Hatfield Moor SSSI

Water Level Management Plan

October 2006

Environment Agency Hatfield Moor SSSI Water Level Management Plan Final Report [October 2006]

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© Environment Agency October 2006

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This document was prepared for the Environment Agency by Jacobs UK Ltd in association with ESI Ltd under the Framework for Ad Hoc Groundwater Technical Services.

Environment Agency Hatfield Moor SSSI Water Level Management Plan Final Report [October 2006]

WATER LEVEL MANAGEMENT PLAN: REVIEW SIGN-OFF SHEET

GENERAL DETAILS

Site Name: Hatfield Moor SSSI Region/Area: Midlands Region/Lower Trent Area

Agency Project Manager: Lucy Bolton

ENGLISH NATURE/NATURAL ENGLAND & ENVIRONMENT AGENCY AGREEMENT TO REVIEWED WATER LEVEL MANAGEMENT PLAN

“I confirm that I agree with the findings and recommendations of this reviewed Water Level Management Plan. I confirm that I believe that the actions set out would achieve the water level management appropriate for securing the favourable condition of the affected units of the SSSI”

Position Name Signature Date

English Nature / Natural Tim Kohler England Conservation Officer

Environment Agency Area Paul Lockhart Flood Risk Manager

"I have reviewed this Water Level Management Plan and confirm that I support its recommendations"

Name

Signature ......

Date …………………………………………...

Position

Organisation Hatfield Chase Internal Drainage Board

Name

Signature ......

Date …………………………………………...

Position

Organisation Yorkshire Water

Environment Agency Hatfield Moor SSSI Water Level Management Plan Final Report [October 2006] Contents

EXECUTIVE SUMMARY...... I

1 PURPOSE OF THE PLAN...... 1 1.1 WATER LEVEL MANAGEMENT PLANS ...... 1 1.2 WATER LEVEL MANAGEMENT PLAN REVIEW ...... 1 1.3 PARALLEL STUDIES ...... 3 2 SITE DETAILS ...... 3

3 SITE LOCATION...... 4

4 NATURE CONSERVATION INTERESTS...... 6 4.1 NATURE CONSERVATION DESIGNATIONS ...... 6 4.2 HATFIELD MOOR SSSI – NOTIFIED HABITATS ...... 8 4.3 SPECIES OF NATURE CONSERVATION IMPORTANCE...... 12 4.4 CONSERVATION AIMS ...... 13 4.5 CONSERVATION MANAGEMENT ...... 14 5 OTHER LAND USE ...... 15

6 HYDROLOGY ...... 17 6.1 BACKGROUND ...... 17 6.2 TOPOGRAPHY...... 18 6.3 GEOLOGY AND SOILS...... 18 6.4 CURRENT HYDROLOGICAL REGIME...... 19 6.5 CURRENT SITE CONDITIONS...... 26 7 WATER QUALITY ...... 30

8 CULTURAL HERITAGE ...... 30

9 WATER LEVEL MANAGEMENT OBJECTIVES ...... 31

10 CONSTRAINTS AND IMPACTS ON ADJACENT GROUND...... 32 10.1 PRACTICAL AND FINANCIAL CONSTRAINTS ...... 32 10.2 ENVIRONMENTAL CONSTRAINTS AND OPPORTUNITIES ...... 33 11 ALTERATION TO INFRASTRUCTURE & PROCEDURES...... 34

12 OTHER PROPOSED ACTION ...... 35

13 CONTINGENCY MEASURES ...... 36

14 UNRESOLVED ISSUES ...... 37

15 OTHER MATTERS ...... 37

16 CONSULTEES...... 38 16.1 WATER LEVEL MANAGEMENT PLAN CONSULTATION ...... 38 16.2 PROJECT BOARD ...... 41 REFERENCES AND BIBLIOGRAPHY ...... 44

Environment Agency Hatfield Moor SSSI Water Level Management Plan Final Report [October 2006] Appendices

A HATFIELD MOOR SSSI CITATION B AVAILABLE MONITORING DATA C CULTURAL HERITAGE D SCOPE OF PROPOSED HYDROLOGICAL REVIEW

List of Tables

Table 1.1 Parallel studies 3 Table 4.1 Species of nature conservation importance 12 Table 4.2 Humberhead Peatlands NNR site objectives 14 Table 6.1 Uncertainties and suggested further study 26 Table 6.2 Summary of comments made during the last condition assessment for Hatfield 27-28 Moor SSSI (compiled 1 April 2006) Table 9.1 Key targets and actions for water level management 31-32 Table 11.1 Potential options for water level management at Hatfield Moor SSSI 34-35 Table 12.1 Programme of actions required 36 Table 16.1 Organisations within the Communication Plan 38 Table 16.2 Consultation responses 38-39

List of Figures

Figure 1.1 Water Level Management Plan review process 2 Figure 3.1 Location of Hatfield Moor SSSI 5 Figure 4.1 Conservation designations 7 Figure 4.2 Distribution of broad habitat types, SSSI units and key habitat features 11 Figure 4.3 Cross section of an intact lowland raised peat bog (from Morgan-Jones et al 8 2005) Figure 4.4 Cross section of a degraded lowland raised peat bog (from Morgan-Jones et al 9 2005) Figure 5.1 Key land use features within and adjacent to Hatfield Moor SSSI 16 Figure 6.1 Hydrological features within Hatfield Moor SSSI 24 Figure 6.2 Conceptualisation of hydrology at Hatfield Moor SSSI 26 Figure 6.3 Site condition 29

Environment Agency Hatfield Moor SSSI Water Level Management Plan Final Report [October 2006] Executive summary Purpose of the plan The Government has set a target to bring 95 per cent of all nationally important wildlife sites to favourable condition by 2010. A Water Level Management Plan (WLMP) provides a means of balancing and integrating the water level requirements for a range of activities within a Site of Special Scientific Interest (SSSI). It comprises a written statement that outlines the objectives for a SSSI and how they may be achieved. The Environment Agency has the primary responsibility, as the operating authority, for bringing 64 SSSIs in England back to favourable condition, by achieving appropriate water level management. A revised WLMP will be produced for each site with an action plan to implement the WLMP.

Hatfield Moor SSSI is identified as a priority site nationally and water level management is essential to delivering favourable condition. There is no existing WLMP for Hatfield Moor SSSI and this is the first plan produced for this site.

Site details Hatfield Moor SSSI is located approximately 10km east of Doncaster in the Humberhead Levels. The moor is a remnant of a once extensive lowland raised bog and constitutes the second largest lowland raised peat bog in England. The SSSI, which covers an area of 1400ha is split into 24 units, and includes four broad habitat types: bogs, rivers and streams (lowland ditch system), standing open water and canals and lowland acid grassland. Bogs form the dominant habitat. The importance of Hatfield Moor is reflected in its nature conservation designations. As well as being a SSSI, parts of Hatfield Moor are also designated as a Special Area of Conservation (SAC) under the EC Habitats Directive, Special Protection Area (SPA) under the Birds Directive and a National Nature Reserve (NNR).

Conservation objectives Natural England has set conservation objectives to restore the designated habitats to a favourable condition. Attributes within the favourable condition table for the site include: • Active peat formation: vegetation composed predominantly of peat forming plants to achieve a net accumulation of peat. • Water availability to lowland ditch system. • Water quality of the lowland ditch system.

Current site management Natural England is currently undertaking works across a large proportion of the site to bring the degraded raised bog into a favourable condition. Written plans for conservation management and restoration of Hatfield Moor SSSI are being developed by Natural England but were not available during preparation of this WLMP. Natural England own and manage the majority of Hatfield Moor SSSI although there are several areas in private ownership. Natural England is currently negotiating management agreements with some SSSI landowners. Hatfield Chase IDB maintains its drainage network. Responsibility for the maintenance of other ditches rests with the riparian owner.

Environment Agency Hatfield Moor SSSI Water Level Management Plan Final Report [October 2006] i Current site conditions Following the most recent condition assessment of the SSSI in July 2004, half of the site is considered to be either unfavourable declining or unfavourable no change, and without intervention, these areas will become progressively worse. Management measures are in place for the other half of the site which is considered to be unfavourable recovering. The main reasons given for unfavourable condition are peat extraction, drainage and inappropriate scrub control.

Hydrological regime Natural lowland raised bogs are rainwater fed and typically independent of the underlying groundwater. Some bogs develop on more permeable drift (as seems to be the case with parts of Hatfield Moor). In such situations peat fibres can block the pore spaces of the underlying material, thus creating an impermeable layer at the base of the bog. However, such blockage does not always occur and some bogs show hydrological continuity with underlying aquifers. Under a natural system, the main loss of water from the system is through evaporation and transpiration where there are vascular plants. However, when bogs are degraded, there is a change in the components of the water balance and losses through surface water drainage and potentially vertical seepage may become important.

