drainage strategy for michael drayton school extension
TRANSCRIPT
Issue 01
25/06/18
Drainage Strategy
for
Michael Drayton School Extension
Warwickshire County Council
Drainage Strategy
MJC/KJD/171638/17-2 Reports/Drainage Strategy - Issue 01
Document History Issue Date Comment Author Chk’d 01 25/06/18 First Issue KJD JSW
Drainage Strategy
MJC/KJD/171638/17-2 Reports/Drainage Strategy - Issue 01
Contents
1.0 Introduction ....................................................................................................... 1
2.0 Site Setting ........................................................................................................ 1
Site Description and Location 1
Proposed Development 1
3.0 Existing Drainage .............................................................................................. 2
Foul Drainage 2
Surface Water 2
Possible Seven Trent Surface Water Sewer 2
4.0 Proposed Drainage ............................................................................................ 2
Proposed Foul Drainage 2
Proposed Surface Water 3
5.0 Seven Trent Development Enquiry Application ............................................. 4
6.0 Micro Drainage Windes Calculations ............................................................... 4
7.0 Rainwater Harvesting........................................................................................ 4
8.0 Pollution Control ............................................................................................... 4
Appendix A
Existing and proposed peak foul flow calculations in accordance with BS EN 12506-2
Appendix B
Proposed Phase One Foul Drainage Drawings
Appendix C
Existing green field run off rate for the development
Appendix D
Proposed phase two surface water drainage drawings
Appendix E
Surface water Miro Drainage Windes Calculations
Drainage Strategy
1 MJC/KJD/171638/17-2 Reports/Drainage Strategy - Issue 01
1.0 Introduction
Pick Everard have been appointed as to undertake the civil engineering design elements for
Michael Drayton Junior School in Nuneaton. This drainage strategy outlines the current
drainage systems on the site and how these will be affected by the project. This document
will also provide a guide of the proposed drainage for development.
2.0 Site Setting
Site Description and Location
The application site runs to 26,735m² / 2.764ha (6.6acres) and is located to the northern
side of Hartshill, Warwickshire, approximately 6km from Nuneaton. The site is bounded to
the east by the residential properties fronting Church Road, the main through road running
north out of Hartshill. The site is approximately centred on National Grid Reference
(NGR) 432555, 293977.
Proposed Development
It is proposed to construct a number of single storey extensions to the existing school and
undertake refurbishment of various sections. The project will be built in 2 phases. Phases
1includes the construction of a hall extension and various enabling works and phase 2
involves an extension that will create 4 new classrooms.
The proposed development is shown in Figure 2, below;
Figure 1 Proposed Development
Phase One Details
Phase one will include a small hall extension, approximately 33m2, to the front of the
school. The footprint of the extension will be constructed on existing hardstanding. The
hall construction works requires the existing foul drainage to be diverted around the
proposed hall footprint. Phase one also includes the enabling works for the temporary
Phase One Hall
Extension
Phase Two Year 4 Class Room Extension
Phase Two Year 5 and 6 Class Room Extensions
Temporary Class Room Location
Drainage Strategy
2 MJC/KJD/171638/17-2 Reports/Drainage Strategy - Issue 01
building. The temporary building will be constructed on the existing playground east of the
site in front of the year 4 classrooms.
Phase Two Details
Phase two will include 3 separate extensions to class rooms to the east of the site. The
largest of which will house 2 year 4 class rooms, a small toilet block, a staff room, group
working room and a reprographic centre. The total footprint new class room extensions
will be approximately 406m2.
The development of the year 5 and 6 classrooms will require the existing surface water
drainage to be diverted around the proposed footprint of the building.
3.0 Existing Drainage
A below ground utilities survey was carried out by Midlands Survey in May 2018. The
survey identified the existing on site drainage systems and services. A CCTV survey was
also carried out by Midlands Survey. It was found that the school has a separate surface
water and foul drainage system. Furthermore, the CCTV investigation found that most of
the drainage pipes are constructed from Pitch Fibre. Pitch fibre is a material common
construction material commonly associated with asbestos.
