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Lidl, Chippenham Flood Risk Assessment & Drainage Strategy

w10375-170918-FRA & Drainage Strategy

Appendix C –Infiltration Tests

3083

0

Stratum boundaries

KEY TO EXPLORATORY HOLE LOGS

General Comments

The process of drilling and sampling will inevitably lead to disturbance, mixing or loss of material in some soil and rocks.

Indicated water levels are those recorded during the process of drilling or excavating exploratory holes and may not represent standing water levels.

Legends are drawn in accordance with BS 5930:1999 incorporating Amendment 2.

All depths are measured along the axis of the borehole and are related to ground level at the point of entry.

Revision date: 01/07/13

(*250 - Where full test drive not completed, linearly extrapolated 'N' value reported, ** - Denotes no effective penetration)

Logging

The logging of soils and rocks has been carried out in general accordance with BS 5930:1999 incorporating Amendments 1 (2006) & 2 (2010).Amendment 1 removes text superceded by BS ENO ISO 14688-1:2002, BS EN ISO 14688-2:2004 and BS EN ISO 14689-1:2003, and makesreference to the relevant standard for each affected sub clause. Amendment 2 removes text superceded by BS EN ISO 22475-1:2006 and makesreference to the relevant standard for each affected sub clause.

Chalk is logged in general accordance with Lord et al (2002) CIRIA C574. Where possible, dynamic samples in chalk have been logged inaccordance with CIRIA C574; descriptions and gradings should be treated with caution given the potential for sample disturbance.

For rocks the term fracture has been used to identify a mechanical break within the core. Where possible incipient and drilling induced fractures havebeen excluded from the assessment of fracture state. Where doubt exists, a note has been made in the descriptions. All fractures are considered tobe continuous unless otherwise reported.

Made Ground is readily identifiable when, within the material make up, man made constituents are evident. Where Made Ground appears to bereworked natural material the differentiation between in situ natural deposits and Made Ground is much more difficult to ascertain. The interpretationof Made Ground within the logs should therefore be treated with caution.

The descriptors "topsoil" and "tarmacadam" are used as generic terms and do not imply conformation to any particular standard or composition.

Soil

Backfill

ConcreteGranular

response zone

Estimated boundary Grading boundary

Geotechnical Engineering Limited

D* Contamination

C Core

B Bulk disturbed

U Undisturbed

LB Large bulk disturbed

UT Undisturbed thin wall

W Water

P Piston

D Small disturbed

X Dynamic

Test type

Cs Core subsample (prepared)

S SPT - Split spoon sampler followed by uncorrected SPT 'N' Value

C SPT - Solid cone followed by uncorrected SPT 'N' Value

Sample/core range/If

Dynamic sample

Undisturbed sample - open drive including thin wall. Symbol length reflects recovery

x x = Total Core Recovery (TCR) as percentage of core run

y y = Solid Core Recovery (SCR) as percentage of core run. Assessment of core is based on full diameter.

z z = Rock Quality Designation (RQD). The amount of solid core greater than 100mm expressed as percentage of core run.

Instrumentation

Where SPT has been carried out at beginning of core run, disturbed section of core excluded from SCR and RQD assessment.

If - fracture spacing - the average fracture spacing (mm) over the indicated length of core. Where spacing varies signficantly, the minimum,

average and maximum values are given. NI = non-intact core NA = not applicable

H Hand vane - direct reading in kPa - not corrected for BS1377 (1990). Re* denotes refusal

M Mackintosh probe - number of blows to achieve 100mm penetration

PP Pocket penetrometer - direct reading in kg/sq.cm

Vo Headspace vapour reading, uncorrected peak values in ppm, using a PID (calibrated with Isobutylene, using a 10.6eV bulb)

Sample type

Porous

tip

Perforated

standpipe

Doc. No. A01 Rev No. 14DC: JH

Bentonite

seal

Cement/

bentonite

grout

0.20

0.50

0.80

2.00

1

2

3

4

5

6

7

8

9

10

B

D

B

D

B

D

B

D

B

D

0.00

0.00

0.30

0.30

0.60

0.60

0.90

0.90

1.60

1.60

- 0.20

- 0.20

- 0.40

- 0.40

- 0.70

- 0.70

- 1.10

- 1.10

- 1.80

- 1.801.70m:Seepage

1.92m

Grass over soft dark brown slightly gravelly clayey SILT with rare potteryfragments (up to 30mm) and frequent roots and rootlets (up to 2mm diam). Gravelis subangular fine to coarse brick and limestone. (MADE GROUND)

Soft light brown locally light orangish brown slightly gravelly silty CLAY withfrequent rootlets (up to 1mm diam) Gravel is subangular fine to coarse limestone.

Soft light yellowish brown and light orangish brown gravelly silty CLAY with rarerootlets (up to 1mm diam). Gravel is angular to subangular fine to coarse chertand limestone.

Light brownish yellow and light grey LIMESTONE recovered as slightly sandyslightly clayey angular to subrounded fine to coarse gravel with a high angularcobble content.

1.50 - 2.00m: Low angular limestone cobble content.

Trial pit completed at 2.00m.

Geo

tech

nica

l Eng

inee

ring

Ltd,

Tel

. 014

52 5

2774

3

30

830,

MID

DLE

FIE

LD C

HIP

PE

NH

AM

.GP

J T

RIA

LJH

.GP

J G

EO

TE

CH

.GLB

02

/07/

2015

15:

07:0

6 R

D

GR

End Date

MIDDLEFIELDS ALC, HUNGERDOWN LANE, CHIPPENHAM

depth level

(m)legend

CONTRACT CHECKED

Notes

TRIAL PIT LOG

(m)

Start Date

water

record

sample/test

TP01SITE

CRADDYS

2.00 m

30830EXPLORATORY HOLE LOGS SHOULD BE READ IN CONJUNCTION WITH KEY SHEETS

Sketch of Foundation - Not to scale. All dimensions in metres.

no/type

Trial pit excavated by JCB 3CX mechanical excavator.Groundwater seepage encountered at 1.70m.Trial pit sides remained stable and vertical.Trial pit dimensions 1.70x0.70x2.00m.Trial pit terminated on encountering groundwater.On completion, the trial pit was backfilled with materials arising.

