Drainage Design Report. for. Residential Development. Morristown Biller, Newbridge, Co. Kildare. Job No: D1493-1

Transcription

1 Drainage Design Report for Residential Development at Morristown Biller, Newbridge, Co. Kildare. Job No: D Client: DDA Architects Date: October 2017 Local Authority: KIldare County Council Revision: Planning PL5 ( ) Calmount Park, Ballymount, Dublin 12. Tel: Fax: Ulick Burke & Associates Limited. Registered in Ireland No: V.A.T. Registration No: IE Registered Address: Unit G3, Calmount Park, Ballymount, Dublin 12. Directors: U.Burke, R.Burke, P.Kavanagh

2 Contents: Introduction Surface Water Attenuation Calculations Surface Water Network Design Specification/Product Information for; a) Separators b) Silt Trap c) Flow Control Devices Foul Sewer Network Design

3 Introduction: The current proposal on completion will form part of an overall housing development referred to as The Paddocks. This development is located immediately south-east of an existing housing development known as The Meadows. For the purpose of this document the existing and proposed developments are referred to as the following: Phase 1 The Meadows existing housing development by previous applicant Patrick Byrne as granted planning permission under application Reg. Ref s. 11/264 & 05/2160. Phase 2 (Retention Application) the recently granted application for retention & completion of 39 No. houses by applicant Stennock Ltd. Planning Reg. Ref. 16/1013. Construction works are ongoing relating to this part of the development. Phase 2 (Subject Application) the remaining Phase 2 lands which is the subject of this planning application for 281 No. dwellings and 1 No. Crèche. The main civil engineering design elements associated with the residential development are foul & surface water drainage including SuDS compliant surface water attenuation, watermain layout, roads layout and gradients plus finished floor level design in relation to both the topographical survey and the surrounding levels of the proposed development in general. All such elements are detailed on the accompanying drawings. The salient issues are summarised as follows; Surface Water Drainage & Attenuation; The existing Phase 1 development by others discharges surface water through an existing surface water outfall pipe which crosses the Morristown Road, enters the Phase 2 lands and ultimately exits these lands through the site s north-eastern boundary where it connects with the Local Authority surface water drainage on Station Road after traversing a portion of the adjacent sports grounds. This route was originally established through the Phase 1 planning applications by others. The discharge pipe was also put in place by others for a previous planning application prior to any works being carried out on site by the subject applicant. The works relating to this part of the development are entirely contained within the applicant s landholding. There is no works extending to third-party lands. Due to the inextricable link between Phase 1 and Phase 2, as part of the retention application for part of Phase 2 we carried out extensive research on site to establish the existing surface water layout including confirmation of the presence of any existing surface water attenuation systems. We concluded after much investigation that Phase 1 by others had elements of surface water attenuation in place however there was no flow control device fitted to the system. On analysis of the existing surface water drainage network we concluded that the placing of a flow control device on the system would introduce runoff water backup in the system which would exit through low lying road gullies.

4 This existing system was not suitable for the inclusion of a flow control device therefore we have allowed the full Phase 1 runoff flow (199 l/sec) to discharge into the subject Phase 2 where a full new surface water attenuation system will be installed to cater for both the existing and proposed development. Refer to the enclosed Drainage Design report Appendix A for explanation of the Phase 1 incoming flow of 199 l/s into the subject Phase 2 SW drainage network. The single attenuation system shown on Drg. D D1-2 is the overall system for a) The Meadows development plus b) the Phase 2 houses that were the subject of the recent retention application plus c) the subject development. As a result of this overall design approach, all runoff from the entire development (The Meadows and The Paddocks), will be SuDS compliant on completion of the works. Refer to Drg. No. D D4 for a site plan of the areas contributing to the attenuation facility. The climate change factor of 20% has been incorporated into the design by applying the 1.2 factor to rainfall intensities within the attenuation storage and flood storage calculations. This enlarges the attenuation volume to ensure additional capacity exists should climate change increase rainfall intensities. The flow restriction arrangement for Phase 2 includes a two-tier system as set out in SuDS design. The first flow control device will limit the flow to Q2 this device will be located within a downstream manhole at a level of the base of the attenuation tank (while allowing a predefined depth below for infiltration storage). The second device will be located higher up within the same manhole at the design height of where the attenuation storage is at its maximum and the flood storage begins. Therefore, for the first 5mm of rainfall on the site nothing will pass through the flow control devices as this runoff will infiltrate through the base of the attenuation system. When the flow subsequently increases, attenuation flow begins and the Q2 flow control device is activated. Thereafter when the flood water in the system reaches the design flood attenuation base level the upper flow control device is activated i.e. activating an additional discharge rate equal to the balance of the Q30 flow. Longitudinal sections accompany this report showing sections of all the surface water pipes within the subject development. Irish Water Correspondence in relation to Waste Water & Water Supply While waste water & water supply are discussed separately in this document, the correspondence from Irish Water is noted as follows: A Pre-Connection Enquiry was submitted to Irish Water and the response to this is enclosed in Appendix B, dated 05/06/2018, Ref: CUST17776 Rev 1 Connection of Strategic Housing Development of 320 No. (Revised from 193 Units) houses & Creche at Station Road, Newbridge. This document noted that subject to a valid connection agreement being put in place and the conditions listed by Irish Water, the proposed connection to the Irish Water network can be facilitated. In summary the conditions are as follows;

5 A) Obtain a Statement of Design Acceptance from Irish Water. Document enclosed in Appendix B also. B) Irish Water correspondence is subject to a connection agreement being signed and the appropriate connection fee being paid at a later date. Condition Noted: The connection agreement will be entered into and relevant payment made by the Developer at a later date. C) A Public Works Services Agreement (PWSA) must be entered into by the Developer to confirm available capacity and & to determine the full extent of any water or wastewater upgrades which may be required to be completed to Irish Water Infrastructure. The Developer has actively engaged with Irish Water regarding the Public Works Services Agreement. This matter is ongoing. D) Timelines and phasing of the development and any upgrades will be subject to the PWSA investigations. Condition Noted. E) Provision of a Deed of Easement all foul & water pipelines in the development & protection of the Existing 300mm diameter foul sewer will be a requirement of the connection agreement. Noted Agreement to be formed at a later date. Waste Water; Similar to the surface water drainage arrangement regarding interactions between Phase 1 & Phase 2, the foul sewer network is common to both phases with the outfall being within the subject Phase 2 lands discharging to an existing manhole in neighbouring lands as detailed within previous planning applications by others under planning Reg. Ref s 11/264 & 05/ houses exist in the Phase 1 development (The Meadows) which equates to 1764 DU/house. Allowance is made in the subject Phase 2 foul network for this 11 l/s from the existing Phase 1 development. Refer to Drainage Design Report foul sewer design calculations showing the Phase 1 11l/s included as a base flow in the overall network design. An existing 300mm diameter foul sewer traverses the subject Phase 2 lands in a west to east direction. This pipe will be retained in its entirety and is located on the proposed link street thus ensuring ease of access and availability for taking in charge in the future subject to the normal application and procedures. Foul sewer longitudinal sections accompany this report showing sections of all the foul sewers within the subject development.

6 As noted above the existing Phase 1 foul sewer (peak flow: 11 l/s) and the proposed Phase 2 foul sewer forms one drainage network (with peak flow 31 l/s including the phase 1 11 l/s) with one outfall location. Both phases of the development will be fully integrated regarding access roads, drainage and utilities. Regarding maintenance of the foul sewer in the context of taking in charge it is envisaged that the development proposed will be constructed to Kildare County Council & Irish Water standards throughout with the view to entering into the taking in charge process at the appropriate time in the future. Maintenance of the foul sewer will not require any special approach the pipework is designed to the standard code guidelines and the system is fully gravity flow. Apart from standard periodic maintenance inspections there should not be any ongoing involvement regarding the operation of the foul sewer. Water Supply: As per the foul sewer and surface water drainage arrangements mentioned above the rationale behind the watermain proposal is similar, i.e. the proposed Phase 2 watermain will be connected to the existing Phase 1 main thus forming a larger loop serving all the Phase 1 & Phase 2 lands. Following consultation with Kildare County Council s Water Operations & Maintenance division as part of the Phase 2 Retention Application, the following information was obtained: Water pressure readings were recorded by Kildare County Council s Operations & Maintenance staff and as reported by the KCC Engineer all readings were of sufficient pressure as to not be a concern regarding the subject development. It was also noted that water quantity would not be a problem either as the general area is served from a nearby 400mm watermain on Station Road. Therefore, the proposal of forming connection for the subject application with the existing Phase 1 and Phase 2 development did not pose any issue with the Operations & Maintenance Dept. As part of the Phase 2 retention application the proposed connection locations were identified at the two spur roads which are currently fenced and gated between Phase 1 & Phase 2. The existing watermain within Phase 1 is a 150mm diameter pipe which will also be provided in Phase 2. This new watermain will be looped with adequate valves and chambers and as noted by KCC Operations & Maintenance Dept. water pressure or quantity issues will not be a problem. The route of the east-west link street has been agreed with Kildare County Council during course of the retention application. The joining of this street with the extension of the adjacent access road within the existing apartment development to the north-east of the site had been coordinated with the adjacent landowner to ensure a seamless transition at the site boundary.