Peat has been extracted from Hatfield Moor since the 14th Century. Initially this was small-scale hand cutting to provide fuel. However, in the 1960s, larger scale extraction began to meet horticultural demands for peat. During this process, vegetation was removed, and drainage channels were cut. These fed into deeper drains to remove water from the site and into the Isle of Axholme pumped drainage system. Surface water leaving Hatfield Moor is pumped via high level carriers (main rivers) to Keadby Pumping Station where it is discharged into the River Trent. As part of its restoration works, Natural England has installed peat bunds and several sheet pile dams (with penstocks) at the site to hold water levels high. The primary objective of these works is to hold water levels at or around the surface level.

The hydrological regime of the SSSI is complex and there are several uncertainties which need to be addressed through further study. There are several components of a water balance which need to be understood including groundwater interactions, surface water drainage and the influence of climate on water availability. In particular, there are some uncertainties concerning the hydrological effect of the restoration works on surrounding land.

Mott MacDonald (2006) is currently undertaking field studies and analyses to demonstrate the significance of groundwater abstraction at Boston Park and Hatfield Woodhouse as part of the Yorkshire Water Services AMP 4 study. Within this study they are developing a water balance for Hatfield Moor. This water balance study is in its early stages and will be developed further as more data is collected and analysed. The Environment Agency will continue to collaborate with Mott MacDonald to develop this water balance using data obtained through monitoring.

Environment Agency Hatfield Moor SSSI Water Level Management Plan Final Report [October 2006] ii Water level management objectives There is a single objective for the Hatfield Moor SSSI WLMP: to provide water levels to bring the site into favourable condition (or unfavourable recovering) by 2010. To achieve this objective, a series of specific targets have been identified: • Ensure water levels are appropriate for lowland raised bog habitat • Ensure water levels are appropriate for the lowland ditch system • No increase in flood risk to people or property • Agricultural land adequately drained • Sufficient ditch water levels retained in summer for use by licensed abstractors • Climate change accommodated within water level management • Limit pollution of watercourses from land drainage associated with water level management • High and constant water levels with few fluctuations to preserve buried archaeological assets • No significant adverse effect on cultural heritage resource as a result of implementing the WLMP • No significant adverse effect on Nightjar populations as a result of implementing the WLMP

Proposed actions before the next Water Level Management Plan review This WLMP is designed to be a live document, and as such, it should be subject to periodic review and modification as necessary. It is recommended that this WLMP is reviewed following completion of the hydrological review and feasibility study in June 2007. The following actions should be undertaken before the next Water Level Management Review.

Ref Action Date Responsibility

1 ONGOING MONITORING Yorkshire Water (to October 2006 end of AMP 4) a Continue current surface and groundwater monitoring. onwards Environment Agency Natural England Install self-logging pressure transducers (best location to be b October 2006 Natural England agreed between YWS, EA and EN) c Assess critical interest of Unit 10 (aquatic vegetation) April 2007 Natural England 2 ONGOING CONSULTATION Consultation with landowners regarding management January 2007 Natural England/ a agreements for land adjacent to Hatfield Moor SSSI. onwards Environment Agency October 2006 Natural England/ b Establish Project Board and organise quarterly meetings onwards Environment Agency 3 ADDRESS UNCERTAINTIES THROUGH FURTHER STUDY Continue to analyse groundwater abstraction impacts and a October 2006 Yorkshire Water develop water balance for Hatfield Moor. October 2006 b Hydrological review of Hatfield Moor SSSI. Environment Agency to March 2007 4 FEASIBILITY a Identification of options from results of hydrological review. January 2007 Project Board Feasibility study of options identified during hydrological review January 2007 b and selection of preferred option. Prepare and consult on EIA Environment Agency to June 2007 Scoping Report.

Environment Agency Hatfield Moor SSSI Water Level Management Plan Final Report [October 2006] iii

1 Purpose of the Plan 1.1 Water Level Management Plans A Water Level Management Plan (WLMP) provides a means of balancing and integrating the water level requirements for a range of activities within a Site of Special Scientific Interest (SSSI). These activities include conservation, agriculture and flood risk management.

In particular a WLMP may comprise a written statement that outlines the objectives for a SSSI and how they may be achieved. The plan is endorsed by the operating authority, in the case of Hatfield Moor SSSI, the Environment Agency, Natural England, and as far as possible, by other parties with an interest in the site (see Section 15).

1.2 Water Level Management Plan Review The Government has set a target for DEFRA to “care for our natural heritage, make the countryside attractive and enjoyable for all and preserve biological diversity by…bringing into favourable condition1 [or unfavourable but recovering] by 2010, 95 per cent of all nationally important wildlife sites” [SSSIs].

Natural England is responsible for monitoring the condition of SSSIs, at least once every six years, using a set of common standards. The first assessment of all SSSIs was completed in March 2003. The condition assessment for Hatfield Moor SSSI found that the site is in an unfavourable condition. Half of the site is considered to be either unfavourable declining or unfavourable no change, and without intervention, these areas will become progressively worse. Management measures are in place for the other half of the site which is considered to be unfavourable recovering.

In 2004, Defra and Natural England carried out a review of SSSIs in England, and identified 87 priority sites where water level management was the main reason for an unfavourable condition. Of these, the Environment Agency has the primary responsibility, as the operating authority, for bringing 64 sites back to favourable condition, by achieving appropriate water level management. Hatfield Moor SSSI is identified as a priority site nationally and water level management is essential to delivering favourable condition.

To achieve the Government target outlined above, the Environment Agency, in consultation with Natural England, will review the existing WLMPs for each of the 64 sites identified. A revised WLMP will be produced for each site with an action plan to implement the WLMP, by end of December 2006. By producing and implementing a WLMP, the Environment Agency is fulfilling its statutory duties to nature conservation. The Environment Agency has established a WLMP review process for each of the 64 SSSIs (see Figure 1.1).

1 Favourable condition means the SSSI is being adequately conserved and is meeting its conservation objectives; however, there is scope for enhancement of these sites.

Environment Agency Hatfield Moor SSSI Water Level Management Plan Final Report [October 2006] 1

A site-specific WLMP has never been produced for Hatfield Moor SSSI. This document will bring together studies undertaken over the last six years and will aim to provide a greater understanding of the site’s hydrological regime, looking specifically at changes since peat extraction ceased. The Hatfield Moor SSSI WLMP aims to take into account the aims of all interested parties on or around the site including conservation, agriculture and flood defence.

Figure 1.1 Water Level Management Plan review process

Revised WLMP and 1. Review of existing WLMP

action plan

2. Revised WLMP signed- off and action plan approved

selection of preferred

Only if construction work is required to WLMP review following restore the site option to restore the SSSI 3. Feasibility (appraise options and select Environmental preferred option) Scoping Report

restore the SSSI

4. Detailed design Environmental (submit planning Statement or application, if required) Report WLMP review following construction work to

5. Construction and Environmental implementation Action Plan

Water Level Management Plan deliverables Steps in Water Level Management Plan

Environmental Impact Assessment deliverables

Environment Agency Hatfield Moor SSSI Water Level Management Plan Final Report [October 2006] 2

1.3 Parallel studies There are several studies being undertaken in parallel with this WLMP which need to be considered. Each study is described briefly in Table 1.1 below:

Table 1.1 – Parallel studies

Study Details

Mott MacDonald (2006) is currently undertaking field studies and analyses to demonstrate the significance of groundwater abstraction at Boston Park and Hatfield Woodhouse as part of the Yorkshire Water Services AMP 4 study. Yorkshire Water AMP 4 Earlier work undertaken under AMP3 indicated no impact but this was studies uncertain at Hatfield Moor. The potential impact of abstraction on Hatfield Moor is being investigated further by measurement and developing a water balance during AMP 4. The next major report is expected in early 2007 with completion in 2008. Stage 3 of the Review of Consents stated that all local YWS abstraction should go forward to Stage 4 along with other abstractions which could have Habitats Review of an in-combination impact. The Environment Agency Lower Trent Area Water Consents Resources team will complete Stage 4 by March 2008 to tie-in with the YWS work. The Environment Agency Lower Trent Area Water Resources team are currently preparing the Idle and Torne CAMS. The catchment is considered Idle and Torne to be over-licensed and over-abstracted. The preliminary results will be Catchment Abstraction presented in July 2006 and the CAMS will be completed by end of March Management Strategy 2007 following a sustainability appraisal. The needs of the abstractor (economic well-being of the community) and the environment need to be balanced.

Tidal Trent Strategy The Tidal Trent Strategy is ongoing. There are approximately 250 properties potentially affected by flooding but it is agricultural communities and livelihoods that are at risk. Keadby Pumping Station is at the head of the Isle of Axholme pumped drainage system and pumps water into the Tidal Trent. In the short-term Keadby Pumping Station (next 5 years), the pumping station currently requires work to ensure it Strategic Study remains operational. In the longer-term, the Environment Agency Lower Trent Area Flood Risk Management team will carry out a strategic study to investigate options for the pumping station, and flood risk management and land drainage in the wider catchment. The strategic study is likely to commence in late 2006.

