DI Mains WAT Anchorage Details Stop alve Installations up to DN 750 DICL Mains WAT 1209 Trench Drainage Bulkheads and Trenchstop WAT 103 WAT Buried Crossings Under Minor Obstructions WAT 1210 Trench Drainage Typical Systems WAT 104 INSTALLATION PRACTICES / STRUCTURES WAT Buried Crossings Under Obstructions WAT 105 WAT alve and ydrant Identification Identification Markers & Marker Posts WAT WAT WAT WAT WAT WAT Buried Crossings Major Roadways WAT 106 Buried Crossings Railways WAT 107 Buried Crossings Bored & Jacked Encasing Pipe Details Standard Trench Details Reticulation Mains DN 100 to DN 375 Standard Trench Details Transfer and Distribution Mains DN 300 to DN 750 Thrust Block Details EMBEDMENT / TRENCFILL AND RESTRAINTS continued WAT WAT WAT DN 450 to DN 750 Mains Anchorage Details Stop alve Installations up to DN 1200 SCL Mains Anchorage Details Stop alve Installations up to DN 750 DICL Mains Buried Crossings INSTALLATION PRACTICES/ STRUCTURES WAT Aerial Crossings Circular RC Piers in Non Flood Conditions for DN WAT to DN 750 Mains WAT Under Minor Obstructions alve and ydrant Identification Identification Markers & Marker Posts WAT 207 Typical alve & ydrant Installation alve Arrangement WAT 206 Page 3 of 17

4 WAT Typical Steel Pipe Jointing Rubber Ring Joint Spigot Bands WAT 1402 Typical Steel Pipe Jointing Welded Pipe Collars WAT 1403 Typical Steel Fabrication Bends WAT 1404 Typical Steel Fabrication Access Opening for Pipes DN 750 WAT 1405 Typical Steel Fabrication Dismantling and Flexible Joints WAT Typical Steel Fabrication alve Connection & Bypass WAT DI Installation alve Bypass Arrangement DI and GRP Pipe WAT Joint Corrosion Protection Cement Mortar Lined Steel Pipe DN 300 to DN 1200 WAT 1409 ydrant Installation Fittings PE Assemblies WAT WAT Typical Steel Pipe Jointing Welding of Existing Lead and Rubber Ring Joints WAT DUAL WATER SUPPLY SYSTEM WAT 1800 Typical Mains Construction Reticulation Main Arrangement for Dual Water Supply Systems WAT 1801 Typical Mains Construction Main Arrangement for Cul-de-sacs and Court Bowls WAT 1802 Typical Mains Construction Offtake Main Details WAT 1803 Property Services Typical Service Layouts and Alternative Marking Systems WAT 1804 Property Services Typical Service Arrangement WAT 1805 Property Services Standard Tapping Methods WAT 1806 Property Services Single and Split Services Across Carriageways WAT 1807 Property Services Typical Above-Ground Meter Arrangements WAT 1808 Property Services Typical In-Ground Meter Arrangement WAT 1810 Embedment and Trench Fill Main Arrangement for Dual Water Supply Systems WAT 1811 Thrust Block Details Concrete Thrust Blocks for Adjacent Dual Water Mains WAT 1820 ydrant Identification Identification Markers and Marker Posts WAT 1821 alve Identification Identification Markers and Marker Posts WAT 1822 Typical Appurtenance Installation ydrant alve and Flushing Installation on PE Mains using Compression Fittings WAT 1823 Typical Appurtenance Installation ydrant, alve and Flushing Installation on PE Mains using Electrofusion Fittings WAT 1824 Typical Appurtenance Installation Temporary Cross Connections WAT 1825 Typical Recycled Water Surface Fittings Marking and Colour Identification WAT WAT WAT WAT WAT WAT WAT Typical alve & ydrant Installation ydrants and Air Relief alves WAT 206 WAT 210 Typical Surface Fitting Installation Typical Surface Fitting Installation Typical Surface Fitting Installation Typical Surface Fitting Installation Gate alve Surface Boxes Non Trafficable Gate alve Surface Boxes Trafficable ydrant Surface Boxes Trafficable and Non Trafficable ydrant Surface Boxes Trafficable WAT 208 WAT 209 Typical Appurtenance Installation Scour Arrangements WAT 211 Typical Appurtenance Installation alve Chambers Typical Appurtenance Installation Pressure Reducing alves (PR) WAT 213 Aerial Crossings Aqueduct WAT 108 WAT 1311 Aerial Crossings Aqueduct Protection Grille WAT 109 WAT 1312 Aerial Crossings Bridge Crossing Concepts WAT 1313 Flanged Joints Bolting Details WAT WAT WAT Typical Appurtenance Installation Typical Appurtenance Installation Aerial Crossings FABRICATION DETAILS alve Gearbox Chamber for ertical Type Gate alve & Bypass in Footway alve Gearbox Chamber for ertical Type Gate alve & Bypass in Carriageway Circular RC Piers in Non Flood Conditions for DN 100 to DN 750 Mains WAT 1400 Typical Steel Pipe Jointing Butt Welding of Joints WAT Typical Steel Pipe Jointing Rubber Ring Joint Spigot Bands WAT 1402 Typical Steel Pipe Jointing Welded Pipe Collars WAT 1403 Typical Steel Fabrication Bends WAT 1404 Typical Steel Fabrication Access Opening for Pipes DN 750 WAT 1405 Typical Steel Fabrication Dismantling and Flexible Joints WAT WAT WAT Typical Steel Fabrication DI Installation Joint Corrosion Protection FABRICATION DETAILS continued alve Connection & Bypass alve Bypass Arrangement DI and GRP Pipe Cement Mortar Lined Steel Pipe DN 300 to DN 1200 WAT 1409 ydrant Installation Fittings PE Assemblies PE Code Page 4 of 17