7 Surface Water Attenuation Calculations Please also refer to Drg. No. D D4 for layout showing site areas contributing to the attenuation facility.

8 Surface Water Attenuation Calculations (for Phase 1 and Phase 2 catchment): 1) Interception Storage Calculate runoff from 5mm of rainfall on developed area. For this calculation only hardstanding areas are assumed to provide 80% runoff, and non-hardstanding areas are assumed to provide 0% runoff. The equivalent volume of Interception Storage should be provided on site as no discharge from site should occur for this initial 5mm depth of rainfall. The Interception Storage on this subject site will be provided through the base of attenuation tank located on the site. Catchment Area (Entire phase 1 and phase 2 total): m 2 (14.502ha) Landscaping (in both phases): 30121m 2 Permeable Surfacing (phase 2): 2825 m 2 Impermeable Areas (in both phases): Hardstanding and Roof Areas: 69348m 2 Design Impermeable Areas: 69348m 2 x 0.8 = 55478m 2 Total volume for 5mm rainfall: 5mm x 55478m 2 = 277m 3 Therefore a minimum Interception Storage volume of 277m 3 should be provided. This will prevent discharge from site during rainfall events of up to 5mm rainfall. 2) Greenfield Runoff Rate QBAR, (mean annual flood flow): QBARrural (m 3 /sec) = x AREA 0.89 x SAAR 1.17 x SOIL 2.17 SAAR (E ,N ): 900mm Soil Index: S1 (very low runoff) S2 S3 (moderate runoff) S4 S5 (very high runoff) Soil = 0.1(Soil1) + 0.3(Soil2) (Soil3) (Soil4) (Soil5) As the site is relatively small in catchment terms the soil class is 100% Soil2

9 Soil Class: Soil2 Runoff Potential: Low Soil Value: 0.3 QBAR: As the site area is less than 50 hectares; QBAR for 50 hectares is firstly calculated, QBAR (m 3 /sec) = x AREA 0.89 x SAAR 1.17 x SOIL x (0.5) 0.89 x (900) 1.17 x (0.3) l/sec 2.45 l/sec/ha QBAR for the smaller area (i.e. the subject site area): 2.45 l/sec/ha x ha l/sec Calculate flood flows for various return periods; QBAR = Q2 = Q30 = l/sec 0.95 x l/sec = l/sec (ALLOWABLE DISCHARGE based on peak flood flow for 2 year return or 2 l/sec/ha, whichever is greater) Q2 = l/sec applies x l/sec = l/sec The peak flow rate factors of 0.95 & 2.1 above are taken from tabulated values of growth curve multipliers for the Dublin area. Allowable discharge set at l/sec. 2a) Attenuation Volume 80% of hardstand areas are assumed to contribute. Soil SPR Value 0.3, therefore 30% of non-hardstand areas assumed to contribute. Equivalent Runoff Area: 80% x 69348m % x (30121m m 2 ) 55478m m 2 = 65362m 2

10 Met Eireann s Rainfall depths for the 30 year storm event have been used. The table below identified the 12 hour event as the critical event. The rainfall depth used includes a 20% allowance for climate change giving a volume of 2754m 3 - (Column G). A B C D E F G Duration Runoff Area Total Rainfall Depth Revised Depth for Climate Change Total Surface Water (m2) C x 1.2 (m3) B x D Total Permitted Discharge (m3)q2 x A (Q2=33.75 l/sec) Storage Volume Required (m3) E - F 15 min min hour hour hour hour hour day day An allowance to account for the simplifying assumption of head discharge relationship of 1.25 is applied (due to simple calculations assuming the maximum flow rate can be mobilised immediately for each design return period. Revised Critical Volume: 2754 x 1.25 = 3443m 3 Subtract Interception Storage: = 3166m 3 (Req d Attenuation Vol) Arrangement of Flow Control Devices In addition when this storage volume is being used for the 30 year storm event, no surface flooding should occur. At this stage an overflow should be provided whereby the combined discharge from the site should be equal to Q30 (the peak greenfield flood flow for the 30 year return period, i.e l/sec) l/sec will discharge normally with an additional l/sec discharging as an overflow as noted above thus resulting in l/sec overall peak flow. The overflow setting should be such that it is only mobilised once the attenuation storage volume has been used up first.

11 3) Temporary Flood Storage In addition to the previous calculations for interception & attenuation storage, the temporary flood storage must be calculated. The 6 hour duration, 100 year return period must be checked to assess the temporary flood storage required for the site. 100 year 6 hour event, rainfall depth: 54.7mm Factor up by 20% for climate change: 65.6mm Total Volume of Runoff: 65.6mm x 65362m 2 = 4288m 3 Deduct discharge at Q2 for 5hrs: l/sec x 5 hrs = 608m 3 Deduct discharge at Q30 for last hour: l/sec x 1 hr = 269m 3 Storage volume required; 4288 ( ) = 3411m 3 Factor up for head relationship factor; 3411 x 1.25 = 4264m 3 Deduct Interception Storage; 277m 3 Deduct Attenuation Storage; 3166m 3 Temporary Flood Storage Required: = 821m 3 In summary: Interception Storage: 277m 3 to be provided by a lowered base to the attenuation system. Attenuation System Area: 3025m 2. Therefore the Interception Storage Depth will equal 220mm. A lowered base level to the attenuation facility allowing base infiltration will facilitate on site discharge of this interception volume. This storage volume being lower than the system outlet cannot discharge from site. Required Attenuation Volume: 3166m 3 to be provided within the attenuation system on site. Temporary Flood Storage: 821m 3 can also be accommodated within the attenuation system provided see system volumes below. Total volume required: = 4264m 3

12 4) Soil Infiltration Factor Calculation of the soil infiltration factor based on BRE digest: Trench dimensions: 1.5m long x 0.4m wide x 1.6m deep Volume: 0.96m 3 Time to drain from 75% volume to 25% volume: 75% volume to 25% volume: t75-25 = 105min = 6300s V75-25 = 1.5 x 0.4 x ( ) = 0.48 m 3 Internal surface area of the trial pit up to 50% of effective depth: a50 = (1.5 x 2 x 0.8) + (0.4 x 2 x 0.8) + (1.5 x 0.4) = 3.64m 2 f = 0.48m m s f = m/s Time to empty 298m 3 intercepted rainfall (see preceding SUDS compliant Interception storage calculation: t time to empty O outfall (interception volume) A infiltration area (tank base area) f soil infiltration factor t = O A f t = 277m m m/s t = 4381s 73min