8 June 2015

8 June 2015

CLIENT


depth (m)description

Sheet 1 of 1

Scale 1 : 25

result

Depth

CT

0.30

0.70

1.501.50m:Seepage

Grass over soft dark brown slightly gravelly clayey SILT with rare potteryfragments (up to 30mm) and frequent roots and rootlets (up to 2mm diam). Gravelis subangular fine to coarse brick and limestone. (MADE GROUND)

Soft light brown locally light orangish brown slightly gravelly silty CLAY withfrequent rootlets (up to 1mm diam) Gravel is subangular fine to coarse limestone.

Light brownish yellow and light grey LIMESTONE recovered as slightly sandyslightly clayey angular to subrounded fine to coarse gravel with a high angularcobble content.


Geo

tech

nica

l Eng

inee

ring

Ltd,

Tel

. 014

52 5

2774

3

30

830,

MID

DLE

FIE

LD C

HIP

PE

NH

AM

.GP

J T

RIA

LJH

.GP

J G

EO

TE

CH

.GLB

02

/07/

2015

15:

07:0

7 R

D

GR

End Date


depth level

(m)legend

CONTRACT CHECKED

Notes

TRIAL PIT LOG

(m)

Start Date

water

record

sample/test

TP01ASITE

CRADDYS

1.50 m



no/type

Trial pit excavated by JCB 3CX mechanical excavator.Groundwater seepage encountered at 1.50m.Trial pit sides remained stable and vertical.Trial pit dimensions 1.80x0.70x1.50m.Trial pit terminated on encountering groundwater.On completion, the trial pit was backfilled with materials arising.

8 June 2015

8 June 2015

CLIENT



Sheet 1 of 1

Scale 1 : 25

result

Depth

CT

0.30

0.90

1.80

2.00

1

2

3

4

5

6

7

8

B

D

B

D

B

D

B

D

0.10

0.10

0.40

0.40

1.00

1.00

1.90

1.90

- 0.20

- 0.20

- 0.60

- 0.60

- 1.20

- 1.20

- 2.00

- 2.00Dry

Grass over soft brown slightly gravelly clayey SILT with frequent roots and rootlets(up to 2mm diam). Gravel is subangular and subrounded fine to coarse brick andlimestone. (MADE GROUND)

Yellowish brown and orangish brown locally light grey LIMESTONE recovered asslightly sandy slightly clayey angular and subangular fine to coarse gravel with ahigh angular cobble content.

Light yellowish brown locally light orangish brown LIMESTONE recovered asslightly sandy clayey angular to subrounded fine to coarse gravel with a mediumangular cobble content and frequent shell fragments (up to 2mm).

1.50 - 1.80m: Slightly clayey.

Grey and light yellowish brown LIMESTONE recovered as slightly sandy clayeyangular to subrounded fine to coarse fossiliferous gravel with a medium angularcobble content.


Geo

tech

nica

l Eng

inee

ring

Ltd,

Tel

. 014

52 5

2774

3

30

830,

MID

DLE

FIE

LD C

HIP

PE

NH

AM

.GP

J T

RIA

LJH

.GP

J G

EO

TE

CH

.GLB

02

/07/

2015

15:

07:0

7 R

D

GR

End Date


depth level

(m)legend

CONTRACT CHECKED

Notes

TRIAL PIT LOG

(m)

Start Date

water

record

sample/test

TP02SITE

CRADDYS

2.00 m



no/type

Trial pit excavated by JCB 3CX mechanical excavator.Groundwater not encountered.Trial pit sides remained stable and vertical.Trial pit dimensions 2.10x0.70x2.00m.Soakaway test undertaken in trial pit 1.23m-2.00m.On completion, the trial pit was backfilled with materials arising.

8 June 2015

8 June 2015

CLIENT



Sheet 1 of 1

Scale 1 : 25

result

Depth

CT

0.30

0.70

1.30

1.90

1

2

3

4

5

6

7

8

B

D

B

D

B

D

B

D

0.10

0.10

0.40

0.40

0.80

0.80

1.40

1.40

- 0.20

- 0.20

- 0.60

- 0.60

- 1.00

- 1.00

- 1.60

- 1.60

1.70m:Seepage.

1.80m

Grass over soft brown slightly gravelly clayey SILT with frequent roots and rootlets(up to 2mm diam). Gravel is subangular and subrounded fine to coarse brick,concrete and limestone. (MADE GROUND)

Soft light brown slightly gravelly silty CLAY with frequent rootlets (up to 1mmdiam) and a medium angular limestone cobble content. Gravel is angular andsubangular fine to coarse limestone.

Light brown locally light orangish brown slightly clayey angular to subrounded fineto coarse limestone GRAVEL.0.85 - 0.90m: Band of soft orangish brown clay.

Light brown locally light grey LIMESTONE recovered as clayey angular tosubrounded fine to coarse gravel with a high angular cobble content.


Geo

tech

nica

l Eng

inee

ring

Ltd,

Tel

. 014

52 5

2774

3

30

830,

MID

DLE

FIE

LD C

HIP

PE

NH

AM

.GP

J T

RIA

LJH

.GP

J G

EO

TE

CH

.GLB

02

/07/

2015

15:

07:0

8 R

D

GR

End Date


depth level

(m)legend

CONTRACT CHECKED

Notes

TRIAL PIT LOG

(m)

Start Date

water

record

sample/test

TP03SITE

CRADDYS

1.90 m



no/type

Trial pit excavated by JCB 3CX mechanical excavator.Groundwater seepage encountered at 1.70mTrial pit sides remained stable and vertical.Trial pit dimensions 1.80x0.70x1.90m.Trial pit terminated on encountering groundwater.On completion, the trial pit was backfilled with materials arising.

8 June 2015

8 June 2015

CLIENT



Sheet 1 of 1

Scale 1 : 25

result

Depth

CT


SOAKAWAY TESTCLIENT CRADDYS

SITE MIDDLEFIELDS ALC, HUNGERDOWN LANE, CHIPPENHAM TRIAL PIT TP02DATE 08/06/15

TEST 1LENGTH 2.00 m

BREADTH 0.70 m

DEPTH 2.00 m

WATER LEVEL Dry

FILL LEVEL 1.23 m

vp75-25 m3

ap50 m2

tp75-25 min

TEST 2LENGTH m

BREADTH m

DEPTH m

WATER LEVEL m

FILL LEVEL m

vp75-25 m3

ap50 m2

tp75-25 min

soil infiltration rate, f * x 10-* ms-1

TEST 3LENGTH m

BREADTH m

DEPTH m

WATER LEVEL m

FILL LEVEL m

vp75-25 m3

ap50 m2

tp75-25 min

soil infiltration rate, f * x 10-* ms-1

Remarks CONTRACT CHECKED

RD 30830 CT

Test carried out in accordance with BRE 365 (2007). Insufficient fall

in water level to calculate infiltration rate.