5 WAT Typical Steel Pipe Jointing Welding of Existing Lead and Rubber Ring Joints W 27 Commentary on WAT-1100 Series Pipeline Layout W 27.1 General NOTE: 1999 Drawing WAT 212 Swabbing Point Typical Arrangement has been deleted from the new series of drawings * This Drawing is NOT used by unter Water. The 1100 series of Drawings deals with the layout and placement of mains and property services. AS 1100 Part , which specifies standard drawing symbols for water supply, has not been adopted by WSAA. A consensus standard is yet to be developed. Water Agencies should specify their individual requirements. W 27.2 WAT-1100 and WAT-1101 Design Layouts Delete clause WAT 1100 and WAT 1101 are not used by unter Water, see WAT and WAT 1152-, refer Clause W These two drawings are typical of drawings that need to be included in any set of Design Drawings in order to provide information necessary for the Constructor to construct and install the Works. W WAT-1100 Typical locality plan Delete clause WAT 1100 is not used by unter Water, see WAT WAT 1100 is a typical locality plan that forms part of the Design Drawings and shows details of the overall project and other general information required for the project. The locality plan should be at a minimum scale of 1:2500 and should provide an overall concept of the full project and identify any breakdown of the site as it relates to the site plan drawing(s). W WAT-1101 Typical site plan Delete clause WAT 1101 is not used by unter Water, see WAT WAT 1101 is a typical site plan that forms part of the Design Drawings. It shows details of the development layout and provides information necessary to complete the project (or part of the project). The Site Plan should be at a minimum scale of 1:1000 and should identify critical information necessary for installation of the mains and services. Individual Water Agencies may have alternative format requirements that take precedence over this drawing. W 27.3 WAT-1102-, WAT-1103-, WAT and WAT Typical Mains Construction These four drawings illustrate important features of transfer, distribution and reticulation mains. Reticulation mains are generally DN 375 and are tapped to provide property service connections. Property service connections may be installed during construction of the reticulation main using pre-tapped connectors. Alternatively, tapping and installation of the connection pipework may be undertaken after the main is pressurised. NOTE: The Water Agency s requirements for dry or under-pressure tapping should be outlined in the Specification. Transfer and distribution mains are generally not tapped. While there is no size limitation on mains classified as transfer or distribution, they are typically DN 300. Page 5 of 17

6 W WAT Reticulation main arrangements WAT shows typical layouts for DI, PC and PE reticulation mains. Installing property service pipes at the time of construction using pre-tapped connectors is considered best practice and is the preferred option of many Water Agencies for DN 100 and DN 150 PC and DI mains. W WAT Distribution and transfer mains WAT shows typical layouts for DI, PC, GRP and steel distribution mains. Thrust blocks are not required for steel mains that have welded joints. W WAT DN 63 PE cul-de-sac arrangement WAT shows typical layouts for PE mains in cul-de-sacs where a conventional continuous (loop) main would be uneconomical. igher rates of flow through a reduced size main (DN 63) reduce the potential for deterioration of water quality. Fire services should not be installed on DN 63 mains. For this reason, the length and placement of the larger diameter ( DN 100) feeder main should be extended to ensure the serviced houses can all be reached by fire hoses attached to the nearest hydrant. The water main from the isolation valve (as shown on the drawing) may be extended to achieve this requirement. The flushing point valve should have the handle removed or locked or otherwise secured to prevent illegal use of water. W WAT Connection to existing mains W 27.4 WAT and WAT Property Services Mainto-Meter WAT shows typical methods of connecting a new main to an existing main. For DN 63 PE connected directly to larger mains, Water Agencies may specify installation of a Fl-Fl isolating valve (gate, ball or butterfly) upstream of the PE stub flange. These two drawings show typical service connection details where single or split services are provided to individual premises. Such services are now predominantly installed using PE pipe because of water quality considerations and PE s flexibility, inert properties and ease of connection. They can also be installed using copper pipe. Copper pipe should be electrically insulated when connected to ductile iron to avoid galvanic corrosion of the ductile iron. Existing properties in some areas with older reticulation systems have electrical earthing systems that make use of the metallic water service line as the main earthing conductor. In some cases the metallic water