13 Met Eireann Return Period Rainfall Depths for sliding Durations Irish Grid: Easting: , Northing: , Interval Years DURATION 6months, 1year, 2, 3, 4, 5, 10, 20, 30, 50, 75, 100, 150, 200, 250, 500, 5 mins 2.6, 3.6, 4.1, 4.8, 5.3, 5.7, 7.0, 8.4, 9.3, 10.6, 11.7, 12.6, 13.9, 15.0, 15.8, N/A, 10 mins 3.6, 5.0, 5.7, 6.7, 7.5, 8.0, 9.8, 11.7, 13.0, 14.8, 16.4, 17.6, 19.4, 20.9, 22.0, N/A, 15 mins 4.3, 5.9, 6.7, 7.9, 8.8, 9.4, 11.5, 13.8, 15.3, 17.4, 19.3, 20.7, 22.9, 24.5, 25.9, N/A, 30 mins 5.6, 7.6, 8.7, 10.2, 11.2, 12.0, 14.6, 17.3, 19.2, 21.7, 23.9, 25.6, 28.1, 30.1, 31.8, N/A, 1 hours 7.5, 10.0, 11.3, 13.2, 14.4, 15.4, 18.4, 21.8, 24.0, 27.0, 29.6, 31.6, 34.7, 37.0, 38.9, N/A, 2 hours 9.9, 13.0, 14.6, 16.9, 18.5, 19.7, 23.4, 27.4, 30.0, 33.6, 36.7, 39.1, 42.7, 45.4, 47.6, N/A, 3 hours 11.6, 15.2, 17.0, 19.6, 21.4, 22.7, 26.9, 31.4, 34.3, 38.2, 41.6, 44.2, 48.2, 51.2, 53.6, N/A, 4 hours 13.0, 17.0, 18.9, 21.8, 23.7, 25.1, 29.6, 34.5, 37.6, 41.9, 45.5, 48.3, 52.5, 55.7, 58.3, N/A, 6 hours 15.4, 19.8, 22.1, 25.3, 27.4, 29.0, 34.1, 39.5, 42.9, 47.6, 51.6, 54.7, 59.3, 62.8, 65.6, N/A, 9 hours 18.1, 23.1, 25.7, 29.3, 31.7, 33.5, 39.1, 45.1, 49.0, 54.1, 58.6, 61.9, 67.0, 70.8, 73.9, N/A, 12 hours 20.3, 25.8, 28.6, 32.6, 35.1, 37.1, 43.2, 49.6, 53.7, 59.3, 64.0, 67.6, 73.0, 77.1, 80.4, N/A, 18 hours 23.9, 30.2, 33.3, 37.8, 40.6, 42.8, 49.6, 56.8, 61.3, 67.4, 72.6, 76.6, 82.5, 86.9, 90.5, N/A, 24 hours 26.8, 33.7, 37.1, 41.9, 45.0, 47.4, 54.7, 62.4, 67.3, 73.8, 79.4, 83.6, 89.9, 94.6, 98.4, 111.3, 2 days 31.8, 39.3, 43.0, 48.1, 51.4, 53.9, 61.6, 69.6, 74.6, 81.3, 87.0, 91.2, 97.5, 102.2, 106.1, 118.8, 3 days 36.3, 44.3, 48.3, 53.8, 57.3, 59.9, 68.0, 76.4, 81.6, 88.6, 94.4, 98.8, 105.3, 110.2, 114.1, 127.2, 4 days 40.3, 48.9, 53.1, 58.9, 62.6, 65.4, 73.9, 82.7, 88.1, 95.4, 101.5, 106.0, 112.8, 117.8, 121.8, 135.3, 6 days 47.6, 57.2, 61.9, 68.3, 72.4, 75.4, 84.7, 94.2, 100.1, 107.9, 114.4, 119.3, 126.5, 131.8, 136.1, 150.3, 8 days 54.3, 64.8, 69.9, 76.9, 81.3, 84.6, 94.5, 104.7, 111.0, 119.3, 126.3, 131.4, 139.0, 144.6, 149.2, 164.1, 10 days 60.6, 72.0, 77.4, 84.9, 89.6, 93.1, 103.7, 114.6, 121.2, 130.0, 137.3, 142.7, 150.7, 156.6, 161.4, 177.0, 12 days 66.7, 78.8, 84.6, 92.5, 97.5, 101.2, 112.4, 123.9, 130.9, 140.1, 147.8, 153.5, 161.8, 168.0, 173.0, 189.3, 16 days 78.1, 91.7, 98.1, 106.9, 112.4, 116.5, 128.9, 141.4, 149.0, 159.1, 167.4, 173.6, 182.6, 189.3, 194.7, 212.2, 20 days 89.0, 103.9, 110.9, 120.5, 126.5, 131.0, 144.4, 157.9, 166.1, 176.9, 185.9, 192.5, 202.2, 209.3, 215.0, 233.7, 25 days 102.1, 118.5, 126.2, 136.8, 143.3, 148.2, 162.8, 177.5, 186.4, 198.1, 207.7, 214.8, 225.3, 232.9, 239.1, 259.1, NOTES: N/A Data not available These values are derived from a Depth Duration Frequency (DDF) Model For details refer to: Fitzgerald D. L. (2007), Estimates of Point Rainfall Frequencies, Technical Note No. 61, Met Eireann, Dublin, Available for download at

14 Project: Morristown Biller Chamber Model - MC-4500 Units - Metric Click Here for Imperial Number of Chambers Number of chambers - 40 Voids in the stone (porosity) - 43 % Base of Stone Elevation m Amount of Stone Above Chambers mm Include Perimeter Stone in Calculations Amount of Stone Below Chambers mm Area of system sq.meters Min. Area sq.meters StormTech MC-4500 Cumulative Storage Volumes Height of System Incremental Single Chamber Incremental Single End Cap Incremental Chambers Incremental End Cap Incremental Stone Incremental Chamber, End Cap and Stone Cumulative System Elevation (cubic meters) (cubic meters) (cubic meters) (cubic meters) (cubic meters) (cubic meters) (cubic meters) (meters)

15 Surface Water Network Design

16 Kavanagh Burke Jenkins Burke Consulting Engineers Page 1 Unit Consulting G3 Engineers Residential Housing Development at Calmount 21 Cookstown Business Ind Park Est Morristown Clondalkin Biller Ballymount, Tallaght Co. Dublin24 Newbridge Dublin Date June 2015 Designed By PJK File Whole Site P9.sws Checked By CADS Storm W.7.3 (c) Micro Drainage STORM SEWER DESIGN by the Modified Rational Method Global Variables Location - Scotland & Ireland Return Period (years) 1 Volumetric Runoff Coeff M Infiltration % 0 Ratio R 0.29 Minimum Backdrop Height Maximum Rainfall (mm/hr) 50 Depth from Soffit to G.L Foul Sewage (l/s/ha) 0.00 Min Vel. (m/s - Auto Design Only) 0.80 O'flow Setting (*Foul only) 0 Min Slope (1:X - Optimisation) 500 Designed with Level Soffits For phase 1 storm water drainage network analysis and the derivation of 199 l/s base flow entering phase 2 storm water network at manhole S17 (See drg. No. D D11-1 for phase 2 network schematic layout) see Windes calculations in appendix A Network Design Table Length Fall Slope (1:X) Area T.E. (mins) DWF k HYD SECT DIA o o o o o o o o o o 225 Network Results Table Rain (mm/hr) T.C. (mins) US/IL E.Area E.DWF Foul Infil. Vel (m/s) CAP Flow

17 Burke Kavanagh Jenkins Burke Consulting Engineers Page 2 Consulting Unit G3 Engineers Housing Residential Development at 21 Calmount Cookstown Business Ind Park Est Clondalkin Morristown Biller Tallaght Ballymount, Co. Dublin24 Dublin Newbridge Date June 2015 Designed By PJK File Whole Site P9.sws Checked By CADS Storm W.7.3 (c) Micro Drainage Network Design Table Length Fall Slope (1:X) Area T.E. (mins) DWF k HYD SECT DIA o o o o o o o o o o o o o o o 225 Network Results Table Rain (mm/hr) T.C. (mins) US/IL E.Area E.DWF Foul Infil. Vel (m/s) CAP Flow

18 Kavanagh Burke Jenkins Burke Consulting Engineers Page 3 Unit Consulting G3 Engineers Residential Housing Development at Calmount 21 Cookstown Business Ind Park Est Morristown Clondalkin Biller Ballymount, Co. Dublin Tallaght 24 Newbridge Dublin Date June 2015 Designed By PJK File Whole Site P9.sws Checked By CADS Storm W.7.3 (c) Micro Drainage Network Design Table Length Fall Slope (1:X) Area T.E. (mins) DWF k HYD SECT DIA o o o o o o o o o o o o o o o 225 Network Results Table Rain (mm/hr) T.C. (mins) US/IL E.Area E.DWF Foul Infil. Vel (m/s) CAP Flow

