Flood Investigation Report- Kelleythorpe and Driffield Showground During winter 2012 - 2013

Revision Schedule

East Riding of Yorkshire Council Flood Investigation Report Kelleythorpe and Driffield Showground during Winter 2012/2013

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Rev Date Details Author Checked and Approved By 0.1 1 Initial Draft AMM 0.2 11/10/13 Revised Draft GP/AMM

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Flood Investigation Report- Kelleythorpe and Driffield Showground During winter 2012 - 2013

Copyright Notice

Maps in this report are reproduced from Ordnance Survey material with the permission of Ordnance Survey on behalf of Her Majesty’s Stationery Office Crown copyright 2008.

Unauthorised reproduction infringes Crown copyright and may lead to prosecution or civil proceedings. East Riding of Yorkshire Council 100023383.

Records of the public sewer system included are a facsimile of the statutory record provided by Yorkshire Water Services. For the purposes of this report minor sewers and other non relevant data have been omitted from the plans for clarity. The statutory public sewer record is held by Yorkshire Water Services Ltd.

Acknowledgement

East Riding of Yorkshire Council would like to thank members of the Driffield Agricultural Society (DAS), for their co-operation and assistance throughout this investigation.

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Flood Investigation Report- Kelleythorpe and Driffield Showground During winter 2012 - 2013

Table of Contents Page

Lead Local Flood Authority and Responsibilities ...... 5 Relevant Flood Risk Management Authorities...... 5 Abbreviations: ...... 7 1. Executive Summary ...... 8 1.1 Location of Flooding ...... 9 2. The Drainage System ...... 12 2.1 The Land Drainage System ...... 12 2.2 Flooding History ...... 13 3. The Flooding Event ...... 14 3.1 Conditions before the event ...... 14 3.2 The Event ...... 15 3.3 Causes and Investigation Findings ...... 18 4. Conclusions ...... 23 5. Recommendations ...... 24 Useful Links and Contact Details: ...... 25 Appendices: ...... 26 Appendix 1 Monthly rainfall and groundwater levels ...... 27 Appendix 2 Aerial photograph of event ...... 28 Appendix 3 Groundwater levels from 2010 to present ...... 29 Appendix 4 Historic groundwater levels ...... 30 Appendix 5 Geology of the area ...... 31 Appendix 6 Location plan (A3) ...... 32 Appendix 7: Showground culvert location ...... 33

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Flood Investigation Report- Kelleythorpe and Driffield Showground During winter 2012 - 2013

Lead Local Flood Authority and Responsibilities

East Riding of Yorkshire Council, as the Lead Local Flood Authority (LLFA), has a responsibility under Section 19 of the Flood and Water Management Act 2010 to investigate significant flood incidents in its area. Section 19 states:

(1) On becoming aware of a flood in its area, a lead local flood authority must, to the extent that it considers it necessary or appropriate, investigate —

(a) which risk management authorities have relevant flood risk management functions, and

(b) whether each of those risk management authorities has exercised, or is proposing to exercise, those functions in response to the flood.

(2) Where an authority carries out an investigation under subsection (1) it must—

(a) publish the results of its investigation, and

(b) notify any relevant risk management authorities.

(3) The LLFA has lead responsibility for managing the risk of flooding from surface water, groundwater and ordinary water courses.

This report has been prepared by the East Riding of Yorkshire Council in its role as LLFA in response to extensive flooding which affected properties in Gott Close, Montgomery Square, Driffield Rugby Club and Driffield Showground in the winter of 2012-13.

This report provides details and an overview of flooding that has occurred, describes the conditions which led to the flooding, considers the response to the flooding thus far and makes technical recommendations for the flood risk authorities concerned.

Relevant Flood Risk Management Authorities

The relevant parties that have relevant flood risk management responsibilities are:

East Riding of Yorkshire Council East Riding of Yorkshire Council is the Lead Local Flood Authority responsible for managing flood risk from surface runoff, groundwater and ordinary watercourses, development of a Local Flood Risk Strategy, Asset Plans and Investigations under the Flood & Water Management Act 2010. East Riding of Yorkshire Council is also the Highway Authority with responsibility for highway drainage under the Highway Act 1980.

Environment Agency Responsible for managing the Flood risk from main rivers, the sea and reservoirs including coastal erosion risk management, permissive powers to maintain Main Rivers, Strategic Overview over all forms of flooding and development of a national Flood Risk Strategy.