Foul Drainage
The existing foul drainage flows, by gravity, to the front of the school and discharges into
the public sewer through the main school gate. The existing peak foul sewage flow of 4.1 l/s
has been calculated in accordance with BS EN 12506-2 based upon the number of wet
appliances to be installed in the building. Appendix A
Surface Water
A series of rain water pipes and land drains collect the surface water and discharges it in to
the surface water network. Similar to the foul the surface water drainage discharges from
site through the main school gate, to the north west.
Possible Seven Trent Surface Water Sewer
The topographical and CCTV survey found that there is a 300mm diameter surface water
pipe, possibly owned by Seven Trent Water, running underneath the existing building. The
new year 6 class rooms extension will be built over this pipe. A pre-development enquiry
has been submitted and the response will detail any Seven Trent owned sewers on site.
This will help Pick Everard to understand if a build over agreement is required.
4.0 Proposed Drainage
Proposed Foul Drainage
Due to the extent of the hall extension and associated foundations the foul and surface
water pipes will need to be diverted around the development. This is included within Phase
one. Phase one will also include the constructing of the permeant foul drainage which will
serve the small toilet block located within the new year 4 class rooms. The toilet block
within the extension will consist of 4 toilets and 4 sinks. The proposed peak foul sewage
Drainage Strategy
3 MJC/KJD/171638/17-2 Reports/Drainage Strategy - Issue 01
flow of 2.5l/s has been calculated in accordance with BS EN 12506-2 based upon the
number of wet appliances to be installed in the building, appendix A.
Before the occupation of the new extension a temporary building will be constructed and
will house no more than 4 toilets and 4 sinks. The foul drainage from the temporary
building will connect into the new permeant drainage to enable the school to drain the foul
water without installing a temporary septic tank or pump out the toilets with a tanker. This
will help to decrease the disturbances to the school during teaching hours.
The Phase one foul drainage drawings can be found in Appendix B
Proposed Surface Water
Infiltration testing
Infiltration testing was undertaken on 20 November 2017 by Nicholls Colton Group. The
tests were carried out in accordance with BRE digest 365. The initial feedback from
Nicholls Colton has proved that the ground is not suitable for drainage by infiltration as the
water level in the three trial pits did not decrease discernibly over a period of four to six
hours. Pick Everard are awaiting the final report.
Discharge Rates
The phases 2 development will increase the hardstanding from approximately 2750m2 to
3076m2 which is an increase of 326 m2. Warwickshire County Council Strategic Flood Risk
Assessment (SFRA) states “Surface water runoff from all new developments should be
attenuated to the Greenfield runoff rate for equivalent rainfall events up to and including the 1 in
100 year plus climate change.” The greenfield run off rate has been calculated using the UK
SUDs Greenfield Runoff Calculator. The catchment area for the proposed site was set to
0.1ha as this is the smallest area that could be inputted. The results are included in
Appendix C and summarised in Table 1 below.
Qbar (l/s) 0.47
1 in 1 year (l/s) 0.39
1 in 30 year (l/s) 0.93
1 in 100 year (l/s) 1.2 Table 1 Proposed Greenfield Run-off Rate Calculations
As restricting the run-off to the greenfield rates given above would require the flow to be
controlled to a rate well below the minimum practical piped controlled discharge of 5l/s.
The surface water discharge from the year 4 extension will be reduced to no more than
5l/s during the 1 in 100 year + 40% climate change storm.
Proposed Surface water Drainage System
The hall extension and year 5 and year 6 classrooms will be constructed on existing
hardstanding. Therefore, the surface water run off will discharge into the existing drainage
via rain water down pipes and land drains.
The existing carpark will be extended by 76m2 to accommodate correctly sizes disabled
spaces and 5 new parking spaces. The surface water drainage from new carpark extension
will discharge in to the existing drainage system.
The year 4 class room extension and proposed footpath will be constructed on existing
hardstanding and existing playing fields. The surface water discharge from the new class
Drainage Strategy
4 MJC/KJD/171638/17-2 Reports/Drainage Strategy - Issue 01
room and footpath will be collected in a series of rain water pipes and land drains and will
discharge in to a new length of 300mm dia pipe. An orifice plate will be placed within the
downstream manhole of the 300mm dia pipe. The orifice plate will restrict the surface
water discharge to no more than 5 l/s as it discharges in to the existing drainage system.