2 Site Details

Site Name Hatfield Moor County South Yorkshire Grid Reference SE 705060 Area 1400.7 ha Site Status SSSI Details of designated interest features are provided in Section 4. The full citation for Hatfield Moor SSSI is provided in Appendix A. Date notified (under 1949 Act) 1954 (last revised 1977) Date notified (under 1981 Act) 1982 (last revised 1988) Operating Authority Environment Agency, Midlands Region, Lower Trent Area Natural England team Humber to Pennines Team Local Planning Authority Doncaster Metropolitan Borough Council Owners/occupiers Natural England holds details of SSSI land ownership

Environment Agency Hatfield Moor SSSI Water Level Management Plan Final Report [October 2006] 3

3 Site Location Hatfield Moor SSSI is located approximately 10km east of Doncaster in the Humberhead Levels. The moor is a remnant of a once extensive lowland raised bog and constitutes the second largest lowland raised peat bog in England. Figure 3.1 shows the location of Hatfield Moor SSSI.

Hatfield Moor SSSI is bounded to the north by the Hatfield Waste Drain, to the east by the North Idle Drain, to the south by the River Torne and to the west by a series of sand and gravel pits, some of which have been restored as surface water lakes. Lindholme Island (which is not part of the SSSI) is a sandy ridge at the centre of the site with a surface elevation slightly higher than the surrounding land (Entec, 2003).

The moors lie within the Isle of Axholme which is an extensive area drained for agriculture via a series of drains and high level carriers. Keadby Pumping Station lies at the head of the system on the River Trent approximately 14km to the north east of Hatfield Moor. Agricultural land forms the dominant land use surrounding the moors as well as former gravel workings on the western edge. There are several settlements including Wroot to the south and Sandtoft to the north east.

Hatfield Chase Ditches SSSI lies to the east of Hatfield Moor and comprises the North Idle Drain, North Level Engine Drain and South Engine Drain, with some of their feeder ditches.

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4 Nature Conservation Interests 4.1 Nature conservation designations The importance of Hatfield Moor is reflected in its nature conservation designations. As well as being a SSSI, parts of Hatfield Moor are also designated as a: • Special Area of Conservation (SAC) under the EC Habitats Directive • Special Protection Area (SPA) under the Birds Directive • National Nature Reserve (NNR)

The boundaries of these conservation designations are shown on Figure 4.1 and a brief description of each is given below. 4.1.1 Hatfield Moor Special Area of Conservation The majority of Hatfield Moor SSSI is designated as a Special Area of Conservation (SAC) for degraded raised bogs still capable of natural regeneration. These are “areas where the hydrology can be repaired and where, with appropriate rehabilitation management, there is a reasonable expectation of re-establishing vegetation with peat-forming capability within 30 years” (European Commission DG Environment 2003). 4.1.2 Thorne and Hatfield Moor Special Protection Area Part of the Hatfield Moor SSSI is designated as a Special Protection Area (SPA) as it is considered an important habitat for supporting Nightjar populations of European importance. Nightjars are listed on Annex I to the Birds Directive. The site forms part of Thorne and Hatfield Moor SPA. Thorne and Hatfield Moor is also an Important Bird Area identified by BirdLife International for its Nightjar populations. 4.1.3 Humberhead Peatlands National Nature Reserve Most of Hatfield Moor SSSI is designated as a National Nature Reserve (NNR). NNRs were established to protect the most important areas of wildlife habitat and geological formations in Britain, and as places for scientific research. They are considered to be among the best examples of a particular habitat. The site forms part of the Humberhead Peatlands NNR. 4.1.4 Non-statutory designations Doncaster Metropolitan Borough Council has designated several sites of local nature conservation importance. These include woodland sites adjacent to Hatfield Moors SSSI.

Draft Habitat Action Plans2 (HAPs) have been prepared by Doncaster MBC as part of the Doncaster Biodiversity Action Plan. This includes a specific HAP for lowland raised mire which outlines proposed objectives including: • To ensure the protection and maintenance of lowland raised mire. • To restore degraded sites and ensure appropriate management of lowland raised mire. • To create water level conditions where lowland raised bog communities can re-establish, by 2010. • To create wetland habitat that could succeed to boggy habitat and create complementary habitat adjacent to bog areas

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4.2 Hatfield Moor SSSI – notified habitats

4.2.1 Broad habitats Hatfield Moor SSSI is split into 24 units, and consists of four broad habitat types: bogs, rivers and streams (lowland ditch system), standing open water and canals, and lowland acid grassland. Figure 4.2 shows the location of units, the broad habitat types and key habitat features within the SSSI.

Natural England’s condition assessment3 provides some useful information on the habitat features present within each unit. Bogs are the dominant broad habitat within the site. There are areas of heathland and birch woodland in drier areas around the edge of the site and in the centre surrounding Lindholme Island. These areas are likely to be important for Nightjar and are included within the SPA designation boundary. Unit 10 comprises a lowland ditch system and is not included within the SAC or SPA designations making it unique within the SSSI.

A habitat description and water level requirements, derived from the favourable condition table, for the key water-related broad habitat types are outlined below. These requirements are important as they give an indication of how water levels should be managed on the site to maintain favourable condition. Further hydrological studies will add to the current understanding of water level requirements. 4.2.2 Lowland raised bogs Morgan-Jones et al (2005) provide a comparative description of a natural and a degraded lowland raised bog. Lowland raised bogs are ombrotrophic (rainwater-fed) systems which are usually isolated from the underlying groundwater. This results in acidic conditions with few nutrients supporting distinctive plant communities. Under anaerobic conditions, organic matter decomposes slowly and is preserved as peat. Peat accumulates to form a raised dome (mire expanse) which is bounded by a drier edge (rand) and surrounded by the lagg (diffuse stream) which forms a wet interface between the bog and the surrounding land. The mire expanse is divided into a thin, active, more permeable upper layer (acrotelm) and a thicker, anoxic, less permeable lower layer (catotelm). The lagg usually comprises fen vegetation and collects surface run-off and groundwater flow.

Figure 4.3 – Cross section of an intact lowland raised peat bog (from Morgan-Jones et al 2005)

3 http://www.english-nature.org.uk/special/sssi/reportAction.cfm?report=sdrt13&category=S&reference=1000536 Environment Agency Hatfield Moor SSSI Water Level Management Plan Final Report [October 2006] 8

The structure of a degraded bog is different from a natural bog. The acrotelm has often been removed and degraded bogs typically have a network of drains and ditches within and around the site. As a result of structural change and drainage, the water table is lower and these drier conditions may encourage scrub invasion.

In degraded bogs, under conservation management, one of the key targets is for vegetation to be composed predominantly of species capable of peat formation including bog mosses (Sphagnum spp) and cotton grasses (Eriophorum vaginatum and E. angustifolium).

Figure 4.4 – Cross section of a degraded lowland raised peat bog (from Morgan-Jones et al 2005)

At Hatfield Moor, there are extensive areas of bare peat. Some areas are revegetating following restoration works (Section 6.4.2). There are some areas which have not been cut for peat including an area to the north of Lindholme Island, and in the south west of the site. Unit 4 to the north of Lindholme Island contains some areas of remnant bog vegetation with occasional Erica tetralix (cross-leaved heather) and Eriophorum vaginatum (hare’s tail cotton grass). Similar vegetation is found in units 2 and 12. Where scrub has been cleared, there is more substantial cover of bog vegetation including occasional Sphagnum cuspidatum, S fimbriatum and S fallax, with E vaginatum and Calluna (heather) being more dominant.

The favourable condition table compiled by Natural England for the degraded lowland raised bog habitat type provides an indication of the water level requirements of this habitat4. Other key factors in determining favourable condition include vegetation composition and habitat structure. The favourable condition table is provided in Appendix A.

4 These water level requirements are based upon the best available information from Natural England provided by Common Standards Monitoring Guidance for lowland wetland habitats (JNCC, 2004). Environment Agency Hatfield Moor SSSI Water Level Management Plan Final Report [October 2006] 9

Water level requirements deduced from the favourable condition table for degraded lowland raised bog include:

• Water table close to ground level (within approximately 10cm of the surface) and indicative of anaerobic conditions. A suggested measure is that the mean free groundwater level over the mire expanse should not fall more than 25cm below surface in more than one year in five. However the uneven bog surface should be taken into account when using such a measure.

• The reinstatement of an undrained area around the raised bog to bear fen, wet grassland, wet heath and wet woodland. The extent of such an area should be determined by further hydrological studies. This would provide stable water levels close to ground level around the edges of the raised bog. A suggested measure of this is that water levels in ditches should not fall more than 50cm below ground level in more than one year in five. Also the groundwater underlying the bog should be contiguous with peat aquifer. This can be deduced from a comparison of water level behaviour in piezometers at a range of depths.