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Flood Investigation Report- Kelleythorpe and Driffield Showground During winter 2012 - 2013

Yorkshire Water Yorkshire Water Services is the statutory sewerage undertaker for the Yorkshire region with a duty to effectually drain sewers pursuant to the Water Industries Act 1991.

Additionally:

Riparian Landowners

Riparian landowners are those who own land adjoining a watercourse and have certain responsibilities, including the following:

• They must maintain the bed and banks of an open watercourse, and also the trees and shrubs growing on the banks. • They must clear any debris, even if it did not originate from their land, this debris may be natural or man-made. • They must keep any structures that they own clear of debris. These structures include culverts, trash screens, weirs and mill gates.

If they do not carry out their responsibilities, they could face legal action under the Land Drainage Act 1991. Details of a riparian landowners responsibilities can be found in “Living on the Edge” published by the Environment Agency.

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Flood Investigation Report- Kelleythorpe and Driffield Showground During winter 2012 - 2013

Abbreviations:

AOD Above Ordnance Datum

CCTV Survey using Closed Circuit Television camera travelling through a pipe or culvert.

CSO Combined Sewer Overflow

DAS Driffield Agricultural Society

EA Environment Agency

ERYC East Riding of Yorkshire Council

GWL Ground Water Level m metres

MH Manhole

YWS Yorkshire Water Services Ltd

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Flood Investigation Report- Kelleythorpe and Driffield Showground During winter 2012 - 2013

1. Executive Summary

The flooding in Kelleythorpe was unusual in that it was not as a result of a single rainfall event but due to the cumulative effect of rainfall over a prolonged period. During 2012, persistent wet weather (second wettest year on record in England, see Appendix 1) resulted in exceptionally high water levels in the whole area and in particular the River Hull catchment which includes the Driffield area.

With high water levels in the River Hull, combined with elevated groundwater levels in the chalk, the groundwater was not able to drain away into the river and so remained at elevated levels for some time. This led to many seasonal springs rising across the area and exceptionally high flows in various watercourses on the Wolds, with surface and property flooding in many places including parts of Driffield and Kelleythorpe, as well as the inundation of the foul sewer system. Significant areas of farmland were also flooded both in the upper catchment area and downstream of Driffield.

The Gipsey Race is a largely open watercourse through Kelleythorpe draining a large catchment area to the west of Driffield, into the Driffield Beck. The Race is often dry for much of the year in common with other such streams on the Wolds. The exceptionally high flows in the Gipsey Race in Driffield during late 2012 led to flooding at the rear of Montgomery Square/Gott Close and across Driffield Showground and Driffield Rugby Club.

Immediately downstream of Montgomery Square the Race crosses the A614 in twin 900mm diameter culverts. It then flows across the showground in an open channel with three field crossings, one bridge and two separate single 900mm diameter culverts. The Race then crosses under an old railway line, which crosses the showground, and then a 300m long section of various sizes of culvert, and discharges into an open section before crossing under Beverley Road and joining Driffield Beck just below the Hallimanwath Bridge.

In early December 2012 the showground began to flood, then on the afternoon of 14 December buildings on the showground flooded when the culvert across the eastern side of the showground was overwhelmed. The showground was free of surface flooding by 25 January as a result of intervention by the Environment Agency who provided pumps and sandbags, a general reduction in water levels, and the efforts of the Driffield Agricultural Society (DAS) staff who dug a drainage channel across the flooded area.

On 27 December Glenfield Care Home in Montgomery Square contacted ERYC to report the water levels in the Gipsey Race which, in their view, were threatening to flood the property. ERYC officers visited the site and determined that at the time of the visit no further action was required.

During the day on 28 December the water levels continued to rise and ERYC deployed sandbags in an effort to protect the Care Home and portable toilets were delivered as downstairs toilets in the Home were unusable due to the inundation of the public sewer system. Also the water level reached two properties in Montgomery Square causing considerable damage inside the properties, and properties in Gott Close were also affected. Significant areas of farmland were also flooded in the Wolds area at this time.

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Flood Investigation Report- Kelleythorpe and Driffield Showground During winter 2012 - 2013

Various options to reduce the flood risk are considered in this report’s recommendations.