Too little water take to calculate infiltration rate.

1.00

1.20

1.40

1.60

1.80

2.00

0 50 100 150 200 250

Dep

th to

wat

er (m

)

Time (minutes)

1.00

1.20

1.40

1.60

1.80

2.00

0 50 100 150 200 250

Dep

th to

wat

er (m

)

Time (minutes)

1.00

1.20

1.40

1.60

1.80

2.00

0 50 100 150 200 250

Dep

th to

wat

er (m

)

Time (minutes)

25% full

75% full

rev07 08/06/09 JH



Appendix D –Sewer Plan and Correspondence

Reproduced from the Ordnance Survey map by permission on behalf of the Controller of Her Majesty's Stationery Office © Crown Copyright . Licence 100019539.

Centre:

N

EW

S

Printed on:

Information in this plan is provided for identification

purposes only. No warranty as to accuracy is given or

implied. The precise route of pipe work may not exactly

match that shown. Wessex Water does not accept liability

for inaccuracies.

Sewers and lateral drains adopted by Wessex Water under

the Water Industry (Schemes for Adoption of Private

Sewers) Regulations 2011 are to be plotted over time and

may not yet be shown.

In carrying out any works, you accept liability for the cost

of any repairs to Wessex Water apparatus damaged as a

result of your works. You are advised to commence

excavations using hand tools only. Mechanical digging

equipment should not be used until pipe work has been

precisely located.

If you are considering any form of building works and pipe

work is shown within the boundary of your property or a

property to be purchased (or very close by) a surveyor

should plot its exact position prior to commencing works or

purchase. Building over or near Wessex Water’s apparatus

is not normally permitted.

WATER MAINS Public Private

Public

Raw Water

Abandoned

Valve Hydrant PRV Meter

SEWERS Public - Section 104 - Private

Foul

Combined

Surface

Abandoned sewers

OTHER WESSEX PIPES

Rising Mains

Effluent Disposal Main

Overflow

NON-WESSEX PIPES

Private Rising Mains

Culverted Water Course

Highway Drain

Redland House

25/05/2017 16:37

390529.28 , 174150.01

1

Ifan Jones

From: Teddy Takyi-Amuah <[email protected]>Sent: 05 June 2017 10:47To: Ifan JonesCc: Planning LiaisonSubject: WW RESP : ST97SW_400 Lidl, Chippenham-Pre Deevloepr EnquriyAttachments: Guidance notes for building over or near a sewer.pdf; Guidance notes for a sewer

diversion.pdf

Categories: Information received

Good Morning Ifan, Apologies for the delay, our response to this site as follows: According to our records there, are existing public foul, surface water and water mains passing through the western and northern boundaries of the site including the following?

• 225 mm clay public foul sewer • 375 mm concrete public surface water sewer • 8” PVC water main (nb marked as “assumed route”) • 3” Cl water main

The Onus will be with the developer to locate the afore-mentioned Wessexwater assets on site and marked on deposited drawings. There must be no building within 3 metres of these pipes (5 metres for the 8” water main) or tree planting within 6 metres. Subject to application, engineering agreement and at the developers cost it may be possible to divert these apparatus to achieve easement within preferred layout as appropriate. Proposed Surface Water comments: Surface water to be discharged to local land drainage systems with agreed flood risk measures approved by the Lead Local Flood Authority. Surface water connections to the public foul sewer system will not be permitted, as surface water discharges to the public sewer will lead to sewer flooding.

- A more suitable approach would be to discuss any run off rates & any necessary Flood risk measures with the Lead Local Flood authority. Once these rates have been agreed, we will then be able to determine surface water capacity for the proposed flow rates. This should be based on the size of the site, impervious area etc.

If surface water discharge is required to the existing public surface water sewer, the applicant will need to prove no increase in existing positively connected flows (30 % betterment for climate change). The LLFA may also have further requirements under flood risk measures and SuDs hierarchy.

2

1. Existing site possibly drained to our existing 375 mm SWS; therefore, we would want to see that the new surface water discharge rates over all critical return events no greater than the existing runoff based on the existing hardstanding area. I.e. - the developer calculates existing discharge rate for the 1, 2, 5, 10, 30 and 100yr +30 % CC in accordance with any planning stipulations and NPPF framework and matches these rates on the same events on the proposed SW flows and provided the required volume of storage behind the control. I.e. – no increase on SW flows over the existing rates discharging into our sewer.

2. Obvious point of connection is to our existing 375 mm diameter SWS that runs through the North of site. Developer will probably need to go over our existing FWS with it being deeper than the SW with no determent if they were to connect at this location in accordance with the above.

3. A sterilisation zone will be implemented and adhered to of 3.0 meters from our existing sewers to the North with no new dwellings closer than this.

As previously advised, the site will have had connections to our networks, which can be re-used as appropriate or sealed at the point of connection with agreement required from Wessex Water.

4

From: Ifan Jones [mailto:[email protected]] Sent: 15 May 2017 15:11 To: Planning Liaison <[email protected]> Subject: w10375-Lidl, Chippenham-Pre Deevloepr Enquriy Proposed Lidl Store at the former Middlefield Adult Training Centre, Chippenham, SN14 0JP. Grid reference: 390550E 174122N. Dear Sir / Madam, We are currently preparing a Flood Risk Assessment & Drainage Strategy for a site at the above address. I attach a location plan for reference. The site currently comprises the former Middlefield Adult Training Facility Centre. The development proposal is for the construction of a new Lidl food store with associated landscaping, parking and access arrangements. I attach a development plan for reference. Where infiltration is not feasible, we currently propose to discharge surface water into the adjacent Wessex Water sewerage network. Please could you advise if there will be any specific requirements for a Surface Water Drainage Strategy at this site i.e. specify any discharge rate requirements for the site. If you have any questions or require any further information to process my request please don’t hesitate to contact us. Kind regards, Ifan Jones Bsc (Hons) MSc Environmental Consultant 01824 702220

Ruthin - Chester - Manchester - Hyderabad Assessment, Modelling, Design

For email confidentiality, limitations and company details please see our disclaimer webpage. Registered in Wales under company no. 3577754. Waterco Ltd, Eden Court, Ruthin LL15 1NJ

______________________________________________________________________

5

This email is confidential. If you are not the intended recipient, you must not copy, distribute, disclose or use the information contained in it. If you have received this communication in error, please tell us immediately by return email and then delete the email and any copies of it from your computer system. Thank you.