4.2.3 Lowland ditch system Unit 10 comprises a lowland ditch system within arable land, with an unusual combination of acid and base rich aquatic plant communities. There is a rich collection of Potamogeton pondweeds, submerged species and diverse emergent and marginal vegetation.

Natural England does not consider that this habitat needs to be restored but that it does need appropriate water level management to maintain its interest. High water levels are important in spring and early summer for semi-aquatic riparian invertebrates. Water quality is also an important issue for this habitat as there should be an acidic influence.

The favourable condition table compiled by Natural England for the lowland ditch system habitat type provides an indication of the water level requirements of this habitat5. Other key factors in determining favourable condition include water quality, habitat structure and species composition. The favourable condition table is provided in Appendix A.

Water level requirements deduced from the favourable condition table for the lowland ditch system include:

• Except for parts of the ditch system that dry up naturally in the summer or are being allowed to succeed to swamp in a long management rotation or are influenced by tidal flow, a good depth of water should be maintained. High water levels are particularly important in spring and early summer for semi-aquatic riparian invertebrates. A suggested measure is a summer water depth of at least 0.5m in minor ditches and 1m in major drains. An appropriate depth to benefit both the degraded lowland raised bog and lowland ditch system habitat types should be determined through further hydrological study.

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4.2.4 Standing open water Standing open water is the dominant broad habitat along the western edge of the site and comprises a series of former gravel workings. Here the peat has been removed completely then sand and gravels extracted. These areas are being restored as lakes and are not expected to be restored to bog habitat. However, they are thought to provide a hydrological buffer and the aim here would be to maintain water levels. The vegetation along this western edge may be suitable for supporting Nightjars. The areas surrounding open water, particularly in units 11 and 23, comprise bare sand, dry acid grassland and unimproved neutral grassland. These areas could be restored to heathland and be important for reptiles. Nightjars tend to be discouraged from these areas because of disturbance, especially horse riding.

4.3 Species of nature conservation importance Hatfield Moor SSSI supports a number of species of nature conservation importance. Species referred to within the SSSI citation and condition assessment are outlined in Table 4.1. This does not provide a comprehensive list and the potential for other protected species should be investigated prior to any construction works required.

Table 4.1 – Species of nature conservation importance

Latin name Common name Level of importance

PLANTS Vaccinium oxycoccus Cranberry County Myrica gale Bog myrtle County Andromeda polifolia Bog rosemary County Potamogeton spp Pondweeds (assemblage) County Callitriche truncate Short-leaved water starwort Nationally rare INVERTEBRATES National Curimopsis nigrita Mire pill beetle Schedule 5 Wildlife and Countryside Act (as amended) Metrioptera brachyptera Bog rush cricket County National Coenonympha tullia Large heath butterfly Schedule 5 Wildlife and Countryside Act (as amended) BIRDS International, Birds Directive Caprimulgus europaeus Nightjar Red list Luscinia megarhynchos Nightingale Amber list Vanellus vanellus Lapwing Amber list REPTILES AND AMPHIBIANS National Vipera berus Adder Schedule 5 Wildlife and Countryside Act (as amended) MAMMALS Lepus europaeus Brown hare National

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A species of particular importance at Hatfield Moor is the Nightjar. Nightjars breed in the UK between late April and September. They need bare ground to nest on and find this on heathland, commons and moors, as well as open woodland. Nightjars are nocturnal birds and can be seen hawking for food at dusk and dawn (RSPB website, 2006).

4.4 Conservation aims

4.4.1 Natural England conservation objectives Natural England has set conservation objectives to restore the site, and particularly the habitats outlined in Section 4.2, to a favourable condition. Favourable condition requires that site specific standards are met for each designated interest feature.

Targets have been set for each habitat on the site, and, the degree to which these targets have been achieved, determines the condition status of the site. A series of targets has been provided by Natural England, in the form of a favourable condition table for water level management features within the SSSI (degraded bog capable of natural regeneration and lowland ditch systems). Attributes include:

• Active peat formation: vegetation composed predominantly of peat forming plants to achieve a net accumulation of peat.

• Water availability to lowland ditch system.

• Water quality of the lowland ditch system.

Natural England’s conservation objectives for the European interests on the SSSI are: • “To restore to favourable condition the area currently notified as degraded raised bog. • To maintain* in favourable condition, the habitats for the populations of Nightjar, with particular reference to degraded bog capable of natural regeneration as a precursor of active raised bog. * maintenance implies restoration if the feature is not currently in favourable condition.”

4.4.2 Humberhead Peatlands NNR site objectives The following site objectives were outlined in the Humberhead Peatlands NNR Management Plan Consultation Document (December 2005). These will be superseded once the main NNR Management Plan is produced. The NNR site objectives will need to be considered when developing options to provide water levels for favourable condition at Hatfield Moor SSSI.

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Table 4.2 – Humberhead Peatlands NNR site objectives

NNR objective Details

• Areas targeted for mire restoration will be retained at optimum water levels, surface milling fields will be kept wet and water loss from these areas will be minimised. This will be achieved primarily by manipulation To restore lowland of water levels. raised mire habitat over • Specific actions include: 1 the greater part of the • installation of dams and sluices NNR • works to reduce seepage • management of areas of trees and shrub • use of supplementary water from elsewhere if required and as appropriate To maintain and • Existing mire habitat will be enhanced by maintaining high and stable develop the full range water levels in mire areas and controlling inappropriate vegetation. 2 of wetland habitats • Marginal screen of appropriate mire edge habitat will be retained and currently present on the developed in suitable locations and other appropriate habitats including NNR wet woodland, heathland and fen. To maintain and • Nightjar habitat will be maintained and developed in drier areas. enhance the population 3 of Nightjar in and around the NNR • Natural England will work with external partners to minimise water loss To develop an active from the peat body and manage discharges from the site. Actions wider area programme include: 4 to support the nature • statutory review of consents conservation objectives • WLMPs of the site • management agreements • promotion of agri-environment schemes • Develop links with adjacent farming and drainage interests. To maintain and • Access and interpretation and education opportunities will be promoted enhance the cultural 5 where this will not be detrimental to the ecological interests of the site. values and uses of the NNR • Management of the site will take account of the need to retain identified archaeological interest features. • Cooperation with neighbours To fulfil all legal • Health and safety obligations 6 obligations • Environmental standards and appropriate assessments to be undertaken as required by the Habitats Regulations.

4.5 Conservation management Natural England is currently undertaking works across a large proportion of the site to bring the degraded raised bog into a favourable condition. These works are outlined in Section 6.4.2. Written plans for conservation management and restoration of Hatfield Moor are being developed by Natural England but were not available during preparation of this WLMP. The site management plan will relate primarily to vegetation management at the site and this WLMP should complement it. Comments made during the last site condition assessment suggest that some scrub clearance has taken place.

Natural England own and manage the majority of Hatfield Moor SSSI although there are several areas in private ownership, both residential and agricultural. Natural England is currently negotiating management agreements with some SSSI landowners. Some adjacent landowners

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have entered into entry level Environmental Stewardship agreements. The Farming and Wildlife Advisory Group advises farmers on Environmental Stewardship.

Internal Drainage Boards (IDBs) have a statutory duty for nature conservation under the Land Drainage Act 1991 (as amended in 1994) and the Wildlife and Countryside Act 1981 (as amended by the Countryside and Rights of Way Act 2000). The Land Drainage Act amendment requires IDBs to further the conservation and enhancement of natural beauty ad the conservation of flora, fauna and geological or physiographical features of special interest, and to have regard to the desirability of protecting and conserving buildings, sites and objects of archaeological, architectural or historic interest. The CROW Act amendment places additional conservation duties on drainage boards in relation to SSSIs.

Hatfield Chase IDB has responsibility for the ditches within Unit 10 of the SSSI although this land is privately owned and in an Environmental Stewardship Scheme. Hatfield Chase IDB is in the process of preparing an environmental policy which looks at sensitive ditch management. Responsibility for the maintenance of other ditches rests with the riparian owner, that is, the landowner adjacent to the ditch.

5 Other Land Use The majority of Hatfield Moor SSSI comprises a barren expanse of former peat milling fields and a network of drainage ditches. Peat extraction within the NNR ceased in 2004. Some limited peat extraction is still occurring near the Scott factory. The site is now undergoing restoration and bare peat areas are beginning to revegetate. There are large areas of mature woodland particularly around the edges of the site and around Lindholme Island.

The Peatlands Way is a long distance trail which runs along the boundary of Hatfield Moor. Thorne and Hatfield Moors have been designated as open access land under the Countryside and Rights of Way Act 2000. An access strategy is currently being developed by Doncaster Metropolitan Borough Council working with the Countryside Agency and Natural England.

Lindholme Island comprises an area which in the past has been used for arable farming. Lindholme Island itself is outside the SSSI boundary. To the north of Lindholme Hall, there is an area of woodland/moorland which lies within the SSSI/SAC and SPA boundary. The landowner in this area is considering using the woodland area for keeping livestock (pigs). Lindholme Island is accessed via Lindholme Bank Road.