1.1 Location of Flooding

Kelleythorpe, including Gott Close ,Montgomery Square, the Driffield Rugby Club and Driffield Showground are situated to the south west of Driffield.

Location of Kelleythorpe and Driffield Showground

An open watercourse known as the Gipsey Race, which drains agricultural land to the west, runs past Gott Close, Montgomery Square and across the rugby field and the showground, where it enters a culvert before discharging into the Driffield Beck which in turn discharges into the River Hull.

Area flooding, with gardens and roads affected by surface water standing or flowing across the surface, but not inside the properties, occurred near properties in Gott Close and Montgomery Square as well as extensive flooding of the showground and rugby field. Some properties on Montgomery Square and buildings on the showground were flooded internally. Properties in Gott Close suffered area flooding to gardens and there was some under floor flooding. At the same time, large areas of agricultural land both upstream and downstream of the area were also flooded.

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Flood Investigation Report- Kelleythorpe and Driffield Showground During winter 2012 - 2013

Photo 1: Showground and rugby club.

At the same time extensive areas of farmland upstream to the west and downstream to the east were also flooded.

Photo 2: Farmland to the west of Kelleythorpe Industrial Estate.

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Flood Investigation Report- Kelleythorpe and Driffield Showground During winter 2012 - 2013

Photo 3: Farmland to the south and east of Driffield.

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Flood Investigation Report- Kelleythorpe and Driffield Showground During winter 2012 - 2013

2. The Drainage System

2.1 The Land Drainage System

Driffield is within the River Hull catchment, the land drainage from the Wolds to the west of the town which drains into the Driffield Beck via Elmswell Beck, Little Driffield Beck and the Gipsey Race.

The Gipsey Race is a typical chalk stream in that water is only seen to flow in the bed of the stream following wet weather, mainly during the winter months, and is known to be dry in the summer months, although ground water will be flowing underground towards the river system.

The Race is an open watercourse which passes Gott Close and Montgomery Square, through a highway culvert under Kelleythorpe Road (Wadsworth Road) and the A614, in twin 900mm diameter culverts, emerging along the southern edge of the rugby field. It flows into an open watercourse, crossing the western part of the showground before entering a culvert under the old railway line, which crosses the showground to the eastern boundary, and joins Driffield Beck after passing under Beverley Road adjacent to the Hallimanwath Bridge. (See Appendix 2)

At the time of the flooding there were three crossings over the Race on the rugby field, one an old timber bridge has subsequently been removed, the other two are single 900mm pipes.

The culvert section of the Race under the eastern area of the showground (see figure 2 below) was formerly an open watercourse and had been piped in sections largely during the 1960s. At the time of the flood it was believed to be a single 700mm diameter pipe.

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Flood Investigation Report- Kelleythorpe and Driffield Showground During winter 2012 - 2013

Figure 2: Location of Driffield Showground culvert

A CCTV inspection after the events revealed buried manholes and a variety of pipes of differing size, some in poor structural condition. From Manhole 1 to the uncharted Manhole 1a and on to Manhole 2 is a 600mm diameter pipe; from Manhole 2 to Manhole 3 is a 700mm diameter pipe; from Manhole 3 to the uncharted Manhole 4 are twin 600mm diameter pipes; from Manhole 4 to the outfall is a 700mm diameter culvert. From discussions with DAS it is understood that the culverting works were carried out at various times during the 1960s.

At the time of the CCTV inspection, some partial obstructions were located and removed. It has not been possible to determine whether these obstructions were present before the event or built up during the event, however it is considered most likely that they built up during the flooding event.

2.2 Flooding History

There is a history of the Race overtopping its banks near Gott Close and Montgomery Square during very wet weather, usually in the winter months, but it is believed that properties were affected only in 2007, which was an exceptional event, and again in 2012/13.

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Flood Investigation Report- Kelleythorpe and Driffield Showground During winter 2012 - 2013

3. The Flooding Event

3.1 Conditions before the event

Following an exceptionally dry winter and spring in 2012 which gave rise to drought orders being drafted, a wet summer followed with persistent heavy rainfall in late November and early December. Reportedly the second wettest year on record in England, this resulted in exceptionally high water levels in the whole of the River Hull catchment (See Appendix 1: Rainfall and ground water levels).