Wessex Water Services Limited, Registered in England No 2366648. Registered Office – Wessex Water Operations Centre, Claverton Down Road, Claverton Down, Bath, BA2 7WW

______________________________________________________________________

1

Ifan Jones

From: Drainage <[email protected]>Sent: 09 June 2017 11:48To: Ifan JonesCc: Developmentmanagement; Dave OgborneSubject: FW: w10375-Lidl,Chippenham-Surface Water Drainage Attachments: P1094 Concept Site Layout Plan.pdf; surface water flood risk 1 in 30/100

Categories: Information received

Ifan Thank you for your email below, the information you seek is normally dealt with via a preapp through our planning department, however I supply some of the requested information:

• Infiltration is unlikely to work – area is served by public storm sewer • We would expect to see details of existing disposal methods and flow rates • As government guidelines brownfield sites should aspire to greenfield run off rates where ever possible • Likely that WW would seek you proving existing connections and require no increase in flow rate • Council will look at 20% reduction in flow rate if greenfield cannot be achieved • 40% climate change to be used • Any submission will need to detail attenuation, ownership and maintenance regime • Mapping shows site lies in an area affected by surface water flood risk for 1 in 30/100 event (attached) – this

will need to be addressed in application Hope this helps Peter Weston, Land Drainage Engineer, Wiltshire Council From: Ifan Jones [mailto:[email protected]] Sent: 15 May 2017 14:49 To: Drainage Subject: w10375-Lidl,Chippenham-Surface Water Drainage Proposed Lidl Store at the former Middlefield Adult Training Centre, Chippenham, SN14 0JP. Grid reference: 390550E 174122N. Dear Sir / Madam, We are currently preparing a Flood Risk Assessment & Drainage Strategy for a site at the above address. I attach a location plan for reference. The site currently comprises the former Middlefield Adult Training Facility Centre. The development proposal is for the construction of a new Lidl food store with associated landscaping, parking and access arrangements. I attach a development plan for reference. Where infiltration is not feasible, we currently propose to discharge surface water into the adjacent Wessex Water sewerage network. We have submitted a developer enquiry to Wessex Water to establish if this is feasible. Please could you advise if there will be any specific requirements for a Surface Water Drainage Strategy at this site i.e. specify any flow rate requirements and attenuation storage requirements (i.e. should 20%, 30% or 40% climate change be applied when sizing attenuation features). Please can you also advise if you have any requirements for the use of SuDS. Please could you also advise if you have any records of historical flooding in this area?

2

If you have any questions or require any further information to process my request please don’t hesitate to contact us. Kind regards, Ifan Jones Bsc (Hons) MSc Environmental Consultant 01824 702220

Ruthin - Chester - Manchester - Hyderabad Assessment, Modelling, Design

For email confidentiality, limitations and company details please see our disclaimer webpage. Registered in Wales under company no. 3577754. Waterco Ltd, Eden Court, Ruthin LL15 1NJ

--------------------------------------------------------------------

This email originates from Wiltshire Council and any files transmitted with it may contain confidential information and may be subject to Copyright or Intellectual Property rights. It is intended solely for the use of the individual or entity to whom they are addressed. If you have received this email in error please notify the sender and delete the email from your inbox. Any disclosure, reproduction, dissemination, modification and distribution of the contents of the email is strictly prohibited. Email content may be monitored by Wiltshire Council to ensure compliance with its policies and procedures. No contract is intended by this email, and any personal opinions expressed in this message are those of the sender and should not be taken as representing views of Wiltshire Council. Please note Wiltshire Council utilises anti-virus scanning software but does not warrant that any e-mail or attachments are free from viruses or other defects and accepts no liability for any losses resulting from infected e-mail transmissions. Receipt of this e-mail does not imply consent to use or provide this e-mail address to any third party for any purpose. Wiltshire Council will not request the disclosure of personal financial information by means of e-mail any such request should be confirmed in writing by contacting Wiltshire Council.



Appendix E – Environment Agency Flood Maps

DATE:

16/05/2017

PLOT NAME:

w10375-EA_FloodZone

REV:

-

DRAWN:

IJ

CHECKED:

JR

APPROVED:

VG

PLOT SCALE @ A3:

(UNLESS STATED OTHERWISE)1:5,000

PLOT STATUS:

FINAL

PLOT TITLE:

SCHEME:

LIDL, CHIPPENHAM

CLIENT:

LIDL UK GMBH

LEGEND

Site Boundary

EA Main Rivers

EA Flood Zone 2

EA Flood Zone 3

0 100 200 300 400 50050m

NOTES:1) ALL DIMENSIONS ARE IN METRES AND ALL LEVELS IN METRESABOVE ORDNANCE DATUM UNLESS STATED OTHERWISE±

CONTAINS OS DATA © CROWN COPYRIGHT (2017)© ENVIRONMENT AGENCY COPYRIGHT AND/OR DATABASE RIGHT 2017. ALL RIGHTS RESERVED. SOME FEATURES OF THIS MAP ARE BASED ON DIGITAL SPATIAL DATA FROM THE CENTRE FOR ECOLOGY AND HYDROLOGY, © NERC (CEH). © CROWN COPYRIGHT AND DATABASE RIGHTS 2004 ORDNANCE SURVEY 100024198

EA FLOOD MAP FOR PLANNINGMAY 2017

www.waterco.co.uk

DATE:

16/05/2017

PLOT NAME:

w10375-EA_HistoricFlooding

REV:

-

DRAWN:

IJ

CHECKED:

JR

APPROVED:

VG

PLOT SCALE @ A3:


PLOT STATUS:

FINAL

PLOT TITLE:

SCHEME:

LIDL, CHIPPENHAM

CLIENT:

LIDL UK GMBH

LEGEND

Site Boundary

Historic Flood Map

0 100 200 300 400 50050m


CONTAINS OS DATA © CROWN COPYRIGHT (2017)EA FLOODING FROM RESERVOIR DATA © CROWN COPYRIGHT (2017)

EA HISTORIC FLOOD MAPMAY 2017

www.waterco.co.uk

DATE:

16/05/2017

PLOT NAME:

w10375-EA_SW

REV:

-

DRAWN:

IJ

CHECKED:

JR

APPROVED:

VG

PLOT SCALE @ A3:


PLOT STATUS:

FINAL

PLOT TITLE:

SCHEME:

LIDL, CHIPPENHAM

CLIENT:

LIDL UK GMBH

LEGEND

Site Boundary

Very Low (less than 0.1%)

