Engineering Technical Guidance Notes

of 29 Once printed this document becomes uncontrolled. Refer to electronic copy for controlled copy.

Engineering Technical Guidance Notes

Revision Prepared By Date Original Doc 2004 Rev 3 Principal Engineer 2017-June Rev 4 Principal Engineer 2018 -April

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Once printed this document becomes uncontrolled. Refer to electronic copy for controlled copy.

Contents 1. Scope

2. Public Safety

3. Footpath/Crossover Concrete

3.1 Excavation

3.2 Plans and Survey

4. Loads on minor concrete structures

5. Backfill

6. Services, Public Utilities Etc

7. Compaction

8. City or Private Property

9. Alignment and Profile –Crossover

10. Construction- Crossover/Footpath

11. Kerb

12. Tolerances

13. Roads

14. Cycle Path

15. Strom Water Drainage

16. City of Fremantle - Guidelines for better management of Urban

Stormwater for Commercial Properties

17. Guidelines for better management of Urban Stormwater for Residential

Properties

18. Reinstatement of Flexible Pavement

19. On Street Parking Dimensions

20. Appendix

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1. Scope

This is Technical Notes for footpath, road, drainage, kerb and block/brick paving construction and reinstatement of the road and footpath within the City of Fremantle Local Government Area and a guide to the Detailed Design and Maintenance of the City’s Road Infrastructures. 2. Public Safety The Contractor shall be responsible for Public Safety including pedestrian and vehicular in accordance with Australian Standard AS 1742.3, the City's Traffic Management Procedure for road reserve and the Disability Discrimination Act. Alternative routes shall be signed for pedestrians around the works. All bunting and flashing bollards shall be installed around the works and maintained until the paths are reopened to the public. 3. Footpath / crossover

3.1 Excavation

The subgrade shall be formed at the required depth below the finished surface levels. Rock foundations shall be neatly excavated to form a bed for the concrete, and shall be thoroughly scraped and cleaned. Soil foundation shall be excavated neatly from the solid material to coincide with the under- surface of the subbase material as far as possible. All soft, yielding or other unsuitable material shall be replaced with sound material approved by the City's Engineer and the subgrade shall be compacted to provide a minimum relative compaction of 95 per cent as determined by AS 1289.5.4.1 for standard compactive effort. If the subgrade is dry it shall be sprinkled with as much water as it will absorb, before the concrete is placed.

3.2 Plans and Survey The Contractor shall be responsible for setting out the footpaths accurately to line and level in accordance with the instruction supplied and arrangements must be made with the Developer or City to have the setting out checked prior to the work commencing. All soil including old concrete paths shall be removed from the site and the area kept neat and tidy to ensure minimum obstruction to traffic ways during the course of the work. No stockpiling of excavations shall be left on verges. All footpaths shall have 2% fall from property boundary to top of the kerb (ie 30mm crossfall for 1.5 m wide footpath).

• Dimensions Sub Base for Footpath: The subgrade is to be covered with 100 mm of fine crushed lime stone and material shall be thoroughly compacted by rolling.

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• Limestone for Footpath Crushed limestone shall be obtained and crushed to comply with IPWEA Local Government Guidelines for Subdivisional Development Edition 2.2 – 2012 Crushed Limestone.

• General The limestone shall be free from sand, loam, capstone, roots and other foreign material and shall not contain either oversize spalls or an excessive proportion of fine grained material.

• Footpath A minimum thickness of 100mm of concrete is required for all paths unless otherwise specified .The concrete footpaths shall be minimum of 1.5m wide located parallel to existing kerb lines and shall be constructed accurately true to line and level within a tolerance of plus or minus 5 mm. At street corners the path shall be extended to the kerbing and comply with Disabled Ramps. Formwork shall be of such cross-section, strength and secured as to resist the pressure of the concrete. When placed, the impact and vibration of any equipment which they support without springing or settlement. The method of connection between sections shall be such that the joints shall not move in any direction. The maximum deviation of top surface of the form shall not exceed 10mm in, 3m or the inside face not more than 10mm in 3m longitudinally. Formwork may be of either steel or planed timber and shall be fixed so as not to flex or displace during concreting operations. Formwork shall be of dimensions equal in depth to the thickness of the concrete to be poured.

• Setting Formwork The formwork, when set, will be uniformly supported for its entire length at the specified elevation. The supply of formwork materials shall be sufficient to permit remaining in place for at least twelve (12) hours after the concrete has been placed / laid.

• Joints Joints shall be provided at intervals of no more than 1.5m along the length of the footpath and either side of driveways. Contraction joints will be installed where there is an existing concrete footpath. The joints are to be 2.0m apart or as per the existing footpath. Lock joints are to be installed in all new footpaths with spacing’s at 4.0m intervals and every fifth being an expansion joint using Canite, Abbelflex or other such products. Approved expansion joints shall be provided at not more than 10m intervals along the footpath. These joints shall be 10 mm wide and for the full depth of the concrete pavement shall be filled with an approved expansion jointing material such as bitumen or other flexible material such as plastic or bitumen impregnated fibre, refer to standard footpath details.