Along the western edge of Hatfield Moor, there are recent gravel workings (often worked down into the underlying Sherwood Sandstone) which have now been restored to a series of lakes, some of which are used for recreational fishing. There is no fishing within the SSSI itself. The fishing and recreational lakes are all outside the SSSI although there is potentially some hydrological connection between these lakes and the SSSI (see Section 6.4.3).

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Figure 5.1 – Key land use features within and adjacent to Hatfield Moor SSSI

Scott’s yard

Lindholme Compressor Bank Road station Gas well

Lindholme HM Prison Lindholme Island

Lindholme lakes Tyram Hall pits – now fishing lakes

Domestic property Woodland Agricultural land Wroot village Gravel workings Re-vegetating peat Gas pipeline

Scottish Power operates a natural gas storage facility within a layer of porous sandstone adjacent to Hatfield Moor. Before the gas can be returned to the network it must be returned to the appropriate pressure. There is a well station next to the road near Lindholme Island and a compressor station adjacent to Lindholme Prison. A 12 kilometre pipeline provides the link between the storage facility and Transco's Gas Transmission System. This pipeline runs under Lindholme Bank Road.

The dominant land use type surrounding the moors is agriculture. The Isle of Axholme is a prosperous agricultural area comprising mainly arable cropping. Land to the north, east and south east of Hatfield Moor is classed as grade 2 agricultural land (grade 1 is the best and grade 5 is the poorest quality).

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6 Hydrology

6.1 Background

6.1.1 Introduction to the hydrology of lowland raised bogs Natural lowland raised bogs are rainwater fed and typically independent of the underlying groundwater. Bogs can develop on either relatively impermeable or permeable drift material. In the latter case, peat fibres can block the pore spaces of the underlying drift, thus creating an impermeable layer at the base of the bog. However, such blockage does not always occur and some bogs show hydrological continuity with underlying aquifers. The acrotelm has a much greater capacity for storing rainfall than the catotelm, which is always below the water table, although the storage capacity of the acrotelm depends on time of year.

When peat is cut, the acrotelm is removed. The bare peat surface that remains is typically the humified peat that formed the catotelm. As this peat dries, it can crack, with the cracks acting as drainage channels. Peat bogs are also artificially drained to enable cutting, and a degraded bog would typically have a series of drainage channels cut through its surface.

Under natural conditions, the main loss of water from the system is through evaporation and transpiration where there are vascular plants. However, when bogs are degraded, there is a change in the components of the water balance and losses through surface water drainage and potentially vertical seepage may become important. 6.1.1 Historical development of Hatfield Moor Hatfield Moor is unique as it was not formed on top of fen mire and in places may have been formed straight onto sands and gravels (although the extent to which this happened across the site is unclear). The formation of the moor began in the early Bronze Age (approximately 3500 years BP). This is thought to have been initiated by a change to a wetter climate and changes in the configuration of the Humber estuary (Limbert, 1978). Before water levels rose, the area would have been a heath/woodland habitat. The trees which covered the area at this time began to die and were gradually replaced by Sphagnum mosses, the remains of which accumulated to form peat. This led to the formation of an ombrotrophic raised mire. As evidence of this temporal pattern of formation, fossilised wood has been found at the base of the peat deposit.

Historically Hatfield Moor was surrounded by the Rivers Torne and Don. The former extent of the moors is likely to have been to these rivers. The Torne, although canalised, flows along approximately the same course as it did prior to canalisation. The Don, however, has been diverted. Its former course was where the M180 is now (see Figure 3.1).

Peat has been extracted from Hatfield Moor since the 14th Century. Initially this was small-scale hand cutting to provide fuel. However, in the 1960s, larger scale extraction began to meet horticultural demands for peat. During this process, vegetation was removed, and drains were cut to a 1m depth every 20 metres. These drainage channels then fed into deeper drains to remove water from the site.

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Under the most recent extraction regime, the top 2cm of peat was broken up, left to dry, and then removed. This process is called peat milling. At the site, the majority of the acrotelm has been removed and the bare peat surface that remains is the peat that comprised the catotelm. There has been a 1-2m loss of peat and in some areas the vegetation has been completely stripped. The former catotelm peat has dried out and may take several years to re-wet. Natural England is currently undertaking restoration works. These are outlined in Section 6.7.

6.2 Topography Hatfield is a low-lying area with a surface elevation of around 0.5-2.5 m AOD. Lindholme Island, a sandy ridge, is a notable feature in the centre of the site with an elevation slightly greater than the surrounding moor (Entec, 2003). There is anecdotal evidence that where the peatland surrounding Hatfield Moor has been drained for agriculture, it has undergone shrinkage (Environment Agency Flood Operations, pers comm.).

The topography of Hatfield Moor has been significantly altered by peat extraction although a detailed topographic map of the area is not available (Mott MacDonald, 2006). LiDAR data is available but has not been interpreted in relation to water levels for Hatfield Moor specifically. Interpretation of this data should be undertaken by the Environment Agency so that it can be incorporated into further studies.

6.3 Geology and Soils

6.3.1 Solid geology Hatfield Moor is underlain by Triassic Sherwood Sandstone which dips in the east beneath Triassic Mercia Mudstone. Mercia mudstone underlies only the far south-eastern corner of the SSSI (Mott MacDonald, 2006). 6.3.2 Drift geology The sandstones are overlain by glacial (Devensian) and post-glacial (Holocene) deposits. To the west of Hatfield Moor the surface geology is composed of gravels deposited in a riverine environment during the late Devensian. Deposits beneath the moor consist of a sand bed overlain by laminated silts and clays that were laid down in an ice dammed lake known as Lake Humber. These clays thicken towards the east across the Moor and have a very important role in isolating groundwater in the peats and shallow drift from the underlying sandstone. Along the western edge of the moor, sand and gravel has been extracted and the former gravel pits have been restored or will be restored as lakes.

In the centre of Hatfield Moor, Lindholme Island is composed of a ridge of sand and gravel which was deposited by glacial melt water at the margin of Lake Humber. These low lying lake sediments are overlain by sands that were wind blown from the west during the early Holocene when the landscape resembled that of present day arctic tundra. These deposits outcrop along the west facing slopes of the Isle of Axholme. A core taken from the moor revealed the presence of sand immediately below the peat (Limbert, 1978). This is likely to represent the wind blown sands.

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The upper part of the drift layer is peat. This has a variable thickness depending upon the extent of peat milling works undertaken. On average, over the worked areas, the peat has a depth of 0.5m but the remaining thickness of peat varies between 0 and 2 metres (Entec, 2003). The extent of peat prior to milling is unknown.

The morphology of the peatland has been modified by extensive peat cutting and drainage. The low gradient of the moor means that the watercourses formed by drainage activities (drains) have very little energy and as a result show no evidence of active erosion. In addition, the numerous sluice gates and other structures control the flow in these watercourses, which is often ponded or extremely sluggish and this further reduces the potential for erosion.

Over much of its area, where recent peat cutting has taken place, the peat is vegetation free. There is evidence of standing water on the surface of the peat. This could suggest that drying out in the past has resulted in the peat becoming slightly hydrophobic as often happens once peat dries out (Holden et al, 2004). However, the recent restoration works should enable the peat to wet-up once more, albeit gradually. The bare peat surfaces are also vulnerable to wind erosion, although this does not appear to be causing a significant loss of peat. 6.3.3 Hydrogeology The relative permeability of superficial deposits determines how water moves both laterally and vertically. Superficial deposits provide a critical link in understanding the relationship between shallow groundwater levels in the peat, and the underlying sandstone (and therefore the potential impact of YWS’s public supply abstractions) (Mott MacDonald, 2006). The British Geological Survey (BGS) has recently constructed a 3D model of the superficial deposits and has classified the area into domains based upon the hydrogeological properties of the deposits, in particular their vertical permeability. Data from BGS has been examined by Mott MacDonald as part of the YWS studies (Mott MacDonald, 2006). The data highlights areas where there is likely to be a low permeability layer, restricting vertical flow, and where a hydraulic connection is to be expected. Considerable areas of the Moor are underlain by this low permeability layer and are classed as weakly permeable, with the exception of the western edge and around Lindholme Island, where there are more permeable superficial deposits overlying the Sherwood Sandstone.

This dataset may form an important source of information. However, caution should be applied as the regional scale of this data may not pick up small-scale differences in the superficial deposits which may be important in terms of restoring water levels at the site. It is also unlikely that this data will record whether or not peat fibres have blocked pores in the uppermost layer of any drift. Therefore a permeable layer, may, in practice, be relatively impermeable.