The proposed surface water drainage can be found in the Appendix D
5.0 Seven Trent Development Enquiry Application
A development application has been submitted to Seven Trent Water on the 18 of June
2018. Pick Everard are awaiting the response.
6.0 Micro Drainage Windes Calculations
The proposed drainage network has been input into WinDes drainage simulation software.
The 1 in 1 year, 1 in 2 year, 1 in 30 year and 1in 100 + 40% climate change events have
been simulated. The Windes Calculations can be found in Appendix E
7.0 Rainwater Harvesting
Rainwater harvesting has been considered but deemed not economically viable due to the
small number of new toilets in the proposed development.
8.0 Pollution Control
The Environment Agency sets out guidelines for many different pollution issues, pollution
prevention guidelines (PPG). PPG3 sets out guidelines for the use and design of oil
separators in surface water drainage systems. It states that “car parks typically larger than
800m2 in area or for 50 or more car parking spaces” will require a separator. This
redevelopment project is too small to require an oil interceptor.
Drainage Strategy
MJC/KJD/171638/17-2 Reports/Drainage Strategy - Issue 01
Appendix A
Existing and proposed peak foul flow calculations in accordance with
BS EN 12506-2
21/06/2018
BUILDING FOUL DRAINAGE BS EN 12506-2:2000 - SYSTEM III
Scheme: Michael Drayton
Ref: 171638
Building:
K
Frequency Factor: Frequent 0.7 e.g. Hospital, school, restaurant, hotel
Discharge
Appliance Unit (DU) No. Sum DUs Flow
(l/s)
I had a look Kerry
Basin 0.3 42 12.6 2.485
Sink 0.6 15 9 2.100
Shower 0.4 8 3.2 1.252
Urinal 0.4 17 6.8 1.825
Domestic Washing Machine 0.6 2 1.2 0.767
Dishwasher 0.2 1 0.2 0.313
Other:
Sum 33 4.02 l/s
Exsiting Foul Loading
21/06/2018
BUILDING FOUL DRAINAGE BS EN 12506-2:2000 - SYSTEM III
Scheme: Michael Drayton
Ref: 171638
Building:K
Frequency Factor: Frequent 0.7 e.g. Hospital, school, restaurant, hotel
Discharge
Appliance Unit (DU) No. Sum DUs Flow
(l/s)
I had a look Kerry
WC 1.8 6 10.8 2.300
Basin 0.3 6 1.8 0.939
Other:
Sum 12.6 2.48 l/s
Proposed Foul Loading
X001KJD-171638-17-1 Foul Load.xlsx 21/06/2018
Drainage Strategy
MJC/KJD/171638/17-2 Reports/Drainage Strategy - Issue 01
Appendix B
Proposed Phase One Foul Drainage Drawings
WAR007-PE-XX-ZZ-DR-C-0500_Proposed Drainage Layout - Phase One - Sheet 1 of 2_171638
WAR007-PE-XX-ZZ-DR-C-0501_ Proposed Drainage Layout - Phase One - Sheet 2 of 2_171638
100035
00
Year 4 class room extenstion
Existing School building
FWMH03
CL = TBC
IL = 140.213m AOD
FWMH01
CL = TBC
IL = 140.413
Proposed Foul Drainage to connect into the existing
drainage which flows the the public sewer.
CL = 140.860m AOD
IL = 139.580m AOD
FWMH02
CL = TBC
IL = 140.341m AOD
100mm dia Pipes
to SVP
1:40 Gradient
KEY:
- Proposed foul water sewer
- Proposed foul water manhole (1200mmØ PCC)
- Proposed foul water inspection chamber (475mmØ
- Proposed foul water internal gully (with trap)
- Proposed foul water gully (trapless)
- Proposed foul water stub pipe
- Existing foul drainage
-Existing foul drainage to be abandoned
G
IG
st
KEY:
- Proposed surface water sewer
- Proposed surface water manhole
(1200mmØ PCC)
- Proposed surface water inspection
chamber (475mmØ PPIC)
- Proposed surface water gully
- Proposed rainwater downpipe
- Proposed channel drain
- Existing surface water pipe
G
rwp
A1
Draft Planning IssueP01 15.06.18 KJDRevision Date Drn Chk
CDM - RESIDUAL HAZARDS
1
2
3 etc.