19 Burke Kavanagh Jenkins Burke Consulting Engineers Page 4 Consulting Unit G3 Engineers Housing Residential Development at 21 Calmount Cookstown Business Ind Park Est Clondalkin Morristown Biller Tallaght Ballymount, Co. Dublin24 Dublin Newbridge Date June 2015 Designed By PJK File Whole Site P9.sws Checked By CADS Storm W.7.3 (c) Micro Drainage Network Design Table Length Fall Slope (1:X) Area T.E. (mins) DWF k HYD SECT DIA o o o o o o o o o o o o o o o o 225 Network Results Table Rain (mm/hr) T.C. (mins) US/IL E.Area E.DWF Foul Infil. Vel (m/s) CAP Flow

20 Burke Kavanagh Jenkins Burke Consulting Engineers Page 5 Consulting Unit G3 Engineers Housing Residential Development at 21 Calmount Cookstown Business Ind Park Est Clondalkin Morristown Biller Ballymount, Co. Dublin Tallaght 24 Dublin Newbridge Date June 2015 Designed By PJK File Whole Site P9.sws Checked By CADS Storm W.7.3 (c) Micro Drainage Network Design Table Length Fall Slope (1:X) Area T.E. (mins) DWF k HYD SECT DIA o o o o o o o 600 Network Results Table Rain (mm/hr) T.C. (mins) US/IL E.Area E.DWF Foul Infil. Vel (m/s) CAP Flow

21 Attenuation Surface Water Tank Discharge Network Pipe Design Design

22 Kavanagh Burke Jenkins Burke Consulting Engineers Page 1 Unit Consulting G3 Engineers Residential Housing Development at Calmount 21 Cookstown Business Park Ind Est Morristown Clondalkin Biller Ballymount, Co. Dublin Tallaght 24 Newbridge Dublin Date June 2015 Designed By PJK File ATT Discharge Pipe.sws Checked By CADS Storm W.7.3 (c) Micro Drainage STORM SEWER DESIGN by the Modified Rational Method Network Design Table Length Fall Slope (1:X) Area T.E. (mins) DWF k HYD SECT DIA o o o o o 375 Network Results Table Rain (mm/hr) T.C. (mins) US/IL E.Area E.DWF Foul Infil. Vel (m/s) CAP Flow

23 Specification/Product Information for; a) Separators b) Silt Trap c) Flow Control Devices

24 SEPARATORS A RANGE OF FUEL/OIL SEPARATORS FOR PEACE OF MIND Let us help! Free professional site visit with friendly support and advice. helpingyou@klargester.com to make the right decision or call ADVANCED ROTOMOULDED CONSTRUCTION ON SELECTED MODELS!

25 Separators Surface water drains normally discharge to a watercourse or indirectly into underground waters (groundwater) via a soakaway. Contamination of surface water by oil, chemicals or suspended solids can cause these discharges to have a serious impact on the receiving water. The Environment Regulators, Environment Agency, England and Wales, SEPA, Scottish Environmental Protection Agency in Scotland and Department of Environment & Heritage in Northern Ireland, have published guidance on surface water disposal, which offers a range of means of dealing with pollution both at source and at the point of discharge from site (so called end of pipe treatment). These techniques are known as Sustainable Drainage Systems (SuDS). Where run-off is draining from relatively low risk areas such as car-parks and non-operational areas, a source control approach, such as permeable surfaces or infiltration trenches, may offer a suitable means of treatment, removing the need for a separator. Oil separators are installed on surface water drainage systems to protect receiving waters from pollution by oil, which may be present due to minor leaks from vehicles and plant, from accidental spillage. Effluent from industrial processes and vehicle washing should normally be discharged to the foul sewer (subject to the approval of the sewerage undertaker) for further treatment at a municipal treatment works. SEPARATOR STANDARDS AND TYPES A British (and European) standard (EN and 858-2) for the design and use of prefabricated oil separators has been adopted. New prefabricated separators should comply with the standard. SEPARATOR CLASSES The standard refers to two classes of separator, based on performance under standard test conditions. CLASS I Designed to achieve a concentration of less than 5mg/l of oil under standard test conditions, should be used when the separator is required to remove very small oil droplets. CLASS II Designed to achieve a concentration of less than 100mg/l oil under standard test conditions and are suitable for dealing with discharges where a lower quality requirement applies (for example where the effluent passes to foul sewer). Both classes can be produced as full retention or bypass separators. The oil concentration limits of 5 mg/l and 100 mg/l are only applicable under standard test conditions. It should not be expected that separators will comply with these limits when operating under field conditions. FULL RETENTION SEPARATORS Full retention separators treat the full flow that can be delivered by the drainage system, which is normally equivalent to the flow generated by a rainfall intensity of 65mm/hr. On large sites, some short term flooding may be an acceptable means of limiting the flow rate and hence the size of full retention systems. Get in touch for a FREE professional site visit and a representative will contact you within 5 working days to arrange a visit. helpingyou@klargester.com to make the right decision or call BYPASS SEPARATORS Bypass separators fully treat all flows generated by rainfall rates of up to 6.5mm/hr. This covers over 99% of all rainfall events. Flows above this rate are allowed to bypass the separator. These separators are used when it is considered an acceptable risk not to provide full treatment for high flows, for example where the risk of a large spillage and heavy rainfall occurring at the same time is small. FORECOURT SEPARATORS Forecourt separators are full retention separators specified to retain on site the maximum spillage likely to occur on a petrol filling station. They are required for both safety and environmental reasons and will treat spillages occurring during vehicle refuelling and road tanker delivery. The size of the separator is increased in order to retain the possible loss of the contents of one compartment of a road tanker, which may be up to 7,600 litres. SELECTING THE RIGHT SEPARATOR The chart on the following page gives guidance to aid selection of the appropriate type of fuel/oil separator for use in surface water drainage systems which discharge into rivers and soakaways. For further detailed information, please consult the Environment Agency Pollution Prevention Guideline 03 (PPG 3) Use and design of oil separators in surface water drainage systems available from their website. Klargester has a specialist team who provide technical assistance in selecting the appropriate separator for your application. 2

26 Is there risk of oil contaminating the drainage from the site? Yes Yes Yes Yes No Risk of infrequent light contamination and potential for small spills only, e.g. car park Yes Risk of regular contamination of surface water run off with oil and/or risk of larger spills, e.g. vehicle maintenance area, goods vehicle parking or vehicle manoevering 5 Drainage will also contain dissolved oils, detergents or degreasers such as vehicle wash water and trade effluents, e.g. industrial sites Fuel oils are delivered to and dispensed on site, e.g. retail forecourts Very low risk of oil contamination, e.g. roof water Yes Source control SuDS must be considered and incorporated where suitable Yes Yes Yes Separator not required If not suitable Bypass Separator with alarm required Class I if discharge to surface water 2,3 Class II if discharge to foul sewer 1 Full Retention Separator with alarm required Class I if discharge to surface water 2 Class II if discharge to foul sewer 1 Trade effluents must be directed to the foul sewer 1 It may need to pass through a separator before discharge to sewer for removal of free oils Full Retention Forecourt Separator with alarm required Class I if discharge to surface water 2 Class II if discharge to foul sewer 1,4 Clean water should not be passed through the separator unless the size of the unit is increased accordingly The use of SuDS should be considered at all sites and they should be incorporated where suitable. SuDS can be used to polish the effluent from these separators before it enters the environment 6 Source control SuDS should be considered where possible 1 You must seek prior permission from your local sewer provider before you decide which separator to install and before you make any discharge. 2 You must seek prior permission from the relevant environmental body before you decide which separator to install. 3 In this case, if it is considered that there is a low risk of pollution a source control SuDS scheme may be appropriate. 4 In certain circumstances, the sewer provider may require a Class 1 separator for discharges to sewer to prevent explosive atmospheres from being generated. 5 Drainage from higher risk areas such as vehicle maintenance yards and goods vehicle parking areas should be connected to foul sewer in preference to surface water. 6 In certain circumstances, a separator may be one of the devices used in the SuDS scheme. Ask us for advice. 3