6.4 Current Hydrological Regime

6.4.1 Climate Rainfall and evaporation/transpiration respectively are potentially the largest source and loss of water to Hatfield Moor. The two closest rain gauges to the moors are Crowle Dirtness (SE 749 098) and Lindholme (SE 676 070) although records for these are incomplete to 2006. MORECS average rainfall data is also available for square 100. From the available data sources, Mott

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MacDonald (2006) has deduced that in 2005, annual rainfall within the vicinity of Hatfield Moor was around 500mm or less.

MORECS data indicates that the long term average potential evapotranspiration (PE) is 595mm/year with a PE for 2005 of 695mm. Mott MacDonald (2006) reported Actual Evapotranspiration (AE) from Hatfield Moor for 2005 to be 582mm. Therefore, lower water tables would be expected across the site. This will be investigated further as the water balance is developed.

Hydrologically Effective Rainfall (HER) values vary from around zero (1994-95 and 2004-05) to 257mm (2000-01) with an average of 91.7mm/year (Mott MacDonald, 2006). From initial investigations, Mott MacDonald (2006) has suggested that if Hatfield Moor retained all the effective rainfall in all years, there would still be a need to provide additional water in some years to maintain permanent wetting. Changes in the vegetation resulting from restoration may affect AE. This will be investigated further as the water balance is developed.

Mott MacDonald (2006) has highlighted some issues with climate data. MORECS data is averaged over a 40km square grid and the values generated reflect the dominant land use type, arable land. Hatfield Moor lies on the eastern edge of the MORECS square, in an area of lower rainfall and with an open water/wetland land use type. AE from this land use type may be much higher therefore the AE value given above may be an underestimate. These data issues could be resolved by applying MOSES-PDM data to the site as Hatfield Moor will be the dominant land type within the 5km square. This work is currently being undertaken by Mott MacDonald.

Restoration of a peat bog is a long term process. Therefore, issues such as climate change and sea level rise need to be considered. Climate change is likely to affect the water balance of the site with potentially less rainfall and more evaporation/transpiration as a result of higher temperatures. Sea level rise could be a major issue as the site lies 1 to 2m below sea level. Sea level rise is predicted to be about 6mm/year at present. Saline intrusion could have an adverse effect on plant communities. 6.4.2 Surface water drainage Hatfield Moor lies within the Isle of Axholme pumped drainage system. The drainage system dates back to the 17th century when King Charles commissioned Cornelius Vermuyden to undertake land drainage improvement. These works comprised river diversion, excavation of new drains and construction of floodbanks. There are approximately 120 miles of drains within the system which is designed to prevent flooding in low-lying farmland.

Drainage was initially by gravity; this has since been replaced by pumped drainage via 21 pumping stations. These lift water approximately 2.5m into high level carriers (main rivers) which then transport water to Keadby, North Lincolnshire. There are also a number of smaller field pumps operated by farmers throughout the area.

The Environment Agency operates 12 pumping stations with others operated by Internal Drainage Boards (IDBs). The IDBs have substations within the Environment Agency pumped catchments and pay a contribution to the running costs of the Environment Agency pumping stations. Figure 6.1 shows the locations of pumping stations in the vicinity of Hatfield Moor.

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Environment Agency pumping operations Keadby Pumping Station lies at the head of the system and determines the water levels in the main river system. There are low gradients within the area, for example, the gradient from Keadby to Candy Farm pumping station is approximately 1 in 13,000. Therefore any change at Keadby will have a significant effect in the rest of the system. Due to the low gradients and few physical barriers, all pumping stations discharging into the system operate at similar levels.

There is a system in place at Keadby, which takes readings from Candy Farm Pumping Station. When levels reach 0.6m AOD at Candy Farm, this is a trigger to start gravity run off or pumping.

Within the pumped drainage system, summer water levels are maintained approximately 300mm higher than winter levels but still allow enough drain capacity during heavy rainfall periods. Water is let back from the Environment Agency high level carriers to the IDB’s drain network in the summer months so that farmers can pump out water to irrigate their crops. When the falling level at Keadby Pumping Station forebay (see Figure 3.1) reaches 0.4m AOD, let back stops and farmers are notified to stop irrigation of their crops. This is written into licence agreements where possible, but some farmers have a licence of right, and under present legislation this cannot be stopped.

Historically, the switch from summer to winter levels was made in November. Summer levels were then resumed in June. However, now summer levels are often maintained throughout the winter due to drier conditions. This has been the case for approximately 4-5 years (Environment Agency Flood Operations pers comm.).

The Environment Agency has a mass balance model that evaluated the pumping volumes. Between June and August the pumps are run infrequently but in winter the pumps are run for about 3-4 hours a day during wet periods. The pumping stations are never fully switched off; one duty pump is always on. This is to avoid a flood event following heavy rainfall during the night or weekend.

Internal Drainage Board pumping operations Hatfield Chase IDB is responsible for maintaining water levels for agriculture. This is carried out on a needs basis. However, the IDB’s remit is gradually changing to a consideration of the wider environment and agriculture. For example, near Boston Park, Hatfield Chase IDB is trying to maintain ditches for biodiversity as well as water levels.

The IDB’s drainage system has been automated for 30 years with telemetry installed 12-15 months ago. The IDB provides the Environment Agency with pump data. Unlike the Environment Agency pumping stations, IDB structures cannot let water back into the system.

There have been no recent changes in operations. Recent increases in pumping to the north of Hatfield Moor have been attributed to rising groundwater since Yorkshire Water turned off their public water supply abstraction at Hatfield Woodhouse due to pollution (Hatfield Chase IDB pers comm.). However, there may also be a longer-term trend in rising groundwater (Yorkshire Water pers comm.).

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Flooding within the Isle of Axholme Without the Trent’s major flood banks and the pumping system, the Isle of Axholme would flood twice a day. The River Trent has 1 in 100 year defences. The last major breach was in 1947 but during the 2000 floods about 40-50 properties were flooded in the lower Trent north area, mainly on the Trent banks. The Tidal Trent Strategy is currently being prepared (see Section 1.3).

A 24 hour alarm system is operated from Sapphire House (Solihull) for the most important pumping stations. There are plans, using the Environment Agency’s emergency workforce, for dealing with flooding incidents. This is controlled by the Environment Agency’s flood operations department. Flood risk and other departments also contribute to dealing with outside enquiries, public bodies, IDBs, and flood forecasting.

At present there are no problems with property flooding within the Isle of Axholme, as the system is currently managed. There have been no recent flood incidents to crops. Hatfield Chase IDB reported that some localised flooding occurred in summer 2000 as a result of heavy rainfall overnight while the pump was on a high summer level.

Surface water movements on Hatfield Moor Surface water leaves Hatfield Moor via drains which are then pumped into the high level carriers (see Figure 6.1). This occurs in three main locations: • In the north to Hatfield Waste Drain via Goodcop pumping station; • In the south east to the River Torne via Porters Drain then the East Ring Drain and Tunnel Pits pumping station; • In the south to the River Torne via Candy Farm pumping station.

Surface water levels in the ditches surrounding Hatfield Moor are influenced by pumping. There are significantly higher water levels in summer compared with winter as levels are kept high in summer for irrigation and to maintain high shallow groundwater level to allow crops to uptake moisture from soil (Mott MacDonald, 2006).

As part of its restoration works, Natural England has installed peat bunds and several sheet pile dams (with penstocks) at the site. The primary objective of these works is to hold water levels at or around the surface level. This will allow cotton grasses to establish which provide a framework that Sphagnum spp can begin to grow on. Cotton grasses also create a more humid microclimate in the 10cm above the mire surface so that the bog mosses are less likely to desiccate. Sphagnum cuspidatum is a pioneer species which has started to spread in the restoration areas.

The approach taken to restoration involves creating cells using peat bunds (see Figure 6.1). These bunds are not completely water tight and plastic membranes have been used in some areas to ensure they are more water-tight. Each cell has a set water level and a water control pipe. The maximum water depth of each cell is 20cm over the ground level of the cell. Above this level, the vegetation would be inundated. The water control pipe therefore transfers water above this level to the drains. The bunding work should be completed by September 2006.

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Natural England has also installed several sheet pile dams (with penstocks) at the site. These have been installed at key locations, at the western, eastern and northern boundaries of the site (where surface water leaves the site towards the high level carriers). These structures are shown on Figure 6.1.

There are some uncertainties concerning the hydrological effect of the restoration works on land adjacent to the SSSI boundary. Further investigation is required to address these uncertainties (see Section 6.4.10). 6.4.3 Open water At the western boundary of the site, there are several lakes which have been created from former gravel pits (see Figure 5.1). It is anticipated that for some of these lakes the bed reaches the underlying sandstone, and could have an interaction with the groundwater.