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• Concrete Ready mixed concrete conforming to relevant Australian Standards and to the standards outlined in this specification shall be used for this work. Concrete shall have a minimum 28 day strength of 25 MPa and have a slump of 75 mm. Maximum aggregated size shall be 20mm. Sand shall be clean, sharp, washed river or quarry sand, free from silt and organic matter. Tests of concrete will be taken at locations and intervals of time at the discretion of the City. Materials not satisfactory shall be removed and shall be replaced by the Contractor at the contractors cost. The sub-grade and subbase shall be moistened immediately prior to the placing of concrete. No concrete pouring shall take place during rain, or when the shade temperature exceeds 38°C. All concrete is to be thoroughly consolidated. A broom finish (approximately 2 mm deep) and broomed in a transverse direction are required across the footpath slabs, or an exposed aggregate finish approved by City. All joints and edges are to be finished with an edging tool. The surface of the concrete shall be kept damp for 7 days and / or the surface shall be sealed by using curing oils or sealing compounds submitted and approved by and on the City’s direction. All exposed surfaces of the finished slabs shall be covered with thick opaque polythene or other approved sheeting, for a period of at least 24 hours to avoid damage by rain or too rapid drying in the heat. Adequate protection shall be given to the work until cured. The contractor shall be responsible for replacing any damaged or defective concrete work due to any cause whatsoever including graffiti in the period of one week following the pouring of the concrete. The edges of the paths shall be trimmed of excessive concrete to form a clean vertical edge. Note: A steel trowel finish is not permitted on any surface of a footpath.

4 Alignment and Profile –Crossover

a) All crossovers shall be at right angles (90 degrees) to the carriageway kerb

lines unless approved otherwise by the engineer, Infrastructure Engineering Unit, City of Fremantle.

b) Where internal driveways have been installed, the crossover level shall be within 5mm of the level of the internal driveway height at the property line.

c) There shall be a 2% crossfall away from the property boundary for a minimum distance of 1.2m. This constitutes the width of a footpath at the property line.

d) If height at property boundary is greater than 400mm or below road channel level, the crossover must be constructed with a series of grade changes.

e) No crossover shall be constructed closer than 12m to the property alignment of another road intersecting with the carriageway that the driveway services, nor shall It infringe upon any part of a corner truncation of 6.0m unless otherwise approved by the engineer, Infrastructure Engineering unit ,City of Fremantle.

f) No crossover shall be constructed closer than 3.0m from a verge tree unless otherwise approved by the Parks unit, City of Fremantle.

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5 Compaction Crossover All excavation shall be thoroughly compacted to produce a Perth penetrometer reading of minimum seven (7) blows per 300mm. 6. Loads on minor concrete structures No superimposed load shall be allowed on any part of what will become a load bearing structure within 21 days after placing concrete unless the structure is effectively and independently supported to the satisfaction of the structural engineer or when the Contractor can demonstrate that 95 per cent of the design strength of the concrete has been achieved. 7. Backfill The space behind the footpath and between the footpath and kerbing where applicable, shall be backfilled relevelled and raked smooth with approved material and lightly compacted to the approved grades and levels not sooner than 7 days after placing the concrete. 8. Services, Public Utilities etc. No work is to commence before service authorities have been notified and services have been located. The contractor is responsible for all service locations and associated costs. The Contractor shall make all arrangements with the appropriate authorities ( ie Western Power, Water Corp, AtcoGas and Telecommunication authorities) for the relocation or alteration of any public utility service inspection opening, etc. which may be necessary for the completion of the work. Inspection openings shall be adjusted to the level of the finished footpath. The Contractor shall be responsible for any damage done to public utility services, inspection openings, etc. sustained as a result of the works. 9. City or Private Property

a) The Contractor shall be responsible for any damage caused to City or private property or laneways adjacent to the works. The City may repair any city infrastructure damaged by the contractor and recover the associated costs from the Contractor.

10. Construction Concrete

a) The works shall consist of 100mm for residential and 150mm for commercial,

thickcast insitu premixed concrete constructed on a prepared subgrade in accordance with this Specification and in close conformity with the lines, grades, thickness and typical cross-sections shown on the drawing.

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b) All concrete used in works shall develop a minimum compressive strength of 20 MPa for residential/ and 25 MPa for commercial at 28 days and comply with AS 3600. Slump at the point of delivery shall be 75mm. Maximum allowable aggregate size for crossovers is 20mm.No admixtures shall be used in the concrete unless specifically approved. If required high early strength additive shall be used to give rapid hardening as per AS1478 and AS1479, Chemical Admixtures for Concrete.

Brick Paving Sand bedding shall be spread loosely to a uniform depth and screeded to the nominated design profile with sufficient surcharge to allow for compaction to a uniform thickness of 30 mm, with a tolerance of ±5 mm. Laying Segmental Paving Blocks

a) Paver shall be laid on uncompacted bedding sand and shall be placed so that

Units are not in direct contact with each other. b) Pavers shall be laid with a 2 mm (minimum) to 3 mm (maximum) gap between

the pavers. This 2mm to 3mm gap is an essential feature of the interlocking pavement.

c) All rectangular interlocking pavers shall be laid in a 45 degrees herringbone configuration. Full pavers shall be laid first and gaps at the pavement edge shall be neatly filled by saw cutting pavers to fit. Only full bricks/blocks shall be laid against all edges restraints. (Minimum cut shall be 1/3 of the pavers size).