With elevated groundwater levels combined with sustained high water levels in the River Hull, the groundwater was not able to drain away into the river and so levels remained elevated for some time. This also led to many springs appearing across the area with exceptionally high flows in various watercourses on the Wolds, particularly the Gipsey Race, and surface flooding on agricultural land in several locations. The elevated groundwater levels were the major contributor to the flooding. The Race, a typical chalk stream, is dry much of the year with a flow only during wet weather. The open section across the rugby field was in poor condition with bushes growing in the bed.

While the condition of the open watercourse on the rugby field and of the culvert on the showground may have contributed to the event, from the information available, ERYC concludes that property flooding would not have resulted in less extreme conditions.

Appendix 1 shows the rainfall and groundwater levels during 2012, with the dry winter period followed by a wetter than average summer and a very high rainfall in April, June, November and December. This corresponds with the rapid rise in groundwater levels in May/June and December.

Appendix 3 shows the groundwater levels in the chalk near Driffield between January 2010 and April 2013. It shows the normal fluctuations in the groundwater levels through 2010 and into winter 2010/11, then the levels falling all through 2011, which is unusual. There were exceptionally low groundwater levels in March 2012 following an unusually dry winter, before the levels rose rapidly during May 2012, then again in December 2012 following periods of heavy rainfall. This illustrates the exceptional circumstances which led to high groundwater levels and high flows in watercourses which in turn led to the flooding.

Appendix 4 shows the historic groundwater levels in the EA borehole at Tancred Pit north of Kilham from 1979 to 2013. This shows the pattern of the water levels during this 30 year period. This proves that levels were similar to the winter of 2012/13 in 1979, 1980 and 1981, then very low during the period from 1990 to 1993, returning to high levels in 2001, 2003 and in 2012/13.

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Flood Investigation Report- Kelleythorpe and Driffield Showground During winter 2012 - 2013

3.2 The Event

The water levels in the Gipsey Race rose throughout December 2012, a not unusual situation following wet weather, and even when the Race overtopped its banks and flooded the private road in Montgomery Square, the residents were not unduly alarmed as this had happened previously. Driffield Beck was also at a high level and had overtopped its banks in places causing flooding to farmland.

During December the showground suffered surface flooding along the line of the culvert, which was originally an open watercourse culverted in the 1960s, and along its southern and eastern boundaries. This also affected the highway footpath adjacent to the site. On 14 December 2012 buildings on the showground were flooded internally.

Photo 1: Flooding on the showground

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Flood Investigation Report- Kelleythorpe and Driffield Showground During winter 2012 - 2013

Photo 2: Showground offices.

The flow in the Race exceeded the capacity of the culvert across the eastern area of the showground. On inspection the culvert appeared to be running full.

The DAS staff removed the last section of the culvert at the outfall in an attempt to increase the discharge. They also excavated a channel from the flooded area of the site towards the open watercourse at the end of the culvert in an attempt to drain the area more effectively and to protect their buildings.

In January the EA deployed two 150mm diameter pumps to transfer water from upstream of the culvert into the Driffield Beck some 300m away across the showground. Sandbags were also deployed to protect the buildings and the channel was extended farther across the site in an attempt to drain away the water more quickly to protect the buildings.

As a result of a second call from the Care Home in Montgomery Square, ERYC deployed sandbags to protect the property as water escaped from the Race. At this time, the foul sewer system was inundated with surface water and the Care Home was using chemical toilets provided by ERYC because the Home’s downstairs toilets were unusable.

At the same time, the flood water reached other properties in Montgomery Square causing internal flooding to the ground floors. Water was also found under the floors of some properties in Gott Close while others also suffered garden flooding. The public highway at Kelleythorpe roundabout was also flooded.

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Flood Investigation Report- Kelleythorpe and Driffield Showground During winter 2012 - 2013

Photo 3: Rear of properties in Montgomery Square, January 2012.

Photo 4: Front of properties in Montgomery Square showing the location of the Gipsey Race at the tree line.

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Flood Investigation Report- Kelleythorpe and Driffield Showground During winter 2012 - 2013

3.3 Causes and Investigation Findings

Groundwater levels were extreme following the second wettest year on record in England with the rainfall concentrated into the latter part of the year.

Once the flow in the Race exceeded the capacity of the culverted section across the showground, flood water started to flow over the surface of the showground, eventually flooding the showground offices.