27 Bypass APPLICATION Bypass separators are used when it is considered an acceptable risk not to provide full treatment, for very high flows, and are used, for example, where the risk of a large spillage and heavy rainfall occurring at the same time is small, e.g. Surface car parks. Roadways. Lightly contaminated commercial areas. PERFORMANCE Klargester were one of the first UK manufacturers to have separators tested to EN Klargester have now added the NSB bypass range to their portfolio of certified and tested models. The NSB number denotes the maximum flow at which the separator treats liquids. The British Standards Institute (BSI) tested the required range of Klargester full retention separators and certified their performance in relation to their flow and process performance assessing the effluent qualities to the requirements of EN Klargester bypass separator designs follow the parameters determined during the testing of the required range of bypass separators. Each bypass separator design includes the necessary volume requirements for: Oil separation capacity. Oil storage volume. Silt storage capacity. Coalescer. Class II separators are designed to achieve a concentration of 100mg/litre of oil under standard test conditions. FEATURES Advanced rotomoulded construction on selected models Compact and robust Require less backfill Tough, lightweight and easy to handle Light and easy to install. Class I and Class II designs. Inclusive of silt storage volume. Fitted inlet/outlet connectors. Vent points within necks. Oil alarm system available (required by EN and PPG3). Extension access shafts for deep inverts. Maintenance from ground level. GRP or rotomoulded construction (subject to model). To specify a nominal size bypass separator, the following information is needed:- The unit is designed to treat 10% of peak flow. The calculated drainage areas served by each separator are indicated according to the formula given by PPG3 NSB = A(m2). Flows generated by higher rainfall rates will pass through part of the separator and bypass the main separation chamber. Class I separators are designed to achieve a concentration of 5mg/litre of oil under standard test conditions. The calculated flow rate for the drainage area served. Our designs are based on the assumption that any interconnecting pipework fitted elsewhere on site does not impede flow into or out of the separator and that the flow is not pumped. The required discharge standard. This will decide whether a Class I or Class II unit is required. The drain invert inlet depth. Pipework type, size and orientation. SIZES AND SPECIFICATIONS UNIT FLOW PEAK FLOW DRAINAGE STORAGE UNIT UNIT DIA. ACCESS BASE TO BASE TO STANDARD MIN. INLET STANDARD NOMINAL RATE AREA (m 2 ) CAPACITY (litres) LENGTH SHAFT INLET INVERT OUTLET FALL ACROSS INVERT PIPEWORK SIZE SILT OIL DIA. INVERT DIA. NSBP NSBP NSBP NSBE NSBE NSBE NSBE NSBE NSBE NSBE NSBE NSBE NSBE Rotomoulded chamber construction GRP chamber construction * Some units have more than one access shaft diameter of largest shown. 4

28 PROFESSIONAL INSTALLERS Klargester Accredited Installers Experience shows that correct installation is a prerequisite for the long-lasting and successful operation of any wastewater treatment product. This is why using an installer with the experience and expertise to install your product is highly recommended. Services include : Site survey to establish ground conditions and soil types Advice on system design and product selection Assistance on gaining environmental consents and building approvals Tank and drainage system installation Connection to discharge point and electrical networks Waste emptying and disposal Discover more about the Accredited Installers and locate your local expert online. CARE & MAINTENANCE Kingspan Environmental Services Who better to look after your treatment plant than the people who designed and built it? Kingspan Environmental have a dedicated service division providing maintenance for wastewater products. Factory trained engineers are available for site visits as part of a planned maintenance contract or on a one-off call out basis. To find out more about protecting your investment and ensuring peace of mind, call us on: or visit us online: COMMERCIAL WASTEWATER SOLUTIONS BIODISC, BIOTEC & ENVIROSAFE HIGH PERFORMANCE SEWAGE TREATMENT SYSTEMS HILLMASTER PACKAGE PUMP STATIONS NEW BUILD & RETROFIT SOLUTIONS BELOW GROUND RAINWATER HARVESTING SYSTEMS ABOVE GROUND RAINWATER HARVESTING SYSTEMS PUMPSTOR24 PUMPING SYSTEMS STORMWATER ATTENUATION SYSTEMS OIL/WATER SEPARATORS BELOW GROUND STORAGE TANKS GREASE & SILT TRAPS Klargester UK: College Road North, Aston Clinton, Aylesbury, Buckinghamshire HP22 5EW Tel: +44 (0) Fax: +44 (0) Scottish Office: Tel: +44 (0) info@klargester.com Part of Ireland: Unit 1a, Derryboy Road, Carnbane Business Park, Newry, Co. Down BT35 6QH NI Tel : +44 (0) Fax: +44 (0) ROI Tel: Fax: info@klargester.ie Visit our website or our company website In keeping with Company policy of continuing research and development and in order to offer our clients the most advanced products, Kingspan Environmental reserves the right to alter specifications and drawings without prior notice. Issue No. 20: August 2014

29 TM Specialists in Wastewater Treatment & Stormwater Management Surface Water Treatment SUDs Protector The CDS Non Blocking screening technology is an innovative method of liquid / solid separation for Surface Water, Combined Sewer Overflows (CSO) and Foul Sewage Systems. SurfSep for Surface Water applications OverSep for Combined Sewer Overflow applications. The technology accomplishes high efficiency separation of settleable particulate matter and capture of floatable material. A unique feature of the CDS Technology is it s compact design. Both the SurfSep and OverSep are available as packaged systems, which can either be installed inside pre-cast concrete chamber rings, or complete BBA Approved Polyethylene Chambers unit. Applications Storm-water Treatment Combined Sewer Overflow Treatment Parking Area Run-Off Treatment Vehicle Service Yard Areas Pre-treatment for Wetlands, Ponds and Swales Rainwater Harvesting Pre-treatment for Oil Separators Pre-treatment for media and Ground In-filtration Systems

30 TM Surface Water System Rapid installation Primary features Effective: Capturing more than 95% of solid pollutants. Non-Blocking: Unique design takes advantage of indirect filtration and properly proportioned hydraulic forces that virtually makes the unit unblockable. Non-Mechanical: The unit has no moving parts and requires no mechanical devices to support the solid separation function. Low Maintenance Costs: The system has no moving parts and is fabricated of durable materials. Compact & Flexible: Design and size flexibility enables the use of various configurations. High Flow Effectiveness: The technology remains highly effective across a broad spectrum of flow ranges. Assured Pollutant Capture: All materials captured are retained during high flow conditions. Hydraulic Analysis In storm water applications, an analysis of the catchment in terms of its size, topography and land use will provide information for determining flow to be expected for various return periods. The SurfSep is designed for the flow that mobilizes the gross pollutants within the catchment. Since there are variations in catchment response due to region, land use and topography, it is recommended that the selection of flow to be treated will be for return periods of between 3 months and 1 year. Balancing the cost to the operator against the benefits to the environment Field evaluations to determine pollutant mobilization have found that the vast majority of pollutants are mobilized in flows that are well below the design capacity for the conveyance facility - typically known as the first flush. Therefore it is typical not to design the SurfSep models to process the conveyance system s maximum flow in order to achieve a very high level of pollutant removal. The added value benefit to the operator is reduced civil costs without compromising the benefits to the environment. How it works Water and pollutants enter the system and are introduced tangentially inside the separation chamber forming a circular flow motion. Floatables and suspended solids are diverted to the slow moving centre of the flow. Negatively buoyant solids settle out to an undisturbed sump chamber below, while the water passes countercurrently through the separation screen. Floatables remain at the water surface and retained within the screen. Safe & Easy Pollutant Removal: Extraction methods allow safe and easy removal of pollutants without manual handling. 2

31 Surface Water Treatment Systems Hydraulic Design Every application requires a detailed hydraulic analysis to ensure the final installation will perform to effect optimum solids separation without blocking the screen. After the design flow has been determined, the appropriate standard model can be selected. A selection table is provided on page 7. The Ultimate SUDs Protector There a four principal areas of proprietary SUDs technology; Infiltration Flow Control Storage/attenuation Treatment SurfSeps, although a common form of treatment are unique. When installed upstream of any proprietary SUDs technology, the SurfSep protects the receiving SUDs from fine solids and debris that would otherwise accumulate over time rendering the SUDs nonoperational, as the worst case. SurfSeps have been successfully installed in front of; Soakaways Infiltration Trenches Filters Wetlands Ponds and Water Features Detention and Retention Systems Oil Separators Create storage storage systems to remove fine solids and debris that would otherwise accumulate over time reducing the down stream effectiveness of downstream SUDs assets. Various independent field trials have shown that the SurfSep can remove high levels of Phosphates, Heavy Metals and PolyAramatic Hydrocarbons (PAH s) from the flow. Infiltration Detention & Retention Systems SurfSeps have been successfully installed in front of collection and attenuation SUDs to remove grit, fine solids and debris which accumulates in the SUDs leading to potential blockage of flow regulators resulting in increased Occupational Health & Safety risk during the treatment of blockages and during the periodic cleaning operations. Applications Rainwater Harvesting Road run off New Developments Motorways A / B Roads Local Roads Residential Industrial Commercial Purpose Removal of plastics, oil, grit, fine solids, organic and inorganic debris, from point source pollution. SurfSeps have been successfully installed in front of ground Infiltration systems to remove grit, fine solids and debris which accumulates in and around the SUDs causing visual degradation in the short term and accumulation of silt and grits leading to reduced volume in the long term. Studies have also shown that Heavy metals & PAH s accumulate within the SUDs over time before being released back to the environment resulting in elevated concentrations.