Segmental Paving Block Compaction

a) The pavers shall be compacted and brought to design level by not less than 3

passes of a vibrating plate compactor. Compaction shall continue until a smooth surface is produced. The top of the paving shall finish 5 mm to 8 mm above abutting drainage inlet structures. When compaction is completed gaps between pavers shall be filled with dry joint filling sand.

b) Pavements subject to stormwater runoff, gutter flow or any other movement of water shall be protected from scouring. Scour protection shall be provided by means of dry cement grouting of the paving joints for a width of 300 mm from the edges of interlocking pavements. The joint filling grout shall consist of a 4:1 mix of 1.18 mm sieve dry sand and dry cement.

c) Where damage to adjoining properties may result, the use of vibrating rollers will only be permitted with care and in negotiation with the City's representative to ensure all measures are taken to protect adjacent properties.

d) It may be necessary to formulate a vibration plan in conjunction with the City's noise management plan. Plan would need to address vibration, noise nuisance and potential damage and be approved by City's Environmental Health Officer.

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e) The driveway will achieve a smooth transition from the layback through the high point back the existing driveway or boundary to eliminate vehicle scraping or bottoming out. The finished alignment shall conform to requirements of the approved drawings and must not impede the flow of water or be detrimental to adjoining properties.

f) Variations of levels must be approved by the City's Infrastructure Engineering Unit representative. Where a foot path intersects a driveway the path section of the driveway will be constructed to foot path design and continues through the driveway.

Backfilling and Reinstatement of verge

Backfilling to the driveway shall be placed after pavement construction is complete. Backfill material shall be free draining sand or a similar material to the local topsoil, free from debris and compacted to a thickness not less than that of the surrounding natural surface.

11. Kerb:

Keyed Kerb Where keyed layback is specified on approved drawings, excavation of the base shall be by an approved method. The road surface beyond the line of the face of layback shall not be disturbed. Finish The completed pavement surface shall satisfy the following criteria prior to acceptance a) The complete pavement surface shall be constructed in accordance with design

profiles and shall drain freely; b) The pavers shall not be cracked, damaged or distorted; c) The surface texture shall be uniform and be free from abrasion or wear and the

colour of the pavement shall be uniform and any colour variations in batches of pavers shall be eliminated by batch mixing to produce a uniform colour grade.

Barrier or Semi-Mountable Kerbing Where semi-mountable kerbing is in place at the crossover entrance, the length of kerbing equal to the appropriate entrance width of the crossover shall be removed in all cases.

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Mountable Kerbing Where mountable kerbing is in place at the crossover entrance, the length of kerbing equal to the appropriate entrance width of the crossover shall be removed only if:

a) the mountable kerbing is cracked in one or more places; or b) the average depth between the road surface and the front edge of the

mountable kerbing exceeds 25mm, where the final hotmix surface has been placed, where kerbing is to be removed.

It shall be cut clean and removed carefully so as not to disturb the surface of the roadway.

Flush Kerbing Where flush kerbing is to be used which could carry loadings on a regular basis from traffic. The strength of the kerb should be to 32 MPa at 28 days with steel reinforced. Before placing any kerb, the foundation material shall be shaped and compacted to a firm base. Other than kerb constructed on pavement courses, the relative compaction shall be in accordance with the requirements of AS 2876. Where placed on pavement courses, the foundation shall be compacted to the requirements of the respective pavement course. The foundation material in all cases will be subject to Infrastructure Engineering Engineer’s approval. This action constitutes a HOLD POINT. The Engineer’s approval of the foundation material is required prior to the release of the hold point. Kerb-Construction

a) Kerb may be constructed in fixed forms, by extrusion or by slip forming in

accordance with AS 2876. b) The foundation, concrete quality, curing and testing details shall be in

accordance with AS 2876. c) The top and face of the finished kerb shall be true to line and the top surface

shall be of uniform width, free from humps, sags or other irregularities. d) When a straight edge 3m long is laid on top of or along the face of the kerb, the

surface shall not vary more than 5mm from the edge of the straight edge, except at kerb laybacks, grade changes or curves or at gully pits requiring gutter depression.

e) Unless shown otherwise on the Drawings, contraction joints, shall be formed every 3m length for a minimum of 50 per cent of cross sectional area. The joint shall be tooled 20mm in depth to form a neat groove of 5mm minimum width.

f) Unless shown otherwise on the Drawings, expansion joints, 15mm in width for the full depth of the kerb, shall be constructed at intervals not exceeding 15m and where the kerb abuts against pits, retaining walls, overbridges and at both sides of kerb.

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g) Expansion joints shall consist of a preformed jointing material of bituminous fibreboard or equivalent approved by the Engineer.

h) Where kerbs are cast adjacent with a concrete pavement the same type of contraction, construction and expansion joints specified in the concrete base shall be continued across the kerb.

i) Where applicable the top of gully pits shall be reconstructed or precast units adjusted, to suit new kerb profile in accordance with Technical Notes for CONCRETE WORKS.

Backfilling and Restoration

a) Backfill material behind the kerb shall consist of granular material, free of organic material, clay and rock in excess of 50mm diameter, or material as approved by the Engineer.

b) After the new kerb has been constructed and not earlier than three days after placing, the spaces on both sides of the kerb shall be backfilled and reinstated in accordance with the Drawings, or as instructed by the Engineer, free draining and free from surface undulations and trip hazards and in accordance with any surface treatment shown on the Drawings.

c) Backfill material behind the kerb shall be compacted in layers not greater than 150mm thick, to a relative compaction of 95 per cent, when tested in accordance with AS 1289.5.4.1, for standard compactive effort. The work shall be finished in a neat and workmanlike manner.

d) Pavement material adjacent to new kerb shall be backfilled in accordance with the Drawings or as directed by the Engineer.