By the time the properties in Gott Close and Montgomery Square were affected, the flow in the Race had exceeded the capacity of the downstream section and flood water was flowing across the A614 and onto Kelleythorpe roundabout. At the same time Driffield Beck, east of Hallimanwath Bridge had overtopped its banks causing flooding to agricultural land.

As the flow levels started to recede, the water stopped flowing across the A614 but was still flowing across the surface of the showground, backing up from the culvert entrance at the old railway line. At this time water was also escaping from the culvert entrance on the downstream side of the old railway line (which is now the access road across the showground) and around the blockwork (see Photo 6), which had been used to seal the end of the old railway crossing and continuation pipe. The old culvert is between the open section and Manhole 1 (see Figure 2: culvert location plan). The location of this manhole was unknown previous to the flooding.

Photo 5: Downstream end of the old railway culvert during the event.

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Flood Investigation Report- Kelleythorpe and Driffield Showground During winter 2012 - 2013

Photo 6: Downstream end of the old railway culvert after the event.

An inspection by ERYC engineers of the Race at Montgomery Square during the flooding identified debris lodged under the private road bridge. This was removed by ERYC on a Without Prejudice basis. Subsequent inspection of the culvert across the showground after the water had subsided located a partial obstruction in Manhole 1 near the railway crossing. This was removed by the ERYC (Without Prejudice) as part of the investigation. It is unclear when this obstruction built up, either before or during the flooding event, however inspection of the outflow from the culvert indicated that the culvert was running full.

An inspection of the open watercourse across the rugby field found that there was shrubbery growing in the bed and the bed level was above the A614 culvert invert, both of which will have restricted the flow. Once the water levels had subsided, making it safe to carry out the works, the bed of the open section was cleaned out by the Driffield Agricultural Society (DAS) and the timber bridge removed. The culvert under the A614 was cleaned by ERYC.

Once the water levels had subsided, a full CCTV survey was varied out as part of ERYC’s investigation of the culverted sections of the Race across the showground, revealing three buried manholes. These three manholes were unknown before the survey. DAS staff exposed the manholes to allow the survey to be completed. This showed there was a partial obstruction between Manhole 1 and Manhole 1a, and poor construction of Manhole 1a. The third buried manhole, referred to as Manhole 4 on Appendix 7, was exposed by DAS to allow the survey to be completed. The survey identified obstructions, which were removed.

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Flood Investigation Report- Kelleythorpe and Driffield Showground During winter 2012 - 2013

Photo 7: CCTV image of restriction in Manhole 1a.

The culvert across the showground varies in size with some lengths of 600mm diameter, some of 700mm diameter and one section of twin 600mm diameter pipes. There was also a short section of 600mm diameter pipe which appears to be an old repair of a 700mm diameter section.

The inlet to the culvert had an inadequate screen to prevent debris entering the culvert – DAS plans to replace it with a purpose-made trash screen. Had this type of screen been in place at the time, it is likely that some of the obstructions would not have entered the culvert.

Photo 8: Culvert entrance showing the crude trash screening.

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Flood Investigation Report- Kelleythorpe and Driffield Showground During winter 2012 - 2013

Photo 9: Poor structural condition of pipes at the eastern end of the culvert showing the danger of collapse of the structure under the surface load, even though the flow is not compromised.

Photo 10: Open section in rugby field in January during the event.

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Flood Investigation Report- Kelleythorpe and Driffield Showground During winter 2012 - 2013

Photo 11: Open watercourse across the rugby field after clearing by DAS in March.

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Flood Investigation Report- Kelleythorpe and Driffield Showground During winter 2012 - 2013

4. Conclusions

ERYC, as LLFA has investigated the flooding at Kelleythorpe and Driffield during December 2012 and January 2013 using its powers under Section 19 of the Flood and Water Management Act 2010 and has concluded the following:

The overriding cause of the flooding was the exceptional rainfall during the year leading up to the flooding, giving rise to extremely high groundwater levels, rising springs and high levels in watercourses, particularly Gipsey Race.

While the elevated groundwater levels were the major cause of the flooding, the condition of the open watercourse on the rugby field and of the culvert on the showground restricted flows. An additional factor was that the receiving watercourse (Driffield Beck) was also at a high level.

ERYC concluded that the condition of the watercourse and the showground culvert would not result in the flooding of property in less extreme conditions.