Low (between 0.1% and 1.0%)

Medium (between 1.0% and 3.3%)

High (3.3% or greater)

0 100 200 300 400 50050m


CONTAINS OS DATA © CROWN COPYRIGHT (2017)© ENVIRONMENT AGENCY COPYRIGHT AND/OR DATABASE RIGHT 2017. ALL RIGHTS RESERVED. SOME FEATURES OF THIS MAP ARE BASED ON DIGITAL SPATIAL DATA FROM THE CENTRE FOR ECOLOGY AND HYDROLOGY, © NERC (CEH). © CROWN COPYRIGHT AND DATABASE RIGHTS 2004 ORDNANCE SURVEY 100024198

EA FLOOD MAP FORSURFACE WATER

MAY 2017

www.waterco.co.uk

DATE:

16/05/2017

PLOT NAME:

w10375-EA_RES

REV:

-

DRAWN:

IJ

CHECKED:

JR

APPROVED:

VG

PLOT SCALE @ A3:


PLOT STATUS:

FINAL

PLOT TITLE:

SCHEME:

LIDL, CHIPPENHAM

CLIENT:

LIDL UK GMBH

LEGEND

Site Boundary

EA Reservoir Flood Map

0 100 200 300 400 50050m


CONTAINS OS DATA © CROWN COPYRIGHT (2017)EA FLOODING FROM RESERVOIR DATA © CROWN COPYRIGHT (2017)

EA FLOOD RISKFROM RESERVOIRS

MAY 2017

www.waterco.co.uk

No Data Coverage - Area at Low Risk



Appendix F – SFRA / PRFA Maps

Drawing Title

www.scottwilson.com

Legend

Scale at A3 :

Drw

Chk

App

Date Date

Rev

Drawing NumberMain Rivers

Artificial Flood Sources

Groundwater Flooding Incidents

Highways Historic FloodingFRISS IncidentsFlood Source

Fluvial

Fluvial, Main River

Fluvial, Other, Sewerage

Fluvial, Sewerage

Fluvial, Surface Water Runoff

Groundwater

Main River

Sewerage

Surface Water Runoff

District Boundaries

Figure 4a1:50,000

DH

CP

MC

24.10.07

Wiltshire Strategic Flood Risk Assessment

North Wiltshire Other Sources of Flooding

Reproduced from Ordnance Survey digital map data (c) Crown copyright 2006. All rights reserved. Licence number 100023455, 2007

Site Location

Site Location



Appendix G – Runoff Rates and MicroDrainage Storage Volumes

w10375 Author: IJ

Lidl, Chippenham Checked: JR

ReFH2 Runoff Rates Date: 16/06/2017

*Runoff Rates printed from the ReFH Flood Modelling software package

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Eden Court Lidl

Lon Parcwr Business Park Chippenham

Denbighshire LL15 1NJ Attenuation calcs 1 in 30

Date 09/06/2017 Designed by IJ

File Checked by JR

XP Solutions Source Control 2016.1

Summary of Results for 30 year Return Period

©1982-2016 XP Solutions

StormEvent

MaxLevel(m)

MaxDepth(m)

MaxControl(l/s)

MaxVolume(m³)

Status

15 min Summer 9.454 0.454 5.3 142.2 O K30 min Summer 9.546 0.546 5.4 171.0 O K60 min Summer 9.647 0.647 5.4 202.4 O K120 min Summer 9.747 0.747 5.4 233.7 Flood Risk180 min Summer 9.796 0.796 5.4 249.1 Flood Risk240 min Summer 9.822 0.822 5.4 257.4 Flood Risk360 min Summer 9.837 0.837 5.4 261.9 Flood Risk480 min Summer 9.829 0.829 5.4 259.5 Flood Risk600 min Summer 9.823 0.823 5.4 257.7 Flood Risk720 min Summer 9.817 0.817 5.4 255.8 Flood Risk960 min Summer 9.798 0.798 5.4 249.8 Flood Risk1440 min Summer 9.755 0.755 5.4 236.2 Flood Risk2160 min Summer 9.679 0.679 5.4 212.6 O K2880 min Summer 9.600 0.600 5.4 187.7 O K4320 min Summer 9.396 0.396 5.3 123.9 O K5760 min Summer 9.239 0.239 5.3 74.7 O K7200 min Summer 9.126 0.126 5.2 39.3 O K8640 min Summer 9.049 0.049 5.2 15.4 O K10080 min Summer 9.010 0.010 5.2 3.2 O K

15 min Winter 9.511 0.511 5.4 159.9 O K30 min Winter 9.615 0.615 5.4 192.6 O K

StormEvent

Rain(mm/hr)

FloodedVolume(m³)

DischargeVolume(m³)

Time-Peak(mins)

15 min Summer 81.145 0.0 147.0 1630 min Summer 49.812 0.0 180.3 3160 min Summer 30.578 0.0 221.8 62120 min Summer 18.771 0.0 272.2 122180 min Summer 14.110 0.0 306.4 180240 min Summer 11.523 0.0 334.1 240360 min Summer 8.662 0.0 377.0 360480 min Summer 7.074 0.0 410.5 420600 min Summer 6.045 0.0 438.5 486720 min Summer 5.317 0.0 462.7 554960 min Summer 4.322 0.0 501.1 6821440 min Summer 3.228 0.0 561.5 9642160 min Summer 2.411 0.0 629.6 13682880 min Summer 1.960 0.0 682.1 17644320 min Summer 1.400 0.0 730.6 25125760 min Summer 1.102 0.0 768.0 32327200 min Summer 0.916 0.0 797.5 38968640 min Summer 0.787 0.0 821.9 450410080 min Summer 0.693 0.0 843.9 5144

15 min Winter 81.145 0.0 164.6 1630 min Winter 49.812 0.0 202.3 31

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StormEvent

MaxLevel(m)

MaxDepth(m)

MaxControl(l/s)

MaxVolume(m³)

Status

60 min Winter 9.731 0.731 5.4 228.8 Flood Risk120 min Winter 9.853 0.853 5.5 267.0 Flood Risk180 min Winter 9.918 0.918 5.5 287.3 Flood Risk240 min Winter 9.956 0.956 5.5 299.3 Flood Risk360 min Winter 9.992 0.992 5.5 310.4 Flood Risk480 min Winter 9.997 0.997 5.5 312.1 Flood Risk600 min Winter 9.986 0.986 5.5 308.6 Flood Risk720 min Winter 9.968 0.968 5.5 303.0 Flood Risk960 min Winter 9.940 0.940 5.5 294.1 Flood Risk1440 min Winter 9.869 0.869 5.5 272.0 Flood Risk2160 min Winter 9.743 0.743 5.4 232.5 Flood Risk2880 min Winter 9.613 0.613 5.4 191.9 O K4320 min Winter 9.315 0.315 5.3 98.5 O K5760 min Winter 9.104 0.104 5.2 32.6 O K7200 min Winter 9.001 0.001 5.2 0.2 O K8640 min Winter 9.000 0.000 4.5 0.0 O K10080 min Winter 9.000 0.000 4.0 0.0 O K