main can form part of the electrical earthing system. Removal of the earthing conductor by replacement of either the main or services with a non-conducting material can render the electrical earthing unsafe. Appropriate safety precautions should be adopted. Where a metallic water main is to be replaced with a plastic main, a licensed electrician should make an assessment of potentially affected property earthing systems. Work should not commence until the electrician declares in writing that it is safe to proceed. Some Water Agencies require an encasing pipe to be laid across the road where th e property service passes under vehicular traffic areas. Where applicable, this requirement should be included in the Design Drawings. The location of the property connection point, meter riser and its orientation should be in accordance with Water Agency requirements and details should be included in the Design Drawings. Page 6 of 17

7 Industry practice is generally to hand dig to locate underground services prior to machine digging. One recent innovation is vacuum potholing, which is proving a more efficient means of locating buried pipes, particularly in congested pipe corridors. The alternative layout shown for split water services with bifurcation tee located within the property shall only be used when locating the tee within the footway is not practical due to congestion of existing services. Obtain unter Water approval prior to using this alternative. The preferred location for split water services is the alternate side property boundary to the electrical and Telco services (i.e. at one side boundary have Telco, electrical supply pillar box and lights and at next side boundary have split water service. Designers to negotiate with other service providers to clarify locations. W 27.5 WAT Property Services Connection to Main arious modifications for unter Water requirements. WAT shows typical details for connecting a property service to a (reticulation) main. Pre-tapped connectors are the preferred option for all connections installed during construction of the reticulation main because they are an integral part of the pipeline s ystem rather than an add-on component. Pre-tapped connectors reduce the likelihood of leakage, external corrosion of DI mains and external damage to PC mains. Tapping bands used on PC pipe should be full circle clamping to prevent over tightening and subsequent compression of the pipe. Electrofusion welded tapping saddles should be used at all times with new installations of PE pipe. Tapping of curved PE pipe should take place only at the top of the pipe to minimise stress around the tapping hole. Where dry tapping is performed, a plug cutter should be used, and all swarf removed. Under pressure tapping should be used only with systems that utilise plug cutters that retain the PE pipe wall plug within the cutter. Where welded tapping systems are used, the assembly should be allowed to fully cool naturally before cutting the mainline PE plug. W 27.6 WAT Property Services Above Ground Meter Assembly Arrangement WAT shows typical arrangements for a meter connection. Individual Water Agencies have different requirements for installation, which should be confirmed prior to commencing construction. The lay-over arrangement is used to prevent illegal water use or vandalism / wastage and should only be carried out when specified by the Water Agency. The Designer is responsible for identifying the requirement and highlighting the requirement in the Design Drawings. unter Water requires that the lay-over arrangement be used unless notified otherwise. W 27.7 WAT Water Main Symbols WAT shows symbols to be used in concept plans and detailed Design Drawings. W 27.8 WAT and WAT These two drawings are typical of drawings that need to be included in any set of Design Drawings in order to provide information necessary for the Constructor to construct and install the Works. W WAT Typical locality plan WAT is a typical locality plan that forms part of the Design Drawings and shows details of the overall project and other general information required for the project. Page 7 of 17

8 The locality plan should be at a minimum scale of 1:5000 and should provide an overall concept of the full project and identify the site and any breakdown of the site as it relates to the site p lan drawing(s). For smaller developments, the locality plan may be included on the Site Plan. W WAT Typical site plan WAT is a typical site plan that forms part of the Design Drawings. It shows details of the development layout and provides information necessary to complete the project (or part of the project). For larger developments, several site plans may be required. The Site Plan(s) should be at a minimum scale of 1:1000 and should provide all information necessary for installation of the mains and services. Individual Water Agencies may have alternative format requirements that take precedence over this drawing. W 27.9 WAT Design