These lakes are currently disconnected from the surface water drains on Hatfield Moor (Natural England, pers. comm.). However, these lakes are thought to provide a hydrological buffering effect to Hatfield Moor, that is, they reduce the amount of water lost via shallow subsurface seepage to the west of the site. There is a possibility that the drainage system could be re- designed to enable the use of these lakes for storage. As well as providing surface water storage during high rainfall events, using these lakes for storage could also potentially increase the buffering effect they provide. 6.4.4 Groundwater Mott MacDonald (2006) has looked at groundwater data for Hatfield Moor. From a preliminary analysis, it has been observed that groundwater levels measured in the Natural England dipwells (that is, in the peat) are up to two metres higher than those recorded in the shallow drift deposits and the underlying Sherwood Sandstone. Seasonal trends in groundwater levels are apparent with a fall between March and October then a rise between November and March. Observed smaller-scale fluctuations are possibly due to the influence of recharge events although this cannot be confirmed (Mott MacDonald, 2006).

The Sherwood Sandstone forms an important regional aquifer. YWS abstract from the Sherwood Sandstone aquifer at Boston Park (to the south west of the SSSI) and Hatfield Woodhouse (to the north west), accounting for 42.46% of the total licensed amount (Environment Agency, 2006). Both abstractions are currently switched off (Hatfield Woodhouse since December 2002, and Boston Park since 18 December 2005 (although it has occasionally been used (YWS pers comm.) and groundwater levels are starting to recover. YWS is monitoring the change in water levels to investigate the significance of the YWS abstractions on the European designated degraded raised bog habitat (Mott MacDonald, 2006).

There are also several abstractions for agricultural and industrial purposes. The Environment Agency is currently reviewing all consents as required by the EC Habitats Directive. Neither the YWS abstraction licences nor private consents can be shown to have no adverse effect on the site integrity of the SAC (Environment Agency, 2006).

Environment Agency Hatfield Moor SSSI Water Level Management Plan Final Report [October 2006] 23 6 x uey

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6.4.5 Conceptual model A conceptual model represents a picture of a site that has been built up from existing information. Figure 6.2 shows the current conceptualisation of the hydrological system at Hatfield Moor based upon the information outlined above. There are several uncertainties which require further study. These are outlined in Table 6.1.

Mott MacDonald (2006) is currently developing a water balance for Hatfield Moor as part of the YWS AMP 4 studies. This water balance is in its early stages and will be developed further as more data is collected and analysed. The Environment Agency should continue to collaborate with Mott MacDonald to develop this water balance using data obtained through monitoring. Appendix B outlines the current monitoring data available.

Figure 6.2 – Conceptualisation of hydrology at Hatfield Moor

Rainfall SSSI

SSSI 5 Peat bunds Agricultural land

Drainage 2 ditch (some blocked) Evaporation ET Interception Farm Evaporation 3 drain

Peat Lake 1 Drift Perimeter drain W 4 E

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Table 6.1 – Uncertainties and suggested further study

Uncertainty Suggested further study

What is the hydraulic connection • Collaboration with Yorkshire Water AMP 4 studies. between the a) drift and 1 sandstone, and b) peat and drift? How do these vary across the site and surrounding land? What are the losses due to • Actual evaporation/transpiration estimates could be obtained from evaporation/ transpiration continuous dipwell data when the water table is close to the compared with vertical or ground surface. horizontal seepage? How do these 2 • Losses due to horizontal or vertical seepage (depending on vary across the site and location within the site) can be investigated by looking at dipwell surrounding land? data from a dry, cool winter period of several days. If there are losses, these can be attributed to seepage as evaporation/transpiration losses should be virtually zero.

Environment Agency Hatfield Moor SSSI Water Level Management Plan Final Report [October 2006] 25

Uncertainty Suggested further study

Does holding back water on • Review of impacts of current restoration works on surrounding Hatfield Moor deprive surrounding land. areas of water for irrigation or will • Simple modelling work could be undertaken to compare surface restoration of Hatfield Moor result 3 water drainage in peat extraction situation and restoration in increased surface water runoff situation. and/or lateral seepage to • Current Environment Agency and Internal Drainage Board surrounding land (and therefore pumping operations should be reviewed. flooding and/or waterlogging)? Are the lakes at the western edge • Collaboration with Yorkshire Water AMP 4 studies. of Hatfield Moor connected to the • Use modelling work above to test options for surface water underlying sandstone and do they 4 storage. provide a buffering effect? Could these lakes be used for surface water storage? What is the impact of climate • The Environment Agency’s statistical downscaling of the effects of change on rainfall and climate change on weather could be used. The downscaling tools evaporation/transpiration and how use regional-scale outputs from Global Circulation Models and 5 could this affect how much water predict climate changes at the site scale. However, the relative is available to Hatfield Moor? degree of uncertainty with climate change modelling should be considered.

6.5 Current Site Conditions

The condition of Hatfield Moor SSSI was assessed in July 2004. Half of the site is considered to be either unfavourable declining or unfavourable no change, and without intervention, these areas will become progressively worse. Management measures are in place for the other half of the site which is considered to be unfavourable recovering.

Figure 6.3 shows the SSSI units which are unfavourable recovering, unfavourable no change and unfavourable declining. The main reasons given for unfavourable condition are peat extraction, drainage and inappropriate scrub control. Table 6.2 provides a summary of comments made during Natural England’s most recent condition assessment.6

Table 6.2 – Summary of comments made during the last condition assessment for Hatfield Moor SSSI (compiled 1 April 2006)

Broad Unit Condition assessment comments habitat

• Some areas suitable for restoration of bog vegetation. • Eastern side of unit has water levels close to ground surface and some species 1 Bogs such as Eriophorum vaginatum already present. • No active restoration management being carried out. • Northern end of unit very wet with standing water and offers good opportunities for development of peat forming vegetation. 2 Bogs • Unit has potential to support heath and bog vegetation and there is an overlap with conservation of Nightjar. • Unit in active management and positive changes are apparent. • Extensive stands of E vaginatum are present within the unit. 3 Bogs • Unit in active management. Bunds have been installed around part of unit boundary and within unit.

6http://www.english-nature.org.uk/special/sssi/reportAction.cfm?report=sdrt13&category=S&reference=1000536 Environment Agency Hatfield Moor SSSI Water Level Management Plan Final Report [October 2006] 26

Broad Unit Condition assessment comments habitat

• Majority of unit is quite dry and supports open birch woodland although there are 4 Bogs some open areas with favourable (peat forming) vegetation. • Some small scale management but needs to be developed. • Some areas with frequent standing water and saturation of ground surface 5 Bogs suggesting good potential for restoration to bog conditions. • Unit in active management. • Little vegetation within the unit. 6 Bogs • Extensive sheets of standing water, particularly in northern part of unit. • Peat extraction has now stopped in this unit and peat bunds have been installed. • More standing water than in 2003. 7 Bogs • Peat extraction has now stopped in this unit and peat bunds have been installed. • Area of vegetated ground remains in south east section of site. Ditches show 8 Bogs good potential for restoration with some already supporting E vaginatum. • Peat extraction has now stopped in this unit and peat bunds have been installed. • Some scrub control but regrowth, particularly Scot’s pine and birch. • Some areas with good potential for restoration to heathland habitat. 9 Bogs • Bog rosemary occurs in a number of locations. • Unit in active management. • Dredgings from ditches in north fields left on site covering vegetation close to Rivers and ditches. 10 streams • Aquatic vegetation is critical interest in this unit. This was not assessed during the last condition assessment. • Water body surroundings comprise bare ground, dry acid grassland and unimproved neutral grassland. Standing 11 • Drier areas of the unit show good potential for heathland development. open water • No peat forming vegetation within the unit although in the southern end of the unit, Juncus spp beds have formed on a thin layer of peaty soil. • Species poor birch woodlands and bracken beds dominate in the unit. 12 Bogs • Some birch scrub clearance in southern part of unit. These areas support E vaginatum, Erica tetralix and Calluna. • Unit in active management and initial restoration work carried out. Bunds have 13 Bogs been installed around part of unit boundary and within unit. • Management in this unit is considered to be unsuitable. 14 Bogs • If progressed, adjacent quarrying proposals at Dale Pit Quarry may offer an opportunity to bring unit into management. • Crassula (Australian swamp stonecrop) invasion is likely to result in poorer Standing habitat in this unit although the impact is uncertain. Crassula appear to have 15 open water been treated with chemicals. • No peat forming vegetation within the unit. • Good potential for development of peat forming vegetation in centre of unit as shallow pools exist and cotton grasses are well-established. 16 Bogs • Inappropriate management in some areas of the site and some tipping of garden waste. • Active restoration work is needed in this area. • Scotts’ yard was still in use during the condition assessment. 17 Bogs • A small area at the southern end of the unit has good potential for restoration to open heathland.