Adjustment to Gully Pits In the event that adjustment of line or level of the kerb requires adjustments in gully pits the Contractor shall undertake any necessary partial demolition and shall reconstruct such sections of the gully pits as are necessary to match the design standard of the existing gully pit.

12. Tolerances

The finished product shall be true to the drawing dimensions and finish specified. Tolerances for driveway shall be in accordance with the following requirements: a) The top surface of the layback shall be parallel to the ruling grade of the

pavement and free from depressions exceeding 5 millimetres when measured with a three metre straight edge;

b) Level ±5 millimetres; c) Line ±10 millimetres to face of layback or gutter line; d) Cross-section dimensions ±5 millimetres; e) Width ±10 millimetres

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13. Roads

Road Pavement Design Specification Roads within the City of Fremantle municipal boundary shall be flexible pavements and shall be designed in accordance with the latest version of the following: a) "Guide to Pavement Technology Part 2 - Pavement Structural Design"

(Austroads 2012) "Engineering Road Note 9 - Procedure for the Design of Flexible Pavements" (MRWA 2012)

b) Road pavements shall be designed for a minimum 40 year design life, with no maintenance required for the first ten years and minimum maintenance required for the design life under the anticipated traffic loading.

Design of the pavement shall involve consideration of the following five inputs: Design Traffic Loading a) Sub-Grade Evaluation b) Environmental Impact c) Pavement and Surfacing Material d) Construction and Maintenance

Road pavement design shall be carried out by a qualified engineer with appropriate knowledge of pavement design in the local environment. The pavement design, including all considerations, assumptions, sub-grade test results, calculations, detailed drawings and any other relevant documentation shall be submitted to the City of Fremantle, Infrastructure Engineering Unit for endorsement prior to the commencement of construction and/or procurement of materials. Drawings provided shall clearly indicate the structure, material types and thickness of each layer of the proposed pavement and surfacing. Any variation to these requirements may be accepted by the City of Fremantle in special circumstances. Rigid pavement design may be considered in special circumstances, through consultation with the City of Fremantle. Surface & Base Material: For specification of the road surface and base material refer: MRWA Specification 302 – Earthworks and spec 501-Pavements. Road Surface Material Specification a) Road surface shall be designed for a minimum of 25 years design life. b) Class C320 bitumen binder with 75 blow Marshall properties shall be used and

shall comply with AS2008-1997. c) Asphalt shall be laid in accordance with AS2150-2005. Asphalt shall not be laid

if the temperature of the surface taking asphalt is less than 10°C.

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Asphalt specification for red surfaces a) Dense graded asphalt with 10mm nominal stone size b) 2% red Oxide with Laterite Stone c) For bus lanes, the mix used shall have granite aggregates consisting of 30% by

mass of the total aggregates used.

Tolerances Values for testing of road surface tolerances shall be measured at 10m intervals for each trafficable lane. Final levels of surface shall be within 5mm of the final design levels. Where the base pavement conforms to the appropriate standard(s), the road surface shall only be accepted if the tolerance values given in Table 15, AS2150-2005 for 'heavy and very heavy traffic roads' are met. For all road classifications (excluding access roads) in the road hierarchy, the road surface shall only be accepted if the tolerances values given in Table 16, AS2150-2005 for 'Major roads, heavily trafficked' are met. Testing a) All testing shall be conducted in accordance with the relevant Australian

Standard and/or Main Roads WA Standards, by a NATA qualified independent testing authority in accordance with AS1289:2014.

b) Samples of asphalt thickness and density shall be taken from six cores for every 1500sqm of pavement area, or otherwise specified.

c) The layer thickness shall be accepted if the average thickness is not less than 10% of the design thickness and does not exceed the design thickness by 20%.

d) The density shall be considered non-compliant if at any location it is measured to be less than 94% of the laboratory compacted density of the design mix.

e) All road surfaces shall be tested for ponding by spreading an adequate amount of water on the surface. Any ponding shall be rectified by the Contractor.

Non-Conforming Road Surface If the road surface does not conform to any of the specified requirements, the road surface shall be profiled and resurfaced with fresh asphalt. Resurfacing shall have a minimum transverse width of the trafficable lane and a minimum longitudinal length of 20m. The corrected pavement will be subjected to re-testing to ensure it conforms with all of the specified requirements. The City will bear no cost for any correction done for non-conforming surfaces. Road Base Design Guidelines Road base and sub-base design shall be in accordance with the guidelines provided in this document and shall be in accordance with MRWA Specification 302 - Earthworks & MRWA Specification 501 - Pavements.