Layouts Utility Services Space Allocations in Footways unter Water Area W 28 Commentary on WAT-1200 Series Drawings Embedment, Trench Fill and Restraints W 28.1 General WAT shows utility services space allocations in footways as currently adopted by local councils within unter Water s area of operations. The 1200 series of drawings deals with identifying the appropriate embedment and trench fill for particular locations and the method of installation of water mains, including those in difficult soil conditions. It is the Designer s responsibility to make every effort to identify potential problems and provide appropriate solutions. Although the arrangements shown in these drawings are deemed to comply solutions, the Designer is required to nominate relevant details for a specified project. Engineering advice based on geotechnical information from site may require alternative methods, which should be detailed in the Design Drawings and/or Specification. The trench widths shown in the drawings are consistent with criteria specified in AS/NZS The trench depths are based on theoretical requirements for pipe support and minimum cover and may not take into account physical construction requirements or potential damage to the main resulting from loadings imposed during construction prior to full cover being achieved. Table 28.1 provides general guidance for Designers and Constructors on minimum trench dimensions. Road authorities may require additional cover in roadways. Trench details applicable to unter Water are shown in Drawings WAT and WAT Pipe 1 size DN Nomina lod mm Maximum valve height 2, 3 mm TABLE 28.1 MINIMUM TRENC DIMENSIONS Lc min mm Informative Lb min mm Minimu m trench width mm Minimum trench depth Nonroadwa y Commerci al 2, 3, 4, 5, 6, Roadway a embankme Page 8 of 17

9 NOTES: 1 For flexible pipes (PC, DI, GRP, PE and steel) having initial ring bending stiffness N/m.m. 2 eight of valve assumed to be (Refer AS and AS ). 3 Maximum cover for mains DN 375 = 1.2 m and >DN 375 = 1.5 m. 4 Minimum cover to top of main should be as shown on WAT Clearance to top of valves should be as shown on WAT 1301-, WAT-1302-, WAT and WAT Water Agencies may authorise reduced trench depth with localised increased depth to enable valves to achieve the minimum cover to top of valve spindle of 100 mm. 7 Type B embedment is considered the normal situation and is assumed to apply. 8 alve size can be reduced one pipe size for mains DN 500. Special embedment includes those shown in the Standard Drawings and is typically specified where any portion of the pipe embedment zone is below the natural water table or in unstable ground conditions. Except where water mains are being embedded in single size aggregates, satisfactory compaction of embedment and trench fill usually requires the use of powered portable compacting machines. In certain circumstances manual methods of compaction are suitable. Compaction lift thickness should not exceed 150 mm for hand tampers and 300 mm for vibrators. Compaction can be achieved using hand tampers, surface plate vibrators, vibratory rollers and/or internal vibrators. Where the compactive force and bearing area of the compaction / construction equipment is known, design in accordance with AS/NZS can be used to determine the minimum height of cover before that load can be applied. Fill material requirements will depend upon dead and live loadings and the maximum allowable settlement of the fill material. Where the surface is not to be paved and surface sett lement is not important, native fill material above the embedment material is suitable up to the finished surface. The minimum densities specified for side support and overlay fill in non-trafficable areas are the minimum densities required to ensure that they do not settle under trench fill loading and saturation. Any embedment fill that settles around a flexible pipe would not provide the lateral support to the pipe assumed in the design method for flexible pipes, even if its laboratory measured modulus was apparently sufficient. Note that modulus is determined in the laboratory using an oscillating dynamic load and extremely low strains. Even a reasonably high modulus from this test is no guarantee that the material will not settle or even collapse under its own weight. The compaction requirements specified in Clauses 16.3, and 17.2 are to ensure pipe structural support and to prevent settlement that may cause damage to pavements and structures. Settlement at any depth in a trench is ultimately likely to be reflected at the surface. Page 9 of 17