StormEvent

Rain(mm/hr)

FloodedVolume(m³)


Time-Peak(mins)

60 min Winter 30.578 0.0 247.8 60120 min Winter 18.771 0.0 304.7 120180 min Winter 14.110 0.0 344.0 178240 min Winter 11.523 0.0 374.1 234360 min Winter 8.662 0.0 421.7 348480 min Winter 7.074 0.0 459.6 456600 min Winter 6.045 0.0 491.1 560720 min Winter 5.317 0.0 518.1 590960 min Winter 4.322 0.0 561.8 7381440 min Winter 3.228 0.0 629.1 10502160 min Winter 2.411 0.0 704.4 14922880 min Winter 1.960 0.0 763.5 19044320 min Winter 1.400 0.0 818.5 26765760 min Winter 1.102 0.0 859.2 32887200 min Winter 0.916 0.0 892.9 36728640 min Winter 0.787 0.0 921.0 010080 min Winter 0.693 0.0 945.5 0

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Rainfall Details


Rainfall Model FEH D3 (1km) 0.258 Cv (Winter) 0.840Return Period (years) 30 E (1km) 0.287 Shortest Storm (mins) 15

Site Location F (1km) 2.449 Longest Storm (mins) 10080C (1km) -0.026 Summer Storms Yes Climate Change % +0D1 (1km) 0.384 Winter Storms YesD2 (1km) 0.368 Cv (Summer) 0.750

Time Area Diagram

Total Area (ha) 0.967

TimeFrom:

(mins)To:

Area(ha)

0 1 0.967

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Model Details


Storage is Online Cover Level (m) 10.000

Tank or Pond Structure

Invert Level (m) 9.000

Depth (m) Area (m²) Depth (m) Area (m²)

0.000 313.0 1.000 313.0

Hydro-Brake Optimum® Outflow Control

Unit Reference MD-SHE-0067-5500-8995-5500Design Head (m) 8.995

Design Flow (l/s) 5.5Flush-Flo™ CalculatedObjective Minimise upstream storage

Application SurfaceSump Available YesDiameter (mm) 67

Invert Level (m) 1.000Minimum Outlet Pipe Diameter (mm) 100Suggested Manhole Diameter (mm) 1200

Control Points Head (m) Flow (l/s)

Design Point (Calculated) 8.995 5.5Flush-Flo™ 0.280 2.0Kick-Flo® 0.597 1.6

Mean Flow over Head Range - 3.8

The hydrological calculations have been based on the Head/Discharge relationship for theHydro-Brake Optimum® as specified. Should another type of control device other than aHydro-Brake Optimum® be utilised then these storage routing calculations will beinvalidated

Depth (m) Flow (l/s) Depth (m) Flow (l/s) Depth (m) Flow (l/s) Depth (m) Flow (l/s)

0.100 1.7 1.200 2.2 3.000 3.3 7.000 4.90.200 1.9 1.400 2.3 3.500 3.5 7.500 5.00.300 2.0 1.600 2.5 4.000 3.8 8.000 5.20.400 1.9 1.800 2.6 4.500 4.0 8.500 5.40.500 1.8 2.000 2.7 5.000 4.2 9.000 5.50.600 1.6 2.200 2.8 5.500 4.4 9.500 5.60.800 1.8 2.400 3.0 6.000 4.51.000 2.0 2.600 3.1 6.500 4.7

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Event: 360 min Winter


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Summary of Results for 100 year Return Period (+40%)


StormEvent

MaxLevel(m)

MaxDepth(m)

MaxControl(l/s)

MaxVolume(m³)

Status

15 min Summer 9.413 0.413 5.3 300.2 O K30 min Summer 9.491 0.491 5.3 356.8 O K60 min Summer 9.579 0.579 5.4 420.8 O K120 min Summer 9.674 0.674 5.4 490.2 O K180 min Summer 9.730 0.730 5.4 530.8 Flood Risk240 min Summer 9.768 0.768 5.4 558.1 Flood Risk360 min Summer 9.814 0.814 5.4 591.6 Flood Risk480 min Summer 9.838 0.838 5.4 608.9 Flood Risk600 min Summer 9.849 0.849 5.5 617.0 Flood Risk720 min Summer 9.851 0.851 5.5 618.7 Flood Risk960 min Summer 9.833 0.833 5.4 605.8 Flood Risk1440 min Summer 9.799 0.799 5.4 581.1 Flood Risk2160 min Summer 9.760 0.760 5.4 552.4 Flood Risk2880 min Summer 9.722 0.722 5.4 524.9 Flood Risk4320 min Summer 9.593 0.593 5.4 431.4 O K5760 min Summer 9.482 0.482 5.3 350.1 O K7200 min Summer 9.384 0.384 5.3 278.9 O K8640 min Summer 9.298 0.298 5.3 217.0 O K10080 min Summer 9.225 0.225 5.3 163.7 O K


StormEvent

Rain(mm/hr)

FloodedVolume(m³)


Time-Peak(mins)



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StormEvent

MaxLevel(m)

MaxDepth(m)

MaxControl(l/s)

MaxVolume(m³)

Status

60 min Winter 9.651 0.651 5.4 473.5 O K120 min Winter 9.762 0.762 5.4 553.8 Flood Risk180 min Winter 9.828 0.828 5.4 602.1 Flood Risk240 min Winter 9.874 0.874 5.5 635.3 Flood Risk360 min Winter 9.933 0.933 5.5 678.3 Flood Risk480 min Winter 9.968 0.968 5.5 703.6 Flood Risk600 min Winter 9.988 0.988 5.5 718.5 Flood Risk720 min Winter 9.999 0.999 5.5 726.6 Flood Risk960 min Winter 9.997 0.997 5.5 724.7 Flood Risk1440 min Winter 9.954 0.954 5.5 693.8 Flood Risk2160 min Winter 9.894 0.894 5.5 650.2 Flood Risk2880 min Winter 9.837 0.837 5.4 608.8 Flood Risk4320 min Winter 9.650 0.650 5.4 472.9 O K5760 min Winter 9.486 0.486 5.3 353.0 O K7200 min Winter 9.343 0.343 5.3 249.1 O K8640 min Winter 9.222 0.222 5.3 161.6 O K10080 min Winter 9.124 0.124 5.2 90.2 O K