Further possible control measures have been identified within the Design RiskAssessments which may help to mitigate these and other identified risksfurther during the construction / maintenance process.
S0 - Work in Progress
Client
Job No.
Suitability Status
Drawing Number
@ A1Scale
Project
Rev
NO DIMENSIONS TO BE SCALED FROM THIS DRAWING
This drawing is issued for the sole and exclusive use of the intended recipient and issubject to copyright in favour of Pick Everard. Pick Everard does not accept anyresponsibility or liability whatsoever for its use by a person other than the intendedrecipient.
Size
Drawing Title
T 0345 045 0050 www.pickeverard.co.uk
CDM - RESIDUAL HAZARDS The following are considered to be significant risksrelevant to this drawing, which could not be fully mitigated or removed throughdesign:
Project Code - Originator - Zone - Level - Type - Role - Number
171638 P02
Warwickshire County Council
Michael Drayton School
Proposed Drainage LayoutPhase OneSheet 2 of 2
1:50
WAR7-PEV-XX-ZZ-DR-C-0501
Planning IssueP02 25.06.18 KJD JSW
A
1
A
1
A
1
A
1
A
1
A
1
A
1
A
1
A
1
A
1
A
1
A
1
A
1
Existing Surface water RWP to be removed
Existing Surface pipe to be retained
Divert existing foul sewer
around the new extension
FWMH04
CL=TBC
IL= 139.270m
FWMH05
CL = TBC
IL = 139.120m
FWMH06
CL = TBC
IL= 139.099m AOD
EXMHF4
CL = TBC
IL = 139.340m
EXMHF3
CL = m
IL = 138.980m
Assumed 100mm dia Pipe
1:75 Gradient
From historical drawings
EXMHS11
CL = TBC
IL = 139.640m
EXMHS10
CL = TBC
IL = 139.213m
Invert of Existing SW
Approx 139.441m AOD
Invert of Existing SW
Approx 139.207m AOD
KEY:
- Proposed foul water sewer
- Proposed foul water manhole (1200mmØ PCC)
- Proposed foul water inspection chamber (475mmØ
- Proposed foul water internal gully (with trap)
- Proposed foul water gully (trapless)
- Proposed foul water stub pipe
- Existing foul drainage
-Existing foul drainage to be abandoned
G
IG
st
KEY:
- Proposed surface water sewer
- Proposed surface water manhole
(1200mmØ PCC)
- Proposed surface water inspection
chamber (475mmØ PPIC)
- Proposed surface water gully
- Proposed rainwater downpipe
- Proposed channel drain
- Existing surface water pipe
G
rwp
A1
Draft Planning IssueP01 15.06.18 KJDRevision Date Drn Chk
CDM - RESIDUAL HAZARDS
1
2
3 etc.
Further possible control measures have been identified within the Design RiskAssessments which may help to mitigate these and other identified risksfurther during the construction / maintenance process.
S0 - Work in Progress
Client
Job No.
Suitability Status
Drawing Number
@ A1Scale
Project
Rev
NO DIMENSIONS TO BE SCALED FROM THIS DRAWING
This drawing is issued for the sole and exclusive use of the intended recipient and issubject to copyright in favour of Pick Everard. Pick Everard does not accept anyresponsibility or liability whatsoever for its use by a person other than the intendedrecipient.
Size
Drawing Title
T 0345 045 0050 www.pickeverard.co.uk
CDM - RESIDUAL HAZARDS The following are considered to be significant risksrelevant to this drawing, which could not be fully mitigated or removed throughdesign:
Project Code - Originator - Zone - Level - Type - Role - Number
171638 P02
Warwickshire County Council
Michael Drayton School
Proposed Drainage LayoutPhase OneSheet 1 of 2
1:75
WAR7-PEV-XX-ZZ-DR-C-0500
Planning IssueP02 25.06.18 KJD JSW
Drainage Strategy
MJC/KJD/171638/17-2 Reports/Drainage Strategy - Issue 01
Appendix C
Proposed green field run off rate for the development
This report was produced using the greenfield runoff tool developed by HR Wallingford and available at www.uksuds.com. The use of this tool is subject to the UK SuDS terms and conditions and licence agreement, which can both be found at http://uksuds.com/terms-and-conditions.htm. The outputs from this tool have been used to estimate storage volume requirements. The use of these results is the responsibility of the users of this tool. No liability will be accepted by HR Wallingford, the Environment Agency, CEH, Hydrosolutions or any other organisation for use of this data in the design or operational characteristics of any drainage scheme.