10 Flood compaction is only suitable for free draining soils. If used where soil is not free draining, the retained moisture makes compaction, even mechanical compaction, very difficult, if not impossible. W 28.2 WAT-1200 Soil Classification Guidelines WAT 1200 provides guidance to Constructors on the estimation of the allowable horizontal bearing pressure of soils. The results enable Constructors to confirm the thrust block and anchor block requirements and ensure that the embedment method shown in the design drawings is suitable. W 28.3 WAT Embedment and Trench Fill WAT shows the typical arrangement for embedment and trench fill. It also identifies the terminology used for the key support areas that are discussed in the design and construction sections of the Code. Embedment and compaction requirements are detailed in Clauses 16 and 17and are not shown on these drawings. Requirements should be as specified. Correct haunch support (shown on drawing) is the key to providing adequate support for flexible buried pipes. Before compacting, it is important to manually work the embedment material into the haunches to ensure all voids are filled. Trench fill comprises the material installed above the embedment zone up to the finished surface level, as shown in the Standard Drawings. Councils and/or Road authorities may require greater cover than the minimum pipe cover shown on this drawing. W 28.4 WAT-1202 Standard Embedment All Pipe Types W 28.5 WAT-1203 Special Embedments Inadequate and Poor Foundation WAT 1202 shows the standard deemed-to-comply embedment for good supportive soil conditions. Type B embedment should apply in all standard situations except where the main is being laid in clean fine sand, where Type A may be used. WAT 1203 complements WAT and Sections 5 and 14 of the Code. The drawing shows typical embedment where there is inadequate / poor foundation. Specialist geotechnical advice is required to determine the appropriate embedment for a particular situation and, where piling is required, to specify spacings and structural details. W 28.6 WAT Special Embedments Concrete, Geotextile and Cement Stabilised Systems Concrete encasement detail added. WAT complements WAT 1203 and Sections 5 and 14 of the Code and shows the deemed-to-comply embedment for particular situations. The concrete encasement systems (Types J and K) are typically used for maintenance-free or highly loaded situations such as major road crossings. The cement-stabilised fill system (Type L) is typically used where structural support and/or avoidance of surface settlement is required (such as for mains installed in a minor road). The lean stabilised embedment material used can be excavated by standard methods to gain access to the main for maintenance. The geotextile filter fabric surround system is generally required where coarse granular embedment is used in a native soil that contains fines. The geotextile filter fabric prevents groundwater washing fines from the native soil into the embedment with consequential l oss of Page 10 of 17

11 structural support of the main. Specialist geotechnical advice may be required to indicate when this system is required. W 28.7 WAT-1205 Thrust Block Details Concrete Blocks W 28.8 WAT-1206 Thrust Block Details Timber & Recycled Plastic Blocks Delete WAT-1205 and insert WAT Delete clause WAT 1205 shows the deemed-to-comply thrust block arrangement for a network with a test pressure of 1000 kpa (DP = 800 kpa). The nominated areas can be used for all pressures up to the stated value. For systems over this pressure, a new thrust block area ca n be determined by extrapolating the areas on the basis of pressure ratios. Before constructing thrust blocks, the bearing capacity of the soil should be determined / checked by the Constructor using the method shown in WAT Note: WAT 1206 not used by unter Water. WAT 1206 shows details of timber and recycled plastic thrust blocks. Some Water Agencies do not allow the use of this system for permanent restraints, but may allow them to be used as temporary restraints. W 28.9 WAT Thrust and Anchor Blocks Gate alves and ertical Bends WAT shows details of thrust blocks for valves and vertical bends. Although very few incidents of main / valve movement have been reported, there is the potential for a serious accident to occur in the event that a valve is dislodged under pressure during operation and maintenance activities e.g. a cut-in into the main adjacent to and downstream of the valve. The Designer should consult the Water Agency to determine current requirements and show details in the Design Drawings. It is recommended that all valves DN 250 be restrained in accordance with WAT unter Water requires that all valves are to be restrained in accordance with WAT Anchor blocks, as shown, are required for vertical bends that do not have restrained joints. For larger diameter mains, consideration should be give to the use of flanged or welded connections in lieu of anchors. W WAT-1208 Restrained Joint System DN 100 to DN 375 DI Mains WAT 1208 covers the rubber ring locking method of mechanical restraint for DI pipe e.g. Tyton- Lok. The distances shown are the minimum buried lengths of straight pipe with restrained joints, either side of a bend / tee or other fitting, to ensure there is no movement of the pipe or fitting. All restrained joints and the associated lengths of