32 TM Flow Control Systems Flow Control Flow control is often required to reduce flooding of downstream sewer networks or receiving water courses. There are a number of ways to achieve this.the Hydroslide - Float controlled, constant flow regulator, as detailed below is ideally suited to the providing an efficient and reliable means of flow control. There are four types of standard Hydroslide flow regulators as pictured. 1) Mini 2) HydroLimiter 3) VS - Vertical Standard 4) Combi - self flushing, can be mounted on the dry or wet side of the flow chamber. Most applications can be dealt with using any of the four models to suit the flow. An accuracy of +/-5% is achievable. 1 2 Flow Control Technical Design Typical SurfSep installation The Hydroslide regulator does not affect the flow until the flow is approaching the set discharge limit, this allows all flow (the first flush) to be discharged to the sewer. Because the flow to the sewer can be optimised at it s maximum permitted capacity the attentuation/storage capacity can be reduced over other methods of flow control, thus giving cost savings in storage provision. This is best explained by looking at a single storm event and comparing the 3 flow regulation processes as was done independantly by WRc in the report titled REDUCING THE COST OF STORMWATER STORAGE, Report No. PT1052, March 1995.The chart below represents 50 l/s control and up to 4m of head.the area difference between the curves being the detention volume saving. Typically the volume saving when using a Hydroslide regulator is between 7% to 40% Representation of flow through an orifice Orifice Vortex Control Hydroslide Hydrolimiter Flow l/sec 60 4

33 Operation & Performance Performance Criteria Note: Screen apertures of 4.8 mm, 2.4 mm and 1.2 mm are available. The 4.8 and 2.4 mm screens are generally used for Surface Water applications, with foul applications using either 2.4 or 1.2 mm aperture units. Typical 1.2 mm aperture Performance shall remove all solids with a single dimension greater than 1.2 mm and positively contain those solids until the unit is cleaned. shall remove and positively contain 100 percent of all neutrally buoyant particles with a single dimension greater than 1.2 mm for all flow conditions to design capacity. shall remove and positively contain 100 percent of all floating trash and debris with a single dimension greater than 1.2 mm for all flow conditions to the design capacity. shall remove a minimum of 50 percent of oil and grease (as defined as the floating portion of total hexane extractable materials) for all flow conditions to the design capacity, without the addition of absorbents. shall provide the following minimum particle removal efficiencies (based on a specific gravity of 2.65): a) 100 percent of all particles greater than 1100 microns. b) 95 percent of all particles greater than 550 microns. c) 90 percent of all particles greater than 367 microns. d) 20 percent of all particles greater than 200 microns. Maintenance SurfSep maintenance can be site and drainage area specific. The installation should be inspected periodically to assure its condition to handle anticipated runoff. If pollutant loadings are known, then a preventive maintenance schedule can be developed based on runoff volumes processed. Since this is seldom the case we recommend; New Installations Check the condition of the installation after the first few events. This includes a visual inspection to ascertain that the unit is operating correctly and measuring the amount of deposition that has occurred in the unit.this may be achieved using a Dip Stick. Ongoing Operation For the first 12 months the installations sump full volume should be inspected monthly and recorded. When the inspection indicates that the sump full volume is approaching the top of the sump (base of screen) a cleanout should be undertaken. Cleaning Methods Eduction (Suction) Basket Removal Mechanical Grab Maintenance Cycle Minimum once per year. Depending on the pollutant load it may be necessary to maintain the installation more frequently. The operator shall be able to devise the most efficient maintenance schedule for any particular installation over a 12 month operating cycle.

34 TM SurfSep Dimensions SurfSep Dimensions SWI0404 SW0604 SW0606 SW0804 SW0806 SW0808 SWI010 SWI012 SWI015 A B C D E F G (dia) H

35 Selection Table - SurfSep Model Reference Hydraulic Peak Flow Rate l/s Drainage Area - Impermeable m 2 Chamber Diameter Internal Pipe Diameter SWI , / 225 SWI , SWI 0606 / , SWI 0606 / , SWI , SWI , SWI , SWI , SWI , / 750 SWI , / 750 In-Line SurfSep Units (SWI) * Proposed Peak Flow Rate for each model calculated using Rational Lloyd Davies with a rainfall intensity of 50mm/hr. For greater flows - special design / construction required. These units are used with in the drainage system in-line and are supplied as BBA Approved complete Polyethylene Chamber units from the selection table above. Off-Line SurfSep Units (SWO) These can be designed either using pre-cast concrete or specially designed Polyethylene chambers. Model Designation SurfSep models are firstly identified by the letters SW for Surface Water followed by a letter (I or O) representing the configuration (Inline or Offline). A four digit number representing the screen diameter and screen height then follows to give the standard model designation for a SurfSep screen for installation into standard commercially available pre-fabricated manhole chambers i.e SWI Example: SWI 0806 designates Surface Water Inline with a separation screen dia 0.8 m and screen height of 0.6m.

36 TM Surface Water Treatment Surface water system Attenuation tank Hydroslide flow control SurfSep Outfall Illustration: Detention & Retention Systems SurfSeps unit installed in front of attenuation tank / cellular storage system, to remove grit, fine sediments and floating debris which can accumulate within surface water systems. Hydroslide flow control regulating the discharge to the outfall. The Hydroslide can be supplied for installation in an insitu constructed chamber, or as a complete unit housed within a pre-fabricated polyethylene manhole chamber. Approved Suppliers * BBA - THIS CERTIFICATE RELATES TO PIPEX UNIVERSAL MANHOLES AND ACCESS CHAMBERS, WHICH ARE MANUFACTURED FROM WELDED POLYPROPYLENE. This Certificate covers the use of the manholes and chambers for drain and sewer applications where they are used for maintenance to depths of 6 mtrs. If you would like more information please contact: CDS Technologies is a multi disciplined, international, company offering a comprehensive product range of; wastewater treatment technologies and processes, and stormwater management solutions for attenuation, infiltration, flow control and overflow treatment. CDS have an established network of Distributors and Representatives. Further information can be found on our website Alternatively please contact our approved supplier detailed left. CDS Technologies Limited 2005/2006 All rights reserved. Issue 1001/

37 Hydro-Brake Flow Control stormwater Modelling Guide Overview Unit Selection Design Guide Hydro-Brake Flow Controls restrict the flow in surface/storm water or foul/combined sewer systems by inducing a vortex flow pattern in the water passing through the device, having the effect of increasing back-pressure. STH Range of Hydro-Brake Flow Controls Their hydrodynamic rather than physical restriction based operation provides flow regulation whilst maintaining larger clearances than most other types of flow control, making them less susceptible to blockage. Their unique S -shaped headflow characteristic also enables them to pass greater flows at lower heads, which can enable more efficient use of upstream storage facilities. This document provides guidance relating to the selection and use of Hydro-Brake Flow Controls for use in surface/storm water and foul/combined sewer systems. The information provided here is intended for the purposes of general guidance only - individual application requirements may differ. If in doubt, or to enquire about new product additions, please contact HRD Technologies Ltd. See back cover for details. Hydraulic Characteristics and Specification Hydro-Brake Flow Controls should be selected such that the duty/design flow is not exceeded at any point on the head-flow curve, see illustration right. If this is not achievable using the initially selected unit, it may be appropriate to select an alternative option (see selection guidance overleaf). (a) (b) Kick-Flo Point Flush-Flo Point While the primary aim of a flow control is to provide a particular flow rate at a given upstream head (giving a design/duty point), it is important to note that secondary opportunities, such as potential for optimised storage use, derive from consideration of the full hydraulic characteristic. It is therefore important to ensure that the same flow control, or one confirmed to provide equivalent Hydraulic Head (a) (b) Duty Design Point Duty Design Flow hydraulic performance, is implemented in any final installation. Pass Forward Flow Typical Hydro-Brake Head Versus Flow Characteristics To ensure correct implementation a multiple design-point specification, defining the main hydraulic features of the selected flow control, can be provided by HRD Technologies Ltd. This should include at least the following information: outlet size and model of Hydro-Brake Flow Control definition of the duty/design point (head and flow) definition of the Flush-Flo point (head and flow) definition of the Kick-Flo point (head and flow) To ensure that a drainage system performs as designed, it is strongly recommended that this information is reproduced on any technical specifications. Telephone: +353 (0) turning water around...