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Crushed Limestone Particle Size Distribution grading for portion passing a 75mm AS sieve AS Sieve Size Required Percentage (mm) (%) passing by mass 75.00 100 19.00 55-85 2.360 & less 35-65 a) Percent (%) of wear of crushed limestone not to be less than 30% or exceed

55% (calculated by the Los Angeles test). b) Calcium Carbonate Content (CaCO3) shall not be less than 60% or greater than

80%. c) Maximum Dry Compressive Strength (MDCS) shall not be less than 700 kPa. d) Location where tested material was placed must be indicated on a locality plan. Crushed Rock Crushed Rock shall be manufactured from hard, durable stone, free of clay, organic matter and other deleterious material. The crushed rock shall be freshly blended prior to delivery and conform to the following table. Particle Size Distribution: (Grading for portion passing a 26.5mm AS Sieve) AS Sieve Size Required Percentage (mm) (%) Passing by mass 26.50 100 19.00 95-100 13.20 78-92 9.500 63-83 4.750 44-64 2.360 30-48 0.425 14-22 0.075 & less 6-10 Ratio of the portion passing the 0.075mm sieve to the portion passing the 425mm sieve shall fall within the range of 40-60%. Material Constraints for portion of sample passing the 0.425mm sieve: Material attribute Required measurement Liquid Limit not greater than 25% Plasticity Index not greater than 5 Linear Shrinkage not greater than 2% Max. Dry Compressive Strength not less than 2 MPa Los Angeles Abrasion loss not greater than 35% Wet Strength not less than 100kN Wet/Dry Strength Variation Ratio not greater than 40%

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Flakiness Index not greater than 35 Soluble Sulphate Salt Content not greater than 0.1% (expressed as percentage sulphate by mass of crushed rock). Location of where tested material was placed must be indicated on a locality plan. Sampling and Testing Sub-base and Base Course Material At the commencement of production or supply of base course material, the Contractor shall take two representative bulk-samples from the first 500t of each material. During placement, the Contractor shall take at least one representative bulk-sample of the material from each successive 2000t of material from each source to be used at the site of the works. All test results shall be submitted to the Engineer, Infrastructure Engineering for approval and shall include at least the information listed in the conformity tables in the preceding paragraphs for the sub-base and base course material. Construction: Delivery and Spreading Pavement material shall not be placed on the sub-grade or previous layers of pavement until a City of Fremantle Infrastructure Engineering Representative has given their approval. Material shall not be placed over a layer weakened by moisture. Crushed materials, when delivered shall have moisture content with + 2% of the modified optimum moisture content. Material shall be spread in uniform layers as near as practicable to the required thickness by direct tipping from suitable vehicles. Care shall be taken to avoid segregation of material during tipping and spreading. The tipping of material in heaps and spreading by grader is to be avoided. If material becomes segregated it shall be remixed. Construction: Testing and Sampling The number of tests and location of all tests shall be determined in accordance with AS3798-2007. All laboratory testing shall be by a NATA qualified independent testing authority in accordance with AS1289:2014. Construction: Dryback Requirement Asphalt works cannot be programmed until the sub-grade, sub-base and base course have met Dryback requirements. Dryback requirements shall comply with MRWA Specification 501.27 Use of Recycling Materials Environmental impacts will be prevented, minimised and managed in city activities while creating and maintaining a resilient, diverse and attractive environment. The City of Fremantle supports the increased recovery and use of recycled materials to minimise our environmental impact by reducing the consumption of natural resources. This will minimise our contribution of extracting unsustainable quantities of

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natural resources and provide sustainable solutions to protect the availability of these resources for future generations. Selecting Recycled Materials The selection of recycled materials shall be in accordance with "Recycled Materials in Road Pavements Specification" (IPWEA NSW 2010) Each material class (Base, Sub-Base etc.) must conform to the properties outlined in IPWEA specification for recycled materials. The supplier must provide certification of material testing by a NATA qualified independent testing authority in accordance with AS1289:2014.Stabilised road base material can be used for road construction, but the specification for these materials shall be lodged to the City prior to proceeding with the pavement design. Compaction and Placement of Recycled Materials When using recycled materials, appropriate method of compaction and placing technique shall be employed to avoid the possible breakdown of weakened constituents during construction.

14. Cycle Path

For specification of the Shared Path Design refer Department of Transport Shared Path design Technical Guidelines

15. Strom Water Drainage- Guideline

Design calculations Design Average Recurrence Intervals. The average recurrence intervals (ARI) for the design of piped drainage systems in a residential, commercial or industrial area will depend on the local circumstances of the catchment area. Type of Catchment

a) Central Business District b) Commercial/Industrial Areas c) High Rise, /Multiple residential(outside CBD) d) Residential Area e) Street Drainage System

Runoff Coefficients

The runoff coefficient can be calculated as the average (weighted by area) of the coefficients chosen for the portions of differing permeability. The adopted range of runoff coefficients for the City of Fremantle are as shown below:

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Paved Surfaces ................................................................. 1.0 Intensely developed commercial & industrial areas .......... 0.9 Single Residential development ........................................ .0.5 The stormwater runoff from properties are required to be retained onsite. If due to special circumstances such as multi-unit developments the water cannot be suitably retained on site, a connection to the Council's drainage system may be considered. Rainfall Intensity-Frequency-Duration The rainfall intensity-frequency-duration relationships are to be as set out in"Australian Rainfall and Runoff, A Guide to Flood Estimation". The Rainfall Intensity Chart for Fremantle Information from Bureau of Meteorology

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Time of Concentration Travel times may be calculated from charts for overland flow and gutter flows contained in the Australian Rainfall and Runoff publication, together with pipe and channel flow charts. The minimum time of concentration shall be taken as 5.0 minutes. Flooding Hazards Tailwater Level Assumption. An allowance of 1600mm change to the sea level due to climate change must be assumed for the design of minor drainage systems, where the stormwater rainage discharges into tidal waterways such as the Swan River. If tailwater is critical for managing major flows and setting flood immunity, a sensitive check must be undertaken to examine impacts of higher sea level in accordance with best climate change predictions at the time. Hazard Estimation For pedestrian safety the following criteria apply: The velocity x depth product in a roadway in the designed major storm event is not to exceed 0.6 m2/s in the channel, kerb and the footpath. Stormwater Pipes Each section of pipe or conduit shall be designed to flow full and operate under pressure. The hydraulic design of pipe size shall be based on the Colebrook-White formula using the charts for roughness coefficient K. Reinforced Concrete Pipe.......... K = 0.6 UPVC Plastic.............................. K = 0.015 Clay............................................ K = 0.15 The maximum and minimum velocity for full pipe flow shall be 4.5 m/s and 0.75m/s respectively. The pipe sizes shall have a minimum capacity designed for a storm event of average recurrence interval as outlined below.