StormEvent

Rain(mm/hr)

FloodedVolume(m³)


Time-Peak(mins)


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Rainfall Details




Time Area Diagram


TimeFrom:

(mins)To:

Area(ha)

0 1 0.967

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Model Details






0.000 727.0 1.000 727.0











0.100 1.7 1.200 2.2 3.000 3.3 7.000 4.90.200 1.9 1.400 2.3 3.500 3.5 7.500 5.00.300 2.0 1.600 2.5 4.000 3.8 8.000 5.20.400 1.9 1.800 2.6 4.500 4.0 8.500 5.40.500 1.8 2.000 2.7 5.000 4.2 9.000 5.50.600 1.6 2.200 2.8 5.500 4.4 9.500 5.60.800 1.8 2.400 3.0 6.000 4.51.000 2.0 2.600 3.1 6.500 4.7

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Denbighshire LL15 1NJ Attenuation calcs 1 in 30 (BF)


File W10375-170609-ATTENUATI... Checked by JR




StormEvent

MaxLevel(m)

MaxDepth(m)

MaxControl(l/s)

MaxVolume(m³)

Status

15 min Summer 9.511 0.511 7.2 140.5 O K30 min Summer 9.609 0.609 7.2 167.6 O K60 min Summer 9.711 0.711 7.3 195.6 Flood Risk120 min Summer 9.800 0.800 7.3 220.1 Flood Risk180 min Summer 9.834 0.834 7.3 229.4 Flood Risk240 min Summer 9.840 0.840 7.3 231.1 Flood Risk360 min Summer 9.830 0.830 7.3 228.2 Flood Risk480 min Summer 9.820 0.820 7.3 225.6 Flood Risk600 min Summer 9.810 0.810 7.3 222.8 Flood Risk720 min Summer 9.799 0.799 7.3 219.6 Flood Risk960 min Summer 9.764 0.764 7.3 210.1 Flood Risk1440 min Summer 9.687 0.687 7.3 189.0 O K2160 min Summer 9.566 0.566 7.2 155.7 O K2880 min Summer 9.451 0.451 7.2 124.1 O K4320 min Summer 9.215 0.215 7.1 59.1 O K5760 min Summer 9.073 0.073 7.0 20.0 O K7200 min Summer 9.007 0.007 7.0 1.9 O K8640 min Summer 9.000 0.000 6.2 0.0 O K10080 min Summer 9.000 0.000 5.5 0.0 O K


StormEvent

Rain(mm/hr)

FloodedVolume(m³)


Time-Peak(mins)



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StormEvent

MaxLevel(m)

MaxDepth(m)

MaxControl(l/s)

MaxVolume(m³)

Status

60 min Winter 9.808 0.808 7.3 222.3 Flood Risk120 min Winter 9.924 0.924 7.4 254.1 Flood Risk180 min Winter 9.975 0.975 7.4 268.2 Flood Risk240 min Winter 9.997 0.997 7.4 274.2 Flood Risk360 min Winter 9.997 0.997 7.4 274.1 Flood Risk480 min Winter 9.971 0.971 7.4 267.0 Flood Risk600 min Winter 9.955 0.955 7.4 262.7 Flood Risk720 min Winter 9.936 0.936 7.4 257.4 Flood Risk960 min Winter 9.879 0.879 7.3 241.9 Flood Risk1440 min Winter 9.750 0.750 7.3 206.4 Flood Risk2160 min Winter 9.554 0.554 7.2 152.3 O K2880 min Winter 9.376 0.376 7.1 103.4 O K4320 min Winter 9.066 0.066 7.0 18.1 O K5760 min Winter 9.000 0.000 6.3 0.0 O K7200 min Winter 9.000 0.000 5.2 0.0 O K8640 min Winter 9.000 0.000 4.5 0.0 O K10080 min Winter 9.000 0.000 4.0 0.0 O K

StormEvent

Rain(mm/hr)

FloodedVolume(m³)


Time-Peak(mins)


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Rainfall Details




Time Area Diagram


TimeFrom:

(mins)To:

Area(ha)

0 1 0.967

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Model Details






0.000 275.0 1.000 275.0











0.100 2.2 1.200 2.9 3.000 4.4 7.000 6.60.200 2.7 1.400 3.1 3.500 4.7 7.500 6.80.300 2.9 1.600 3.3 4.000 5.0 8.000 7.00.400 2.8 1.800 3.5 4.500 5.3 8.500 7.20.500 2.8 2.000 3.7 5.000 5.6 9.000 7.40.600 2.6 2.200 3.8 5.500 5.9 9.500 7.60.800 2.4 2.400 4.0 6.000 6.11.000 2.7 2.600 4.1 6.500 6.3

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Denbighshire LL15 1NJ Attenuation calcs 40% CC (BF)






StormEvent

MaxLevel(m)

MaxDepth(m)

MaxControl(l/s)

MaxVolume(m³)

Status

15 min Summer 9.454 0.454 7.2 298.5 O K30 min Summer 9.538 0.538 7.2 353.4 O K60 min Summer 9.630 0.630 7.3 414.0 O K120 min Summer 9.726 0.726 7.3 476.8 Flood Risk180 min Summer 9.777 0.777 7.3 510.8 Flood Risk240 min Summer 9.809 0.809 7.3 531.5 Flood Risk360 min Summer 9.840 0.840 7.3 551.7 Flood Risk480 min Summer 9.846 0.846 7.3 556.1 Flood Risk600 min Summer 9.839 0.839 7.3 551.1 Flood Risk720 min Summer 9.827 0.827 7.3 543.1 Flood Risk960 min Summer 9.803 0.803 7.3 527.4 Flood Risk1440 min Summer 9.764 0.764 7.3 501.6 Flood Risk2160 min Summer 9.707 0.707 7.3 464.2 Flood Risk2880 min Summer 9.648 0.648 7.3 425.9 O K4320 min Summer 9.483 0.483 7.2 317.1 O K5760 min Summer 9.345 0.345 7.1 226.5 O K7200 min Summer 9.233 0.233 7.1 153.3 O K8640 min Summer 9.147 0.147 7.1 96.5 O K10080 min Summer 9.081 0.081 7.0 53.4 O K