38 STH Type Hydro-Brake Flow Control with BBA Approval Now included in WinDes W.12.6! The new STH type Hydro-Brake Flow Control range has a unique head / discharge performance curve which introduces a very important feature - the Switch-Flo Point. This point illustrates the unique performance feature of the STH range which can lead to further savings in upstream storage, whilst also enabling increased inlet / outlet size to further reduce the risk of blockage. (a) (b) (c) Kick-Flo Point Switch-Flo Point Flush-Flo Point Kick-Flo (a) - the point at which the vortex has initiated and at which the curve begins to return back to follow the orifice curve and reach the same design point or desired head / flow condition. Hydraulic Head Pass Forward Flow Typical STH Head Versus Flow Characteristics (a) (b) (c) Design Point NEW Switch-Flo (b) - marks the transition between the Kick-Flo and Flush-Flo, from vortex initiation to stabilisation. This point adds a new layer of resolution to the Hydro-Brake curve that has implications to upstream storage savings. Flush-Flo (c) - the point at which the vortex begins to initiate and have a throttling effect. This point on the Hydro-Brake curve is usually much nearer to the maximum design flow (Design Point), than other vortex flow controls leading to more water passing through the unit during the earlier stages of a storm, thus reducing the amount of water that needs to be stored upstream. STH Range of Hydro-Brake Flow Controls The STH Hydro-Brake Flow Control is the only vortex flow control available today that has been given the prestigious BBA Approval Certificate. The BBA assessment procedure entails rigorous assessment of production and manufacturing standards, and confirms that the hydraulic performance of the Hydro-Brake Flow Control matches the data given to designers by HRD Technologies with their head / discharge curves. A worked example showing the steps to model a Hydro-Brake Flow Control and associated Stormcell Storage System within Micro Drainage WinDes is available on our website: Take a Look at Our New Stormwater Web Resource Provide the following Flow Control Devices: Refer to Drainage Layout Drawing (D1493-D1-2-PL5 and D1493-D4-PL5) a) Limit Flow to Q2: l/sec for interaction b) Balance of of existing Q30: surface 23.9 l/sec water flows with proposed. Max Discharge from site: Q30: l/sec Engineering Nature s Way is a brand new resource for people working with Sustainable Drainage and flood management in the UK. The site provides an opportunity to share news, opinion, information and best practice for people working in local and central Government; developers, consulting engineers and contractors. Do you have something to share? We would be delighted to receive your contributions. turning water around... This information is for guidance only and not intended to form part of a contract. HRD Technologies Ltd pursues a policy of continual development and reserves the right to amend specifications without prior notice. Equipment is patented in countries throughout the world. HRD Technologies Ltd Tootenhill House Rathcoole Co. Dublin Ireland Tel: +353 (0) Fax: +353 (0) HRD Technologies Ltd is a subsidiary of Hydro International plc ABCDEF HRD Technologies Ltd 2011 IRL HBFC Modelling Guide A1211

39 Foul Sewer Network Design

40 Kavanagh Burke Jenkins Burke Consulting Engineers Page 1 Unit Consulting G3 Engineers Residential Development at Calmount 21 Cookstown Business Ind Park Est Morristown Clondalkin Biller Ballymount, Tallaght Co. Dublin24 Newbridge Dublin Date Designed By PJK File FOUL Whole Site PL9.fws Checked By CADS Foul W.7.3 (c) Micro Drainage FOUL SEWERAGE DESIGN Network Design Table Industrial Flow (l/s/ha) 0.00 O'flow Setting (*Foul only) 0 Industrial Peak Flow Factor 0.00 Infiltration % 0 Calculation Method BS 8301 Minimum Backdrop Height Frequency Factor 0.00 Depth from Soffit to G.L Domestic (l/s/ha) 0.00 Min Vel. (m/s - Auto Design Only) 0.75 Domestic Peak Flow Factor 0.00 Min Slope (1:X - Optimisation) 500 Designed with Level Inverts Network Design Table Length Fall Slope (1:X) Area Units DWF k HYD SECT DIA o o o o o o o o o o o 225 Network Results Table US/IL E.Area E.DWF E.Units Infil. P.Dep P.Vel (m/s) Vel (m/s) CAP Flow

41 Kavanagh Burke Jenkins Burke Consulting Engineers Page 2 Unit Consulting G3 Engineers Residential Development at Calmount 21 Cookstown Business Ind Park Est Morristown Clondalkin Biller Ballymount, Co. Dublin Tallaght 24 Newbridge Dublin Date Designed By PJK File FOUL Whole Site PL9.fws Checked By CADS Foul W.7.3 (c) Micro Drainage Network Design Table Length Fall Slope (1:X) Area Units DWF k HYD SECT DIA o o o o o o o o o o o o o o o o o 225 Network Results Table US/IL E.Area E.DWF E.Units Infil. P.Dep P.Vel (m/s) Vel (m/s) CAP Flow

42 Kavanagh Burke Jenkins Burke Consulting Engineers Page 3 Unit Consulting G3 Engineers Residential Development at Calmount 21 Cookstown Business Ind Park Est Clondalkin Morristown Biller Ballymount, Co. Dublin Tallaght 24 Dublin Newbridge Date Designed By PJK File FOUL Whole Site PL9.fws Checked By CADS Foul W.7.3 (c) Micro Drainage Network Design Table Length Fall Slope (1:X) Area Units DWF k HYD SECT DIA o o o o o o o o o o o o o o o o 225 Network Results Table US/IL E.Area E.DWF E.Units Infil. P.Dep P.Vel (m/s) Vel (m/s) CAP Flow

43 Kavanagh Burke Jenkins Burke Consulting Engineers Page 4 Unit Consulting G3 Engineers Residential Development at Calmount 21 Cookstown Business Ind Park Est Morristown Clondalkin Biller Ballymount, Co. Dublin Tallaght 24 Newbridge Dublin Date Designed By PJK File FOUL Whole Site PL9.fws Checked By CADS Foul W.7.3 (c) Micro Drainage Network Design Table Length Fall Slope (1:X) Area Units DWF k HYD SECT DIA o o o o o o o o o o o o o o 225 Network Results Table US/IL E.Area E.DWF E.Units Infil. P.Dep P.Vel (m/s) Vel (m/s) CAP Flow

44 Kavanagh Burke Jenkins Burke Consulting Engineers Page 5 Unit Consulting G3 Engineers Residential Development at Calmount 21 Cookstown Business Ind Park Est Morristown Clondalkin Biller Ballymount, Tallaght Co. Dublin24 Newbridge Dublin Date Designed By PJK File FOUL Whole Site PL9.fws Checked By CADS Foul W.7.3 (c) Micro Drainage Network Design Table Length Fall Slope (1:X) Area Units DWF k HYD SECT DIA o o o o o o o 300 Network Results Table US/IL E.Area E.DWF E.Units Infil. P.Dep P.Vel (m/s) Vel (m/s) CAP Flow

45 Watermain Head Loss: Existing Patrick Byrne development is served from a 150Ø watermain. The subject application for Retention involves 40No. Houses. IN addition to these 40 houses a further 160 houses is proposed. A schematic layout of the watermain arrangement is shown below: +GL: Existing 150Ø watermain constructed by others in Phase 1 +GL: Proposed 1 st loop of watermain 680m long. Proposed No. of houses: 100 +GL: Proposed 2 nd loop of watermain 550m long. Proposed No. of houses: 100 Pipe Ø = 150mm Material: MoPVC Flow rate 1 st loop 100 houses x 4 people per house x 150l/p/day = 60,000 l/day At an effective usage time 16h per day: 60000l/(16 x 3600s) = 1.04 l/s is the flow rate.