Greenfield runoff estimation for sites
www.uksuds.com │ Greenfield runoff tool
This is an estimation of the greenfield runoff rate limits that are needed to meet normal best practice criteria in line with Environment Agency guidance “Preliminary rainfall runoff management for developments”, W5-074/A/TR1/1 rev. E (2012) and the SuDS Manual, C753 (Ciria, 2015). This information on greenfield runoff rates may be the basis for setting consents for the drainage of surface water runoff from sites.
Site name:
Calculated by:
Latitude:
Longitude:
Reference:
Date:
Site coordinates
Site location:
Site characteristicsTotal site area (ha)
MethodologyQbar estimation methodSPR estimation method
Default Edited
SOIL typeHOST classSPR/SPRHOST
Hydrological characteristics Default Edited
SAAR (mm)Hydrological region Growth curve factor: 1 year Growth curve factor: 30 year Growth curve factor: 100 year
Notes:(1) Is QBAR < 2.0 l/s/ha?
(2) Are flow rates < 5.0 l/s?
(3) Is SPR/SPRHOST ≤ 0.3?
Greenfield runoff rates Default Edited
Qbar (l/s)1 in 1 year (l/s)1 in 30 years (l/s)1 in 100 years (l/s)
Methodology IH124
0.47
0.39
2
1.2
0.83 0.83
Lower consent flow rates may be set in which case blockage
4
0.1
2018-06-18T16:51:16
The Woodlands, Nuneaton
--- 5.0l/s if blockage from vegetation and other materials is possible.
1.5219° W
0.39
Michael Drayton
0.47
Kerry Dent
2.57
0.47
Calculate from SOIL type
52.54254° N
678678
44
1.2
2.57
Calculate from SPR and SAAR
4
---
0.93 0.93
2
6381924
work must be addressed by using appropriate drainage elements.
0.47
Where flow rates are less than 5.0 l/s consents are usually set at
Drainage Strategy
MJC/KJD/171638/17-2 Reports/Drainage Strategy - Issue 01
Appendix D
Proposed phase two surface water drainage drawings
WAR007-PE-XX-ZZ-DR-C-0502_Proposed Drainage Layout - Phase Two_171638
Michael Drayton
Junior School
100035
00
2000
3000
SWMH02
CL= TBC
IL= 140.492m AOD
SWMH03
CL= TBC
IL= 140.372m AOD
Proposed SW Drainage to connect into the
existing drainage which flows the the public
sewer.
CL= 140.880
IL = 139.230
300mm dia pipe used for
attenuation
Year 4 class room extenstion
Existing School building
SWMH04
CL=TBC
IL= 140.295m AOD
52mm dia Orifice Plate installed downstream
of the 300mm dia pipe to restrict the discharge
rate to:
1:1 year storm = 2l/s
1:30 Year storm = 3l/s
1:100 + 40% CC Storm = 4.7l/s
SWMH01
CL= TBC
IL= 140.618m AOD
SWMH05
CL= TBC
IL= 140.240m AOD
New manhole to divert existing drainage
around the proposed extension
SWMH06
CL= TBC
IL= 140.205m AOD
SWMH07
CL= TBC
IL= 140.149m AOD
EXSWMH01
CL= 140.870m AOD
IL= 140.260m AOD
New pipe to be laid to flow into
SWMH05
EXSWMH02
CL= 140.870m AOD
IL= 140.130m AOD
Existing surface water
pipe to be abandoned
and removed
Existing 300mm dia pipe
New foundations to bridge over pipe
Existing channel drain to be cleaned and unblocked
School drop off zone
surface water
drainage
KEY:
- Proposed foul water sewer
- Proposed foul water manhole (1200mmØ PCC)
- Proposed foul water inspection chamber (475mmØ
- Proposed foul water internal gully (with trap)
- Proposed foul water gully (trapless)
- Proposed foul water stub pipe
- Existing Foul Drainage
G
IG
st
KEY:
- Proposed surface water sewer
- Proposed surface water manhole
(1200mmØ PCC)
- Proposed surface water inspection
chamber (475mmØ PPIC)
- Proposed surface water gully
- Proposed rainwater downpipe
- Proposed channel drain
- Existing surface water pipe
- Existing surface water pipe to be
abandoned
G
rwp
P01 15.06.18 KJDRevision Date Drn Chk
CDM - RESIDUAL HAZARDS
1
2
3 etc.