StormEvent

Rain(mm/hr)

FloodedVolume(m³)


Time-Peak(mins)



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StormEvent

MaxLevel(m)

MaxDepth(m)

MaxControl(l/s)

MaxVolume(m³)

Status

60 min Winter 9.711 0.711 7.3 466.8 Flood Risk120 min Winter 9.823 0.823 7.3 540.7 Flood Risk180 min Winter 9.887 0.887 7.4 582.5 Flood Risk240 min Winter 9.928 0.928 7.4 609.4 Flood Risk360 min Winter 9.974 0.974 7.4 639.9 Flood Risk480 min Winter 9.994 0.994 7.4 653.0 Flood Risk600 min Winter 9.999 0.999 7.4 656.1 Flood Risk720 min Winter 9.994 0.994 7.4 652.8 Flood Risk960 min Winter 9.959 0.959 7.4 630.1 Flood Risk1440 min Winter 9.899 0.899 7.4 590.6 Flood Risk2160 min Winter 9.812 0.812 7.3 533.8 Flood Risk2880 min Winter 9.719 0.719 7.3 472.4 Flood Risk4320 min Winter 9.474 0.474 7.2 311.7 O K5760 min Winter 9.277 0.277 7.1 181.7 O K7200 min Winter 9.126 0.126 7.0 82.7 O K8640 min Winter 9.027 0.027 7.0 17.7 O K10080 min Winter 9.000 0.000 6.7 0.0 O K

StormEvent

Rain(mm/hr)

FloodedVolume(m³)


Time-Peak(mins)


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Rainfall Details




Time Area Diagram


TimeFrom:

(mins)To:

Area(ha)

0 1 0.967

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Model Details






0.000 657.0 1.000 657.0











0.100 2.2 1.200 2.9 3.000 4.4 7.000 6.60.200 2.7 1.400 3.1 3.500 4.7 7.500 6.80.300 2.9 1.600 3.3 4.000 5.0 8.000 7.00.400 2.8 1.800 3.5 4.500 5.3 8.500 7.20.500 2.8 2.000 3.7 5.000 5.6 9.000 7.40.600 2.6 2.200 3.8 5.500 5.9 9.500 7.60.800 2.4 2.400 4.0 6.000 6.11.000 2.7 2.600 4.1 6.500 6.3

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Appendix H – Concept Drainage Sketch

El

Ferfoot LodgeMS

House

Ash Leigh

Orchard

SubSta

TO S

UIT

DESI

GN

STAN

DARD

S

TO H

IGHW

AY C

ONS

ULTA

NTS

DESI

GN

DETA

ILS.

5200

2700

10686

7707

33

34

45

125

97

5000

5200

2700

5200

2700

126

108

107

65

57

56

46

136

2700

5200

98

135

11887

10686

77

11888

7706

88

145

117

116

167

160

161

149

154

87

01

7500

ASSU

MED

BOUN

DARY

LIN

E

PRO

POSE

DPE

DEST

RIAN

ACCE

SS.

PRO

POSE

DPE

DEST

RIAN

ACCE

SS.

PRO

POSE

D LI

DL

BRAN

DED

TOTE

M S

IGN

TOTA

L PA

RKIN

G S

PACE

S: 1

67

PLANT

AREA

PRO

POSE

DCY

CLE

PARK

ING

GAS

GO

VERN

OR

Bristol Road

Allington way

64000

20100

9000

0807

22

155

146

150

7500

21

19

7500

6318

5000

79

78 66

PRO

POSE

D RE

SIDE

NTIA

L

DEVE

LOPE

MEN

T

PRO

POSE

D AC

CESS

/EG

RESS

9000

10380

7270

7195

9230

20

©



Appendix I – Maintenance Schedules

SuDS Maintenance Schedule

File Ref: Permeable Paving - SuDS Maintenance

Ref. Table 20.15, CIRIA C753 ‘The SuDS Manual

Maintenance Schedule

Required Action Typical Frequency

Regular maintenance

Brushing and vacuuming (standard cosmetic sweep over whole surface)

Once a year, after autumn leaf fall, or reduced frequency as required, based on site-specific observations of clogging or manufacturer’s recommendations – pay particular attention to areas where water runs onto pervious surface from adjacent impermeable areas as this area is most likely to collect the most sediment

Occasional maintenance

Stabilise and move contributing and adjacent areas As required

Removal of weeds or management using glyphospate applied directly into the weeds by an applicator rather than spraying

As required – once per year on less frequently used pavements

Remedial actions

Remediate any landscaping which, through vegetation maintenance or soil slip, has been raised to within 50mm of the level or the paving

As required

Rehabilitation of surface and upper substructure by remedial sweeping

Every 10 to 15 years or as required (if infiltration performance is reduced due to significant clogging)

Monitoring

Inspect for evidence of poor operation and / or weed growth – if required, take remedial action

Three-monthly, 48hr after large storms in first six months

Inspect silt accumulation rates and establish appropriate brushing frequencies

Annually

Monitor inspection chambers Annually

Operation and Maintenance Requirements for Permeable Paving


File Ref: Permeable Paving - SuDS Maintenance

The maintenance requirements detailed above are to be undertaken by the site owner.

Name: ……………………………………………….

Position: ……………………………………………….

Date: ………………………………………………. Signed on behalf Of the site owner ……………………………………………….


File Ref: Tank - SuDS Maintenance

Operation and Maintenance Requirements for Attenuation Storage

Tanks

Ref. Table 21.3, CIRIA C753 ‘The SuDS Manual’

The maintenance requirements detailed above are to be undertaken by the site owner.

Name: ……………………………………………….

Position: ……………………………………………….

Date: ………………………………………………. Signed on behalf Of the site owner ……………………………………………….

Maintenance Schedule

Required Action Typical Frequency

Regular maintenance

Inspect and identify any areas that are not operating correctly. If required, take remedial action

Monthly for 3 months, then annually

Remove debris from the catchment surface (where it may cause risks to performance) Monthly

For systems where rainfall infiltrates into the tank from above, check surface of filter for blockage by sediment, algae or other matter; remove and replace surface infiltration medium as necessary

Annually

Remove sediment from pre-treatment structures and/ or internal forebays Annually, or as required

Remedial actions Repair/rehabilitate inlets, outlet, overflows and vents As required

Monitoring

Inspect/check all inlets, outlets, vents and overflows to ensure that they are in good condition and operating as designed

Annually

Survey inside of tank for sediment build-up and remove If necessary

Every 5 years or as required

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