pipework should be marked with pink marking tape to ensure no cut-ins are made without the appropriate pipe restraint being provided. unter Water allows the use of restrained joints in special circumstances when there is no other feasible alternative. Obtain unter Water approval prior to using restrained joints. Do not use restrained joints on PN20 DI pipe. W WAT-1209 Trench Drainage Bulkheads and Trenchstop 2 nd paragraph delete Table 5.1 and insert Table 7.5 WAT 1209 shows deemed-to-comply bulkheads and trenchstops that are used on steep slopes primarily to slow any groundwater flowing through the embedment. Unregulated flows have the potential to wash away pipe support material. Details of when bulkheads / trenchstops are to be used should be shown in the Design Drawings. Details can be determined from Table 5.1. Page 11 of 17

12 The compressible membrane around the main has the secondary effect of restraining lateral main movement. W WAT-1210 Trench Drainage Typical Systems WAT 1210 shows deemed-to-comply groundwater discharge systems, primarily for bulkheads and trenchstops, but which can be used also in other areas where ground water needs to be drained from a trench. The Drawing also shows typical drainage systems, including placement of drainage pipes within (along) the trench for use where suitable groundwater discharge points are unavailable. W WAT-1211-, WAT-1212-, WAT and WAT Buried Crossings W WAT and WAT Standard Trench Details WAT Pipe end treatment in encasement modified. WAT and WAT Pipe end treatment in encasement modified. Grouting and concrete encasement of ends required for mains in bored encasing pipes. These four drawings show deemed-to-comply methods of passing pipes under major obstructions. The drawings show letters representing lengths specific values should be detailed in the Design Drawings. The road / railway Owner may dictate trench fill and compaction requirements for water mains laid under major roadways and railways. Concrete encasement has been the principal method of protecting pipework in the past, but directionally bored PE pipe is now a viable alternative. Consideration should be given to maintenance reduction and access requirements for all installations e.g. corrosion protection system, pump-out points, grading to prevent settlement and improve flow and access points for pigging. Companies that specialise in boring and tunnelling are now available and should be consulted to determine the easiest and most economical method of achieving the required outcome. For more information visit WAT and WAT are deemed to comply Design Drawings for installation of water mains in stable ground. W WAT Thrust Block Details W WAT and WAT Anchorage Details Stop alve Installations Delete WAT-1205 and insert WAT WAT addresses the design of thrust blocks for larger size mains (i.e. DN 450 DN 750) than WAT 1205 which is limited to mains DN 375. Detail design is required for specific projects. WAT and WAT complement WAT (which is limited to mains DN 375) and address design of anchorage of large stop valves in steel mains and DICL mains respectively). Detail design is required for specific projects. W WAT Buried Crossings WAT complements WAT 1211-, WAT 1212-, WAT and WAT and addresses the design of crossings under minor obstructions. W 29 Commentary on WAT-1300 Series Installation Practices/Structures W 29.1 General The 1300 series of drawings deals with installation practices for pipework and associated ancillary equipment. It is the Constructors responsibility to know and understand these installation practices and to ensure the appropriate pipes, fittings and ancillary equipment are available prior to commencing Page 12 of 17

13 the project. Where irregularities are identified they should be discussed with the Designer or Superintendent. Details and location of variations to the installed pipework should be recorded in the Design Drawing and returned to the Water Agency as part of the As Constructed inf ormation. W 29.2 WAT alve and ydrant Identification WAT shows deemed-to-comply identification and marker post systems. Water Agencies may have varying standard systems and these should be determined prior to commencing the project. W 29.3 WAT and WAT Typical alve & ydrant Installation WAT and WAT arious modifications for unter Water requirements. These two drawings show typical arrangements for installing stop valves, hydrants and air valves. Pipe connections should be flanged or rubber ring jointed (RRJ). All uncoated and bitumen coated pipe and fittings should be protected by a petrolatum tape or PE sleeving system, especially the flanges and bolts. WAT 1313 shows corrosion protection details for bolting. A shroud or sleeve should be provided at each valve or hydrant to prevent the trench fill affecting the operating parts. The sleeve or shroud should be a minimum size of DN 225. Plastic identification covers should be used on valve spindles where specified by the Water Agency. The specified