Further possible control measures have been identified within the Design RiskAssessments which may help to mitigate these and other identified risksfurther during the construction / maintenance process.
S0 - Work in Progress
Client
Job No.
Suitability Status
Drawing Number
@ A1Scale
Project
Rev
NO DIMENSIONS TO BE SCALED FROM THIS DRAWING
This drawing is issued for the sole and exclusive use of the intended recipient and issubject to copyright in favour of Pick Everard. Pick Everard does not accept anyresponsibility or liability whatsoever for its use by a person other than the intendedrecipient.
Size
Drawing Title
T 0345 045 0050 www.pickeverard.co.uk
CDM - RESIDUAL HAZARDS The following are considered to be significant risksrelevant to this drawing, which could not be fully mitigated or removed throughdesign:
Project Code - Originator - Zone - Level - Type - Role - Number
171638 P02
Warwickshire County Council
Michael Drayton School
Proposed Drainage LayoutPhase Two
1:150
WAR7-PEV-XX-ZZ-DR-C-0502
Planning IssueP02 25.06.18 KJD JGWDraft Issue
Drainage Strategy
MJC/KJD/171638/17-2 Reports/Drainage Strategy - Issue 01
Appendix E
Surface water Miro Drainage Windes Calculations
Pick Everard Page 1
Halford House Michael Drayton SchoolCharles Street Phase 2Leicester LE1 1HA Surface Water SimulationDate 21/06/2018 Designed by KJDFile S001KJD-17-1-171638 -S...
Checked by JSWXP Solutions Network 2017.1.2
Existing Network Details for Storm
©1982-2017 XP Solutions
PN Length(m)
Fall(m)
Slope(1:X)
I.Area(ha)
T.E.(mins)
BaseFlow (l/s)
k(mm)
HYDSECT
DIA(mm)
Section Type
1.000 17.950 0.126 142.5 0.009 4.00 0.0 0.006 o 150 Pipe/Conduit1.001 20.850 0.120 173.8 0.009 4.00 0.0 0.006 o 150 Pipe/Conduit1.002 17.250 0.077 224.0 0.009 4.00 0.0 0.006 o 300 Pipe/Conduit1.003 16.521 0.015 1101.4 0.000 4.00 0.0 0.006 o 100 Pipe/Conduit
Network Results Table
PN US/IL(m)
Σ I.Area(ha)
Σ BaseFlow (l/s)
Vel(m/s)
Cap(l/s)
1.000 140.618 0.009 0.0 1.12 19.81.001 140.492 0.018 0.0 1.00 17.71.002 140.372 0.027 0.0 1.38 97.31.003 140.295 0.027 0.0 0.27 2.1
Pick Everard Page 2
Halford House Michael Drayton SchoolCharles Street Phase 2Leicester LE1 1HA Surface Water SimulationDate 21/06/2018 Designed by KJDFile S001KJD-17-1-171638 -S...