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Flood Investigation Report- Kelleythorpe and Driffield Showground During winter 2012 - 2013

5. Recommendations

The investigation has identified a number of measures that could improve flood resilience and these are set out in the following recommendations:

Recommendation 1

DAS is to remove restrictions to flow identified by the CCTV survey undertaken by ERYC as part of its investigation, and replace the trash screen. DAS has already made a start on carrying out this work.

Recommendation 2

A maintenance schedule for the Gipsey Race and culvert, where they cross the rugby field and showground, are to be prepared by DAS and implemented, supported by ERYC in an advisory capacity.

Recommendation 3

DAS to undertake culvert improvements on a rolling programme to be agreed with ERYC in its role as LLFA. ERYC will advise DAS on possible funding sources for the work, and assist with any bids for funding.

Recommendation 4

ERYC will carry out a feasibility study of the construction of an overflow pathway from the Gipsey Race to an alternative outlet. Subject to its being deemed feasible, then funding should be sought.

Recommendation 5

Kirkburn parish council should consider preparing a Local Emergency Plan, in consultation with the Gott Close Residents Association and DAS, with a view to providing improved response in the case of further flooding events in the future. ERYC response is based on continuous monitoring of rainfall and water levels in critical watercourses with plans in place to deploy sandbags and/or ERYC mobile pumps as required.

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Flood Investigation Report- Kelleythorpe and Driffield Showground During winter 2012 - 2013

Useful Links and Contact Details:

Lead Local Flood www.eastriding.gov.uk Authority East Riding of Yorkshire 01482 887700 [email protected] Council County Hall Beverley East Riding of Yorkshire HU17 9BA

Statutory Sewerage www.yorkshirewater.co.uk Undertaker Yorkshire Water Services Ltd 0845 1242424 Western House, Halifax Road, Bradford BD6 2SZ

Environment Agency General Enquiries www.environmentagency. Dales Area Office 08708 506506 gov.uk Coverdale House (Mon-Fri, 8am-6pm) Amy Johnson Way Clifton Moor Incident Hotline York 0800 807060 (24hrs) YO30 4UZ

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Flood Investigation Report- Kelleythorpe and Driffield Showground During winter 2012 - 2013

Appendices:

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Flood Investigation Report- Kelleythorpe and Driffield Showground During winter 2012 - 2013

Appendix 1 - Monthly Rainfall and Groundwater Levels Monthly Rainfall January 2012 to April 2013

mm

Groundwater levels January 2012 to April 2013, ground level is 12m A.O.D.

Ground Water Levels (GWL m

The above data shows the delay in response as the rainfall percolates through the ground and then drains away slowly, and the cumulative effect of the rainfall on groundwater levels.

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Flood Investigation Report- Kelleythorpe and Driffield Showground During winter 2012 - 2013

Appendix 2 - Aerial photograph of event

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Flood Investigation Report- Kelleythorpe and Driffield Showground During winter 2012 - 2013

Appendix 3 - Groundwater levels from 2010 to present

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Flood Investigation Report- Kelleythorpe and Driffield Showground During winter 2012 - 2013

Appendix 4 - Historic groundwater levels

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Flood Investigation Report- Kelleythorpe and Driffield Showground During winter 2012 - 2013

Appendix 5 - Geology of the Area

The Great Wold Valley contains the Gypsey Race, the only, albeit intermittent, surface stream on the high Wolds. Although there are many springs and other smaller streams within the overall area, these are principally concentrated around the edges of the Wolds, where the chalk meets the clay of the surrounding lowlands - as in the Kirkburn-Southburn-Eastburn-Driffield area.

The chalk of the Wolds is generally highly permeable, the water migrating principally through the fissure system and being stored mainly in this system. It is not a single aquifer but a complex system due to the fractured nature of the rock. The fact that this takes place underground makes modelling of the flow through the ground very difficult.

As a result of the chalk resting upon the underlying clay formation any water that enters the chalk is trapped in the aquifer until it reaches ground level, either at a spring or through the bed / bank of a watercourse, such as the Gypsey Race.

Geology of the chalk Wolds

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Flood Investigation Report- Kelleythorpe and Driffield Showground During winter 2012 - 2013

Appendix 6 - Location plan (A3)

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Flood Investigation Report- Kelleythorpe and Driffield Showground During winter 2012 - 2013

Appendix 7 - Showground culvert location

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