clearance between the valve spindle cap or hydrant claw and the finished surface level should be within the tolerances shown. ariations to these clearances may result in operational problems. unter Water prefers N55 type vent or similar located adjacent to fence. W 29.4 WAT-1303-, WAT-1304-, WAT and WAT Typical Surface Fitting Installation Modified to show unter Water requirements. These four drawings show typical arrangements for installing trafficable (Class D, heavy duty) and non-trafficable (Class B, light duty) valve and hydrant covers. The covers shown are a selection of those used in Australia and should be considered as indicative only. WSAA is working with manufacturers to standardise on a range of covers and frames. Each Water Agency has an authorised range of covers and frames and a range of associated support material. Each cover shown has been given a type letter to allow easy identification. Prior to commencing projects, the appropriate covers and associated materials should be obtained and the correct method of installation determined. These drawings show an asphalt premix seal underneath each shroud to prevent the ingress of dirt and water. This is optional and may be omitted where it is not a requirement of the Water Agency. W 29.5 WAT Typical Appurtenance (Scour) Installation WAT shows various deemed-to-comply scour arrangements. The Designer should identify the need for a scour and determine the appropriate take-off point. The scour should be located adjacent to an approved discharge point and the Design Drawings should detail the connecting pipework and the shape and size of any collection structure required. Page 13 of 17

14 A second isolating valve may be required adjacent to the collection structure to allow the scour pipework to be isolated. W 29.6 WAT and WAT Typical Appurtenance (alve) Installation WAT table showing bypass requirements modified. Reduced size chambers to WAT or WAT are normally allowed by unter Water for water mains up to DN 750. Full size chamber to WAT may be required in some situations. These two drawings show deemed-to-comply valve chamber arrangements. Other arrangements may be used provided they incorporate the following conditions / features: (a) (b) (c) (d) (e) (f) (g) Pipework to be restrained using thrust rings cast into chamber wall or similar. Dismantling joint to be included in internal pipework. All pipework to be supported. Suitable access facilities to be provided, including ladders. O&S requirements to be addressed for crossing over pipes for maintenance purposes. Chamber to be covered with solid cover or open grid walkway to prevent falls. A floor drain or pump and sump to be provided. Internal and external formwork should be locked together during pouring and vibration. It may also require other restraint to prevent movement. alves with built-in bypass systems (sizes DN 450 to DN 600) are commercially available. These valves may offer a lower cost option and may be used in buried applications. W 29.7 WAT-1310-, WAT-1311 and WAT Aerial Crossings These three drawings show deemed-to-comply methods of aerial crossings of depressions or waterways. Other arrangements may be used provided they incorporate the following conditions / features: (a) (b) (c) (d) (e) (f) For supported / suspended systems, the pipe material to be DI, steel or GRP. Pipe to be supported at spacings as recommended by the manufacturer. Allowance to be made in the design for 1 in 100 year flood conditions. Provision to be made for pipe expansion and contraction. Provision to be made to prevent unauthorised access onto main. Consideration to be given to corrosion protection of the main. The DI or steel pipe may also be an encasing pipe with PC or PE pipe used as the water main. The Design Drawings should detail all requirements including pipe material, jointing method, support spacings, expansion control methods, corrosion protection and abutme nt details. W 29.8 WAT-1313 Flanged Joints WAT 1313 shows deemed-to-comply methods of bolting flanged joints. Bolted joint systems need careful consideration. Because of potential corrosion problems, precautions must be made to prevent contact between dissimilar metals. The three bolting systems for flanges in common use are as follows: (a) Buried ductile iron flanges with galvanised (or black) bolts, nuts and washers: Page 14 of 17