Checked by JSWXP Solutions Network 2017.1.2
Area Summary for Storm
©1982-2017 XP Solutions
PipeNumber
PIMPType
PIMPName
PIMP(%)
GrossArea (ha)
Imp.Area (ha)
Pipe Total(ha)
1.000 - - 100 0.009 0.009 0.0091.001 - - 100 0.009 0.009 0.0091.002 - - 100 0.009 0.009 0.0091.003 - - 100 0.000 0.000 0.000
Total Total Total0.027 0.027 0.027
Free Flowing Outfall Details for Storm
OutfallPipe Number
OutfallName
C. Level(m)
I. Level(m)
MinI. Level
(m)
D,L(mm)
W(mm)
1.003 EXSITING 141.130 140.280 140.280 100 0
Simulation Criteria for Storm
Volumetric Runoff Coeff 0.750 Additional Flow - % of Total Flow 0.000Areal Reduction Factor 1.000 MADD Factor * 10m³/ha Storage 2.000
Hot Start (mins) 0 Inlet Coeffiecient 0.800Hot Start Level (mm) 0 Flow per Person per Day (l/per/day) 0.000
Manhole Headloss Coeff (Global) 0.500 Run Time (mins) 60Foul Sewage per hectare (l/s) 0.000 Output Interval (mins) 1
Number of Input Hydrographs 0 Number of Storage Structures 0Number of Online Controls 1 Number of Time/Area Diagrams 0Number of Offline Controls 0 Number of Real Time Controls 0
Synthetic Rainfall Details
Rainfall Model FSR Profile Type SummerReturn Period (years) 100 Cv (Summer) 0.750
Region England and Wales Cv (Winter) 0.840M5-60 (mm) 20.000 Storm Duration (mins) 30
Ratio R 0.400
Pick Everard Page 3
Halford House Michael Drayton SchoolCharles Street Phase 2Leicester LE1 1HA Surface Water SimulationDate 21/06/2018 Designed by KJDFile S001KJD-17-1-171638 -S...
Checked by JSWXP Solutions Network 2017.1.2
Online Controls for Storm
©1982-2017 XP Solutions
Orifice Manhole: SWMH04, DS/PN: 1.003, Volume (m³): 2.1
Diameter (m) 0.052 Discharge Coefficient 0.600 Invert Level (m) 140.295
Pick Everard Page 4
Halford House Michael Drayton SchoolCharles Street Phase 2Leicester LE1 1HA Surface Water SimulationDate 21/06/2018 Designed by KJDFile S001KJD-17-1-171638 -S...
Checked by JSWXP Solutions Network 2017.1.2
Summary of Critical Results by Maximum Outflow (Rank 1) for Storm
©1982-2017 XP Solutions
Simulation CriteriaAreal Reduction Factor 1.000 Additional Flow - % of Total Flow 0.000
Hot Start (mins) 0 MADD Factor * 10m³/ha Storage 2.000Hot Start Level (mm) 0 Inlet Coeffiecient 0.800
Manhole Headloss Coeff (Global) 0.500 Flow per Person per Day (l/per/day) 0.000Foul Sewage per hectare (l/s) 0.000
Number of Input Hydrographs 0 Number of Storage Structures 0Number of Online Controls 1 Number of Time/Area Diagrams 0Number of Offline Controls 0 Number of Real Time Controls 0
Synthetic Rainfall DetailsRainfall Model FSR Ratio R 0.400
Region England and Wales Cv (Summer) 0.750M5-60 (mm) 20.000 Cv (Winter) 0.840
Margin for Flood Risk Warning (mm) 300.0Analysis Timestep 2.5 Second Increment (Extended)
DTS Status ONDVD Status ON
Inertia Status ON
Profile(s) Summer and WinterDuration(s) (mins) 15, 30, 60, 120, 180, 240, 360, 480, 600,
720, 960, 1440Return Period(s) (years) 1, 2, 30, 100
Climate Change (%) 0, 0, 0, 40
PNUS/MHName Storm
ReturnPeriod
ClimateChange
First (X)Surcharge
First (Y)Flood
First (Z)Overflow
OverflowAct.
Water Level(m)
1.000 SWMH01 15 Summer 100 +40% 100/15 Summer 141.1281.001 SWMH02 15 Summer 100 +40% 30/15 Winter 141.1231.002 SWMH03 15 Summer 100 +40% 30/15 Winter 141.1221.003 SWMH04 30 Winter 100 +40% 1/15 Summer 141.113
PNUS/MHName
SurchargedDepth(m)
FloodedVolume(m³)
Flow /Cap.