Type of Catchment Storage Tank Drainage System

A,B &C 1 IN 100 ARI 1 IN 20 ARI D Retained on Site 1 IN 5 ARI E N/A 1 IN 20 ARI

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Loading & Overburden of Pipes Steel reinforced concrete pipes shall be designed for installation in accordance with "AS/NZS 3725:2007 - Design for installation of buried concrete pipes." with the following exceptions.Clause 6.5 of AS/NZS 3725 shall be replaced by: The defects of superimposed live loads shall be calculated in accordance with AS5100.2-2004Distribution of live loads shall be in accordance with AS5100.2-2004 Dynamic load allowance shall be as follows: a value of 0.4 for zero height; a) A value of 0.1 for fill heights of 2m of higher b) A linear interpolation between 0.4 and 0.1 for depths between zero and 2m

depths respectively. Construction load cases shall be considered in addition to load cases associated with compaction of fill material. Pit energy losses and pressure changes shall be taken into account for the hydraulic grade line analysis. For reliable values of energy losses and pressure changes for different types of pits and junctions, it's recommended that "Missouri Charts" are used. Pipe Capacity Assumptions

a) Pipe capacity for trunk stormwater systems is to be estimated using hydraulic

grade line analysis of the drainage system for the relevant design storm and using a suitable computer model.

b) For smaller pipelines, the capacity can be estimated using pipe flowing full at grade assumptions. The adopted pipe velocity when using this method must not be less than 3 m/s.

Soakage Sump The sump for soakage purposes shall be designed to cope with the accumulated storage resulting from the runoff from a design storm of 1 in .20 years ARI to 1 in 50 years ARI depending on its location. A check shall also be made for a design storm of 1 in 100 years ARI in order to determine its impact on the surrounding land and installations. In estimating storage requirements a mass - curve technique may be used. An example of this procedure is given in Book Eight, Technical Note 1 of ARR 1997. The City presently uses a simple inflow and outflow hydrograph relationship to analyse the storage capacity of soakwells. A soil investigation shall be carried out to determine the soil parameters required for the storage analysis of the sumps.

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Detention Systems On-site detention system may be designed to restrict peak outflows for selected design storms to either pre-development conditions, or to the maximum capacity of the existing downstream drainage network. If stormwater cannot be disposed of on-site due to adverse site conditions then connection to the City's street stormwater system may be considered. Approval of the proposed connection may require the installation of large on-site holding tanks to retain the critical storm. These on-site detention systems shall be designed to reduce the peak runoff from the developed sites for a once in a hundred (1:100) year storm to the runoff which would have occurred in a natural state of a once in twenty (1:20) storm of a duration equal to the natural time of concentration. The maximum allowable discharge to the City's system is 120litres/second/hectare of site and the minimum storage requirement is 290 cubic metres/hectare of site. In designing the storage tank allowance should be made for the additional area that may be created by high rise buildings on the site. A detailed design must be submitted to the City of Fremantle‘s Infrastructure Engineering Section before any drainage connection approval will be considered.

Retention Systems Stormwater retention systems can be designed to reduce the total annual runoff volume and reduce the runoff volume from a specified design storm. Grassed and Vegetated Drainage Channels The application of ground channels is genuinely limited by the design standards and site conditions. Consideration should be given to the incorporation of the principles of natural channel design for the design of such drainage channels. All drainage channels of this design should have a natural appearance and fit with its surroundings. Refer Stormwater Management Manual for Western Australia (WA 2004-2007). Free Board The Free Board level required is 300mm, this is the level between a flooded road reserve and the floor level of commercial/residential properties or carparks. Where the level of a property or carpark is below the level of the top of kerb it is required that in between is a raised footpath that is 100mm higher than the top of kerb. This requirement minimises the risk of flooding to private properties and carparks. Non-Aggressive Ground Conditions To install a pipe underground or above ground in ground conditions considered to be Non-aggressive, the following must apply: a) The pipe must not come in to contact with salt-water or salt spray b) The pipe must not be subject to and tidal conditions or forces c) Internal and external surfaces of pipes exposed only to fresh or brackish water

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d) The soil and ground conditions are not contaminated with Acid Sulphate Soil, as per the Department of Environment Regulations guidelines. (DER 2015)