46 Considering 200 houses when including the 2 nd loop the flow rate will be 2.1 l/s. Regarding static head: All proposed houses will be lower than the water source. Calculate the Dynamic Friction Loss due to the flow in the watermain: Pipe length: 680m + 550m = 1230m; Pipe Ø = 150mm; Roughness factor = 0.01k/mm Fresh water line: Assume flow of 10l/sec (Conservative peak flow) Friction Loss calculated by Colebrook Equation through computer software: 2.6m Where 1bar 10m H2O then 2.6m 0.3 bar

47

48

49 Appendix A

50 Burke Kavanagh Jenkins Burke Consulting Engineers Page 1 Consulting Unit G3 Engineers Housing Residential Development at 21 Calmount Cookstown Business Ind Park Est Clondalkin Morristown Biller Ballymount, Co. Dublin Tallaght 24 Newbridge Dublin Date June 2015 Designed By PJK File Phase 1 FLow P5 CCF applied t... Checked By CADS Storm W.7.3 (c) Micro Drainage STORM SEWER DESIGN by the Modified Rational Method Global Variables Location - Scotland & Ireland Return Period (years) 1 Volumetric Runoff Coeff M Infiltration % 0 Ratio R 0.29 Minimum Backdrop Height Maximum Rainfall (mm/hr) 50 Depth from Soffit to G.L Foul Sewage (l/s/ha) 0.00 Min Vel. (m/s - Auto Design Only) 0.80 O'flow Setting (*Foul only) 0 Min Slope (1:X - Optimisation) 500 Designed with Level Soffits Phase 1 (by others) Existing Storm Water Network Flows Analysis. Network Design Table Length Fall Slope (1:X) Area T.E. (mins) DWF k HYD SECT DIA o o o o o o o o o o o o 300 Network Results Table Rain (mm/hr) T.C. (mins) US/IL E.Area E.DWF Foul Infil. Vel (m/s) CAP Flow

51 Burke Kavanagh Jenkins Burke Consulting Engineers Page 2 Consulting Unit G3 Engineers Housing Residential Development at 21 Calmount Cookstown Business Ind Park Est Clondalkin Morristown Biller Tallaght Ballymount, Co. Dublin24 Dublin Newbridge Date June 2015 Designed By PJK File Phase 1 FLow P5 CCF applied t... Checked By CADS Storm W.7.3 (c) Micro Drainage Network Design Table Length Fall Slope (1:X) Area T.E. (mins) DWF k HYD SECT DIA o o o o o o o o o o o o o o o o o 225 Network Results Table Rain (mm/hr) T.C. (mins) US/IL E.Area E.DWF Foul Infil. Vel (m/s) CAP Flow

52 Kavanagh Burke Jenkins Burke Consulting Engineers Page 3 Unit Consulting G3 Engineers Residential Housing Development at Calmount 21 Cookstown Business Ind Park Est Morristown Clondalkin Biller Ballymount, Tallaght Co. Dublin24 Newbridge Dublin Date June 2015 Designed By PJK File Phase 1 FLow P5 CCF applied t... Checked By CADS Storm W.7.3 (c) Micro Drainage Network Design Table Length Fall Slope (1:X) Area T.E. (mins) DWF k HYD SECT DIA o o o o o o o o o o o o o o o 450 Network Results Table Rain (mm/hr) T.C. (mins) US/IL E.Area E.DWF Foul Infil. Vel (m/s) CAP Flow

53 Kavanagh Burke Jenkins Burke Consulting Engineers Page 4 Unit Consulting G3 Engineers Housing Residential Development at Calmount 21 Cookstown Business Ind Park Est Clondalkin Morristown Biller Ballymount, Tallaght Co. Dublin24 Dublin Newbridge Date June 2015 Designed By PJK File Phase 1 FLow P5 CCF applied t... Checked By CADS Storm W.7.3 (c) Micro Drainage Network Design Table Length Fall Slope (1:X) Area T.E. (mins) DWF k HYD SECT DIA o 450 Network Results Table Rain (mm/hr) T.C. (mins) US/IL E.Area E.DWF Foul Infil. Vel (m/s) CAP Flow

54 Appendix B

55 Kavanagh Burke Consulting Engineers Unit G3 Calmount Park Ballymount Dublin 12 5 June 2018 Dear Sir/Madam, Letter Ref: CUST17776 Rev 1 Re: CUST17776 Revised pre-connection enquiry Subject to contract Contract denied Connection for Strategic Housing Development of 320no. (Revised from 193 Units) houses & Creche at Station Road, Newbridge Irish Water has reviewed your pre-connection enquiry in relation to water and wastewater connections at Morristownbiller and Cornellscourt, Station Road, Newbridge, Co Kildare (the development). Based upon the details you have provided with your pre-connection enquiry and on the capacity currently available as assessed by Irish Water, we wish to advise you that, subject to a valid connection agreement being put in place and the conditions listed below, your proposed connection to the Irish Water network can be facilitated. Strategic Housing Development Irish Water notes that the scale of this development dictates that it is subject to the Strategic Housing Development planning process. Therefore: A. In advance of submitting your full application to An Bord Pleanala for assessment, you must have reviewed this development with Irish Water and received a Statement of Design Acceptance in relation to the layout of water and wastewater services. B. You are advised that this correspondence does not constitute an offer in whole or in part to provide a connection to any Irish Water infrastructure and is provided subject to a connection agreement being signed and appropriate connection fee paid at a later date. C. In advance of submitting this development to An Bord Pleanala for full assessment, the Developer is required to have entered into a Project Works Services Agreement (PWSA) to deliver investigations to confirm the available capacity and to determine the full extent of any water or wastewater upgrades which may be required to be completed to Irish Water infrastructure. D. The timelines and phasing of the development and any wastewater upgrades will be subject to the PWSA investigations. E. Provision of a Deed of Easement all foul and water pipelines in the development and protection of the existing 300mm diameter foul sewer will be a requirement of the connection agreement. A connection agreement can be applied for by completing the connection application form available at Irish Water s current charges for water and wastewater connections are set out in the Water Charges Plan as approved by the Commission for Regulation of Utilities.

56 Should you wish to have any of the above progressed by Irish Water or if you have any further questions, please contact Fionán Ginty from the design team on or For further information, visit Yours sincerely, Maria O Dwyer Connections and Developer Services

57 Letter Ref: CDS Statement of Design Acceptance Kavanagh Burke Consulting Engineers Unit G3 Calmount Park Ballymount Dublin June 2018 Dear Sir/Madam, Re: 320 no. dwellings & 1 no. crèche at Morristownbiller & Cornellscourt, Station Road, Newbridge, Co. Kildare Irish Water has reviewed your Design Submission in relation to water and wastewater connections at Station Road, Newbridge, Co. Kildare. Based upon the details you have provided with your Design Submission, including but not limited to the documents referenced below, Irish Water has no objection to the proposals included in your Design Submission. Document Title & Revision: 1. D D1-1 Rev PL5 2. D D1-2 Rev PL5 3. D D1-3 Rev PL5 4. D D10 Rev PL4 You are advised that this correspondence does not constitute an offer in whole or in part to provide a connection to any Irish Water infrastructure and is provided subject to a connection agreement being signed at a later date. If not already done so, a connection agreement can be applied for by completing the connection application form available at Irish Water s current charges for water and wastewater connections are set out in the Water Charges Plan as approved by the Commission for Regulation of Utilities (CRU). This Statement of Design Acceptance does not relieve you or your designer(s) of responsibility for the proposals and it remains a requirement to comply fully with the Irish Water Codes of Practice and Standard Details. Ultimate responsibility (including, but not limited to any losses, costs, demands, damages, actions, expenses, negligence, and claims) for the detailed design, construction and provision of such pipes and related infrastructure shall rest entirely with the Customer, his/her designer(s), contractor(s), or other related party. If you have any further questions, please contact Noeen Dineen from the design team on or ndineen@water.ie. For further information, visit Yours sincerely, Maria O Dwyer Connections and Developer Services