Overflow(l/s)
PipeFlow(l/s) Status
LevelExceeded
1.000 SWMH01 0.360 0.000 0.32 5.6 FLOOD RISK1.001 SWMH02 0.481 0.000 0.57 9.1 FLOOD RISK1.002 SWMH03 0.450 0.000 0.15 10.1 FLOOD RISK1.003 SWMH04 0.718 0.000 2.06 4.7 FLOOD RISK
Pick Everard Page 5
Halford House Michael Drayton SchoolCharles Street Phase 2Leicester LE1 1HA Surface Water SimulationDate 21/06/2018 Designed by KJDFile S001KJD-17-1-171638 -S...
Checked by JSWXP Solutions Network 2017.1.2
Rainfall Hyetograph for 15 minute 100 year Summer I+40%for Pipe 1.000 (Storm)
©1982-2017 XP Solutions
Time(mins)
Rain(mm/hr)
Time(mins)
Rain(mm/hr)
Time(mins)
Rain(mm/hr)
Time(mins)
Rain(mm/hr)
Time(mins)
Rain(mm/hr)
1 46.489 4 69.905 7 314.575 10 158.945 13 58.2322 51.117 5 92.770 8 488.233 11 92.770 14 51.1173 58.232 6 158.945 9 314.575 12 69.905 15 46.488
Pick Everard Page 6
Halford House Michael Drayton SchoolCharles Street Phase 2Leicester LE1 1HA Surface Water SimulationDate 21/06/2018 Designed by KJDFile S001KJD-17-1-171638 -S...
Checked by JSWXP Solutions Network 2017.1.2
Rainfall Hyetograph for 15 minute 100 year Summer I+40%for Pipe 1.001 (Storm)
©1982-2017 XP Solutions
Time(mins)
Rain(mm/hr)
Time(mins)
Rain(mm/hr)
Time(mins)
Rain(mm/hr)
Time(mins)
Rain(mm/hr)
Time(mins)
Rain(mm/hr)
1 46.489 4 69.905 7 314.575 10 158.945 13 58.2322 51.117 5 92.770 8 488.233 11 92.770 14 51.1173 58.232 6 158.945 9 314.575 12 69.905 15 46.488
Pick Everard Page 7
Halford House Michael Drayton SchoolCharles Street Phase 2Leicester LE1 1HA Surface Water SimulationDate 21/06/2018 Designed by KJDFile S001KJD-17-1-171638 -S...
Checked by JSWXP Solutions Network 2017.1.2
Rainfall Hyetograph for 15 minute 100 year Summer I+40%for Pipe 1.002 (Storm)
©1982-2017 XP Solutions
Time(mins)
Rain(mm/hr)
Time(mins)
Rain(mm/hr)
Time(mins)
Rain(mm/hr)
Time(mins)
Rain(mm/hr)
Time(mins)
Rain(mm/hr)
1 46.489 4 69.905 7 314.575 10 158.945 13 58.2322 51.117 5 92.770 8 488.233 11 92.770 14 51.1173 58.232 6 158.945 9 314.575 12 69.905 15 46.488
Pick Everard Page 8
Halford House Michael Drayton SchoolCharles Street Phase 2Leicester LE1 1HA Surface Water SimulationDate 21/06/2018 Designed by KJDFile S001KJD-17-1-171638 -S...
Checked by JSWXP Solutions Network 2017.1.2
Rainfall Hyetograph for 30 minute 100 year Winter I+40%for Pipe 1.003 (Storm)
©1982-2017 XP Solutions
Time(mins)
Rain(mm/hr)
Time(mins)
Rain(mm/hr)
Time(mins)
Rain(mm/hr)
Time(mins)
Rain(mm/hr)
Time(mins)
Rain(mm/hr)
Time(mins)
Rain(mm/hr)
1 12.494 6 41.702 11 121.527 16 224.946 21 95.228 26 40.3832 30.695 7 46.856 12 150.599 17 206.590 22 72.965 27 40.3673 38.446 8 57.054 13 180.722 18 180.722 23 57.054 28 38.4464 40.367 9 72.965 14 206.590 19 150.599 24 46.856 29 30.6955 40.383 10 95.228 15 224.946 20 121.527 25 41.702 30 12.493