Marine Environment To install a pipe underground or above ground in ground conditions considered to be a Marine Environment, the following must apply: a) Only the external pipe surface is to come in contact with salt water or salt spray b) The soil and ground conditions are not contaminated with Acid Sulphate Soil, as

per the Department of Environment Regulations guidelines. (DER 2015) Acid Sulphate Soils Planning of stormwater drainage systems within potential acid sulphate soil zones must be undertaken with considerations for items such as, but not limited to: - Highly acidic soils affect on the surrounding and downstream environment; - The potential that groundwater is also highly acidic; and - The acidic conditions affect on existing and new infrastructure. The Department of Environment and Conservation has produced guidelines to assist with the identification, treatment and management of acid sulphate soils within Western Australia. Refer Identification and investigation of acid sulfate soils and acidic landscapes (DER 2015) and Treatment Subsoil Drains Subsoil drains shall be provided where necessary to control ground water table and flow. Subsoil drainage systems are to be designed and constructed in accordance with "AS/NZS3500.3:2003 - Plumbing and Drainage: Part 3 - Stormwater Drainage." For subsoil drains, only approved perforated or slotted pipes and conduits shall be used. Drain cells or nylex strip drains shall be laid in a granular filter medium wrapped with an approved geotextile filter membrane. Design Drawings The proposed drainage design shall be clearly shown on plan drawings to a scale of 1:250, 1:500 or 1:1000 depending on the size of the project. Longitudinal sections of the proposed drainage pipe networks shall also be provided. All underground and above ground public utility services shall be clearly indicated on the plan drawings. Legends and symbols shall be clearly shown on the drawings, using standard notation wherever possible.

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16. City of Fremantle - Guidelines for better management of Urban Stormwater for Commercial Properties

These guidelines provide information on simple practices that can be employed to Prevent contamination of the stormwater system by commercial properties and Businesses especially where storm water from the premises is discharged into Council's storm water drainage system. Only rainwater is allowed to enter the stormwater drainage system. Anything other than rainwater will pollute the receiving water bodies.

• Used water from inside commercial businesses is wastewater. Wastewater

must not be discharged into stormwater drains. This includes water from swimming pools, air conditioners, window washing and mop cleaning.

• Wastewater that meet Water Corporations requirement should be directed to the sewer. Businesses should make their staff aware of disposal points for wastewater.

• Litter and sediment should be swept and disposed of in waste bins or recycled and not washed into drains.

• Bins should be washed in the designated bin wash area on the premises. Bin wash areas are required where bins are likely to be soiled or where businesses produce putrescible waste. Waste bins should not be allowed to overflow. Unsecured wastes can be blown into the stormwater drains and cause local flooding.

• Cardboard, paper, oil, drums, bottles and other materials that can be recycled should be recycled. Different bins to separate general waste from recyclables should be provided and identified.

• Spillage from oil and liquid storage areas can block stormwater drains and contaminate the stormwater system. Spills should be picked up using absorbent materials and disposed of into commercial bins and not hosed away. Chemicals and liquids should be stored away from stormwater drains and pits.

• Compliance with the Health Act 1911 and Environmental Protection Act 1986 with regards to Waste Management and discharges into the environment.

17. Guidelines for better management of Urban Stormwater for Residential

Properties

These guidelines provide information on simple practices that can be employed to prevent contamination of the stormwater system by residential properties especially where storm water from the premises is discharged into Council's stormwater drainage system. Only rainwater is allowed to enter the stormwater drainage system. Anything other than rainwater will pollute the receiving waterbodies.

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a) Used water from inside residential properties is wastewater. Wastewater and must not be discharged into stormwater drains. This includes water from swimming pools, air conditioners, window washing, car washing and mop cleaning. Wastewater that meet Water Corporations requirement should be directed to the sewer.

b) Litter and sediment should be swept and disposed of in waste bins or recycled and not washed into drains.

c) Bins should be washed in the designated bin wash area on the premises. d) Waste bins should not be allowed to overflow. Unsecured wastes can be blown

into the stormwater drains and cause local flooding. e) Cardboard, paper, bottles and other materials that can be recycled should be

recycled. f) Compliance with Health Act 1911 and Environmental Protection Act 1986 with

regards to Waste Management and discharges into the environment. (Further information)

18. Reinstatement of Flexible Pavement

The reinstatement of sub-grade and pavement after trenching works must be carried out in accordance with the following specifications.

General Erect adequate hoardings and/or barriers around the area to be excavated and implement appropriate Traffic Management in accordance with the City of Fremantle Procedure for Traffic Management within the Road reserve. a) Make a neat saw cut to existing asphalt surfaces. b) Keep the width of the excavation trench to a minimum. c) Excavated material shall not be reused in the reinstatement to trenches and

shall be removed from the site. d) Roads and footpaths are to be reinstated to previous existing levels. e) For longitudinal trenches (in roads) that are greater than 50m long, the

resurfacing shall be carried out for the full width of the trafficable lane and shall match the previous existing asphalt layers.

f) All the construction joints on road surfaces shall be located away from the traffic wheel path/track. Where possible, joints in wearing course shall be located beneath traffic lane marking.

g) For asphalt surfaces, asphalt edges shall be tacked with bitumen emulsion prior to new asphalt being laid with a minimum rate of 0.6 l/m².

h) For asphalt surfaces, asphalt shall be laid in accordance with AS2150-2005. i) For asphalt surfaces, the wearing course shall extend 150mm either side of

the excavated trench. j) The outer edge shall be saw cut and the shape of the patched area must be

square or rectangular.

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Installation and Backfilling of Pipelines and Conduits

a) Install pipes and conduits larger than 100mm in diameter on a 100-150mm layer

of compacted sand. b) Backfill pipes and conduits larger than 100mm in diameter with stabilised sand

(4% by volume) compacted to a minimum of 95% Modified Dry Density.