15 (i) (ii) This system must be protected as detailed in Note 4 on the drawing. This system was common, but, with the introduction of fusion bonded polymeric coatings on valves and fittings and the use of SS bolts, this system is being used less frequently. (b) Fusion-bonded coated DI valves and fittings and non-metallic flanges used with grade 316 SS bolts, nuts and washers: (i) (ii) This system requires no protective coating providing the flange coating extends into the holes to electrically isolate the SS bolts from the DI. All PC and/or PE flanges require grade 316 SS backing flanges. (c) Mixed metallic (steel and DI) flanges with galvanised (or black) bolts, nuts and washers: (i) (ii) This system requires insulated joints that mechanically isolate the dissimilar metals. This system must be protected as detailed in Note 4 of the drawing. Cathodic protection (CP) requires flanges to be insulated using the method shown (or similar). Details of where steel flanges need insulation should be shown in the Design Drawings. Petrolatum tape wrapping (see DI flanges with galvanised bolts figure) should be used in all cases. Washers should be used on all bolted joints under both bolt heads and nuts. W 29.9 WAT and WAT Typical Appurtenance (alve) Installation 1 st paragraph delete Clause and insert Clause WAT and WAT show chamber installations that enclose only the gearbox of a large valve and bypass in a footway and carriageway respectively. The drawings are referenced by Clause as alternatives to WAT Designers are to confirm availability of fittings. alves with built-in bypass systems (sizes DN 450 to DN 600) are commercially available. These valves may offer a lower cost option and may be used in buried applications. W WAT Aerial Crossings Circular RC Piers in Non- Flood Conditions WAT shows typical deemed-to-comply circular RC piers in non-flood conditions for DN 100 to DN 750 water mains. W 30 Commentary on WAT-1400 Series Fabrication Details 30.1 General 1 st paragraph delete Clauses 4.13 and and insert Clauses 4.6 and The 1400 series of drawings deals with fabrication practices and are considered deemed -tocomply solutions. Other variations are also acceptable, but the proposed method should be authorised by the Water Agency before use. Welding requirements are specified in Clauses 4.13 and The practices outlined in these drawings are applicable to new pipeline systems. Different methods may be applicable to maintenance applications. Steel pipes and fittings designed and manufactured in accordance with AS 1579 can be supplied in a variety of sizes and thicknesses and should be selected in conjunction with the manufacturer s recommendations. Only certified welders should carry out in-situ welding of steel pipes and fittings in accordance with pre-qualified weld procedures. Where SCL pipe is to be used in conjunction with wafer type butterfly valves and non -return valves, it should be verified that the disc will not foul on the internal li ning. Page 15 of 17

16 Rubber lined butterfly valves depend on the flange clamping force to retain the lininleg in the valve body. Experience has shown that size-on-size SCL pipe is not sufficient for this purpose because the cement lining will not maintain the required force. One method to overcome this is to insert a full size steel flange between the pipework and the valve to maintain the required interface pressure. Two methods for setting up valve bypass systems are shown in these drawings, but some manufacturers are now producing gate valves with built-in bypasses. This may provide the lowest life-cycle cost. W 30.2 WAT-1400 Typical Steel Pipe Jointing Butt Welding of Joints Delete O&S and insert WS WAT 1400 shows pre-qualified butt weld joint details. One-sided welding is required where person-entry is not physically possible or where prevented for O&S reasons, typically for pipes of size <DN750. W 30.3 WAT Typical Steel Pipe Jointing RRJ Spigot Bands Table showing steel pipe ODs modified. WAT shows requirements for the provision of spigot bands used to adjust the OD of the steel pipe at the rubber ring seal joint the steel main is to be connected to a socketed pipe, valve or fitting. The OD of the spigot must form a leak tight joint. W 30.4 WAT-1402 Typical Steel Pipe Jointing Welded Pipe Collars W 30.5 WAT-1403 Typical Steel Fabrication Bends WAT 1402 shows requirements for the plain-ended, butt-welded collar joint system. Bends manufactured to Water Agency approved manufacturers standard designs may be acceptable. WAT 1403 shows requirements for the fabrication of bends. The fabricated bends shown indicate the minimum practicable dimensions for this type of flanged fitting. Their dimensions are not in accordance with the typical bend configurations of AS A range of configurations is available and all fittings should be manufactured to Water Agency requirements. W 30.6 WAT-1404 Typical Steel Fabrication Access Openings W 30.7 WAT-1405 Typical Steel Fabrication Dismantling and Flexible Joints WAT 1404 shows a typical access M for steel pipe. Requirements and locations should be shown on Design Drawings. WAT 1405 shows a typical fabrication detail for dismantling and flexible joints. A range of dismantling joints and connectors are commercially available. owever, joints may be fabricated as shown in the Design Drawings. W 30.8 WAT and WAT alve Connection & By-Pass Arrangements WAT Typical fittings arrangement and notes modified to cater for anchorage requirements. These two drawings show typical valve connection and bypass arrangements for steel, DI and GRP mains. Page 16 of 17