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Base, Sub-Base and Sub-Grade Layers:

• Limestone Road Base shall be compacted to a minimum 98% Dry Density Ratio.

• Limestone Road Sub-Base shall be compacted to a minimum 95% Dry Density Ratio.

• Limestone Footpath Base shall be compacted to a minimum 95% Dry Density Ratio.

• Limestone shall be laid in layers no more than 250mm nor less than 100mm thick.

• Sub-grade shall be compacted to a minimum 95% Modified Dry Density. • The pavement shall be compacted using mechanical compactors. • Hand operation must be used in confined areas where compaction cannot be

achieved by mechanical means.

Asphalt Wearing Course New works not trench reinstatement • For asphalt roads and footpaths, the asphalt shall be laid and compacted in 30

mm layers of DGA 10mm granite aggregate with C320 bitumen and 75-blow. Marshall Properties.

• For major intersections, the asphalt shall be laid and compacted in one layer of

50mm with DGA 14mm granite aggregate with C320 bitumen and 75-blow Marshall properties, in accordance with MRWA intersection mix.

If the wearing surface is red, reinstatement must match existing. The top layer shall be laid and compacted in minimum 30mm with Red Asphalt DGA 10mm Laterite or Laterite/granite aggregate with 2% oxide, matching with existing Surface. Testing

a) Sub-Grade Compaction: The sub-grade shall be compaction tested at a

minimum rate of one test per 30 linear metres and one test for each section between structures less than 30m apart under pavements. Particular emphasis on testing will be made to ensure that adequate compaction has been achieved around structures. The above notwithstanding, a minimum number of 3 tests shall be carried out for each Test Lot. Tests may be carried out using sand penetrometer or nuclear testing.

b) Base & Sub-Base Layers: The base course and sub-base shall be compaction

tested at the minimum rate of one test per 30 linear metres and one test for each section between structures less than 30m apart. The above notwithstanding, a minimum number of 3 tests shall be carried out for each Test Lot. Tests may be carried out using sand penetrometer or nuclear testing.

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c) Asphalt Layer: Audit core tests of the asphalt layer may be required at 30m intervals or as otherwise specified, as directed to determine Marshall density/stability, thickness of asphalt course, bitumen content and percentage air voids.

d) Samples shall be taken and tests carried out by a NATA registered laboratory.

19. On Street Parking Dimensions

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Accessibility Requirements Walkways, ramps and landings shall comply with AS 1428.1. Tactile ground surface indicators shall be provided at the following locations. Kerb ramps and step ramps Pedestrian Crossing at roadways

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20. Appendix

Standard Drawings Reference Documents Australian Standards AS 1012.1 Sampling fresh concrete AS 1012.3.1 Determination of properties related to the consistency of concrete

Slum Test. AS 1012.8 Making and curing concrete compression, indirect tensile and flexure

test specimens in the laboratory or in the field. AS 1012.9 Determination of the compressive strength of concrete specimens. AS 1012.14 Securing and testing cores from hardened concrete for Compressive

strength. AS 1141.14 Particle shape by proportional calliper AS 1141.21 Aggregate crushing value AS 1141.23 Los Angeles value AS 1141.24 Soundless (by use of sodium sulphate solution) AS 1289.3.3.1 Calculation of plasticity index of a soil AS 1289.5.1.1 Determination of the dry density/moisture content relation of a soil

using AS 1289.5.2.1 Determination of the dry density/moisture content relation of a soil

using modified compactive effort AS 1289.5.4.1 Compaction control test – Dry density ratio, moisture variation and

moisture ratio. AS 1302 Steel reinforcing bars for concrete AS 1303 Steel reinforcing wire for concrete AS 1304 Welded wire reinforcing fabric for concrete AS 1379 The specification and manufacture of concrete AS 1478 Chemical admixtures for concrete AS/NZS 1859 Reconstituted wood-based panels AS 2082 Visually stress-graded hardwood for structural purposes AS 2271 Plywood and blockboard for exterior use AS 2758.1 Concrete aggregates AS 3600 Concrete structures AS 3610 Formwork for concrete AS 3799 Liquid membrane-forming curing compounds for concrete AS 3972 Portland and blended cements AS1742.3 Traffic Control for Works on Roads AS 2876 Concrete kerbs and channels (gutters) Manually or machine placed

(Austroads 2012) Guide to Pavement Technology Part 2: Pavement Structural Design.

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(DGLWA 2011) Asset Management - Framework and Guidelines (IPWEA NSW 2010) Recycled Materials in Road Pavements Specification (IPWEA WA 2002) Restoration and Reinstatement Specification (MRWA 2012) Engineering Road Note 9 - Procedure for the Design of Flexible Pavements (MRWA 2013) MRWA Specification 302 - Earthworks (MRWA 2012) MRWA Specification 501 - Pavements (MRWA 2015) MRWA Specification 504 - Asphalt Wearing Course (MRWA 2015) MRWA Specification 510 - Asphalt Intermediate Course Referenced Australian Standards AS 1289:2014 Methods of testing soils for engineering purposes (Note: Multiple parts available, refer all appropriate parts). AS 2008-2013 Bitumen for Pavements AS 2150-2005 Hot mix asphalt - A guide to good practice AS3798-2007 Guidelines on earthworks for commercial and residential developments.

Engineering Technical Guidance Notes

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