Environment Agency Hatfield Moor SSSI Water Level Management Plan Final Report [October 2006] 27

Broad Unit Condition assessment comments habitat

• Unit very dry and mostly covered in birch wood and bracken stands. • Ditches generally dry and overgrown except where piling has been installed 18 Bogs along boundary with unit 15. • Area will be managed for Nightjar as too raised to re-wet easily. Lowland • Open grassy field adjacent to Lindholme Hall. 19 acid • No noticeable change since 2003. grassland • Shallow standing water frequent across unit but vegetation remains sparse. 20 Bogs • Unit to be brought into favourable management. • Cover of E vaginatum and Sphagnum in some areas with Calluna dominant in 21 Bogs drier areas. • Restoration work to be undertaken in this unit. • Most of unit dominated by birch and bracken. 22 Bogs • No noticeable change from 2003. • Acid grassland has started to develop on southern part of unit. There is good Standing 23 potential for heathland to develop. open water • No peat forming vegetation in this unit. • Ditches are dry in northern part of unit. • Southern part of site comprises neutral grassland fields. 24 Bogs • Water abstraction may be affecting this unit. May be a good starting point for potential wet grassland/lagg fen.

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7 Water Quality The General Quality Assessment scheme (GQA) is the Environment Agency’s national method for classifying water quality in rivers and canals. GQA scores range from A (high quality) to F (poor quality) and are based on water chemistry, biology, nutrients and aesthetics. Data indicates that water quality within the study area is fair.

Main river water quality within the study area is fair. The water quality of Hatfield Waste Drain is measured between the Sewage Treatment works (SE 685 082) and Goodcop Farm (SE 735 083). In the period 2002 to 2004, the chemical quality in this stretch was Grade D and the biological quality was Grade C. Nitrate and phosphate levels were high. To measure chemical quality, water samples are analysed for ammonia, biochemical oxygen demand (BOD) and dissolved oxygen, and the results are compared with limits to give a grade. It is the lowest grade of these parameters which determines the overall grade. In the Hatfield Waste Drain, BOD was grade B, ammonia was C and dissolved oxygen was D.

Surface water which drains within the Isle of Axholme has a water quality characteristic of the peat deposits which occur within sites such as Thorne and Hatfield Moors and which underlie much of the fertile agricultural land. The acidic conditions within the peat may lower the pH of water and subsequently mobilise metals.

8 Cultural Heritage Hatfield Moor is an area of national importance for archaeology. Appendix C outlines a review of existing cultural heritage information and provides recommendations for an Archaeological Management Plan to be prepared for Hatfield Moor similar to that prepared for Thorne Moor. This plan would inform the WLMP and future management of the site.

A total of sixteen sites of cultural heritage interest have been identified within the study area. The number and importance of known sites within the study area is comparatively low with a total of 16 sites identified from a preliminary search. However, this is more a reflection of the lack of visibility of these sites than their absence. The cultural heritage importance of Hatfield Moor is therefore largely based on its potential.

Important archaeological sites can occur at any level with the peat deposits, or on the pre-peat ground surface. The whole of the study area, including areas previously milled, should therefore be considered to have a high potential for the presence of unknown archaeological deposits. This potential is reduced in areas where the peat and the underlying mineral land surface have been completely removed, such as in areas of modern development and in the quarries on the western edge of the study area. In areas of limited disturbance such as the vegetated peatland to the north of Lindholme Island, there could be palaeoenvironmental deposits of national importance.

Appropriate water level management will be beneficial for the preservation of the cultural heritage resource within the study area. However, construction works to enable restoration could potentially have an adverse impact on the resource. Given the importance and sensitivity of the study area, detailed consultations should be undertaken with South Yorkshire Archaeological Service and the English Heritage Regional Scientific Advisor in advance of any works.

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9 Water Level Management Objectives There is a single objective for the Hatfield Moor SSSI WLMP: to provide water levels to bring the site into favourable condition (or unfavourable recovering) by 2010. To achieve this objective, a series of specific targets are outlined below.

The distribution and general water level requirements of the designated interest features were outlined in Section 4.2. The desired distribution of designated habitats and their water level requirements will determine the targets for water level management for Hatfield Moor SSSI.

From the review of existing information to date, key targets have been identified for Hatfield Moor SSSI in order to achieve the overall objective. Key targets and actions for water level management are outlined in Table 9.1.

Table 9.1 – Key targets and actions for water level management

Target Action Responsibility

1 CONSERVATION – bog habitat Water table close to ground level (within • Undertake hydrological review of a approximately 10cm of the surface) and Hatfield Moor SSSI and collaborate indicative of anaerobic conditions. with Yorkshire Water Service AMP 4 studies to provide greater Environment The reinstatement of an undrained area understanding of the hydrological Agency b around the raised bog to bear fen, wet regime and assess options to grassland, wet heath and wet woodland. provide the water levels required for favourable condition. 2 CONSERVATION – lowland ditch system A good depth of water should be Monitor water levels at regular • Hatfield Chase maintained. A suggested measure is a a intervals by installing depth gauges IDB/Natural summer water depth of at least 0.5m in at strategic points. England minor ditches and 1m in major drains. 3 FLOOD DEFENCE No increase in flood risk to people or • Undertake flood risk assessment as Environment a property. part of an EIA. Agency 4 AGRICULTURAL LAND DRAINAGE • Undertake review of the current Environment pumped drainage operating regime Agency/ a Agricultural land adequately drained. to assess its capacity to Hatfield Chase accommodate increased surface IDB water runoff. 5 WATER RESOURCES • Use existing abstraction model of Sufficient ditch water levels retained in pumped drainage system to ensure Environment a summer for use by licensed abstractors. sufficient water is retained in the Agency ditches. 6 CLIMATE CHANGE Climate change accommodated within • Investigate impact of climate change Environment a water level management. on Hatfield Moor. Agency 7 WATER QUALITY Investigate water quality as part of Environment Limit pollution of watercourses from land • options development. Agency/ a drainage associated with water level Hatfield Chase management. IDB

Environment Agency Hatfield Moor SSSI Water Level Management Plan Final Report [October 2006] 31

Target Action Responsibility

8 ARCHAEOLOGY High and constant water levels with few • Prepare Archaeological Natural a fluctuations to preserve buried Management Plan to inform England archaeological assets. hydrological review and WLMP. • Undertake assessment of any No significant adverse effect on cultural construction works and changes in Environment b heritage resource as a result of water levels on the site’s Agency implementing the WLMP. archaeological resource as part of an EIA. 9 NIGHTJAR • Undertake assessment of any Natural No significant adverse effect on Nightjar construction works and changes in England/ a populations as a result of implementing water levels on Nightjar habitat as Environment the WLMP. part of an EIA and Appropriate Agency Assessment.

10 Constraints and impacts on adjacent ground There are potentially several practical, financial and environmental constraints to implementing this WLMP. The constraints and opportunities identified below should be addressed within a feasibility study and Environmental Impact Assessment (EIA) as part of the implementation of this WLMP.

10.1 Practical and financial constraints

10.1.1 Technical and economic feasibility There is an overall constraint as to what is physically possible at the site from an engineering point of view. A feasibility study should be undertaken to assess the technical and economic feasibility of options considering the following issues:- • A sound understanding of the hydrological regime of the SSSI and surrounding land is essential to ensuring that a robust and sustainable solution is developed. • The amount of water available to the SSSI is affected by climate. There is a risk that intervention to raise water levels may be undermined by climate change impacts such as low rainfall and sea level rise. • There is a risk that by increasing water levels within the SSSI by holding back water, there could be an increased risk of flooding to land and property on Lindholme Island and land adjacent to the SSSI boundary. Ensuring that there is no increase to flood risk to property may present a practical constraint. • The level of maintenance required once a solution is in place may be a practical and financial constraint. A solution requiring least maintenance would be desirable. • Services crossing the study area, particularly the gas pipeline and well compound, could restrict the nature and location of any construction works required. Prior to any works, information should be collected to determine the location of these services.

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10.1.2 Obtaining planning and other consents Potential consent requirements are outlined below:- • Planning consent from the Local Planning Authority (Doncaster Metropolitan Borough Council) may be required for some of the works. An Environmental Statement may be required under the Town and Country Planning (Environmental Impact Assessment) Regulations. An EIA Screening Opinion will be sought from Doncaster Metropolitan Borough Council once a preferred option is selected. • Work proposed in, over, under or adjacent to “Main River” requires the consent of the Environment Agency. An Environmental Statement may be required under the Land Drainage (Environmental Impact Assessment) Regulations. • Under the Land Drainage Act 1991 Section 23, works which affect a watercourse within the Internal Drainage Board District will require consent. • Under the Water Resources Act 1991, an abstraction licence is required from the Environment Agency, by anyone who wishes to take water from a surface or underground source. A licence is not required if the abstraction is for conservation purposes and is required by the statutory conservation body (Natural England) as part of the site management. • Under the Water Resources Act 1991, an impounding licence is required from the Environment Agency for the impounding of any watercourse, ditch or stream, for example by dam or weir. A licence is not required if the impoundment is for conservation purposes and is required by the statutory conservation body (Natural England) as part of the site management. • Natural England assent is required for “operations likely to damage the special interest” (see Appendix A). 10.1.3 Requirement for Appropriate Assessment Natural England has indicated that an Appropriate Assessment is required under the Habitats Directive. This will be an ongoing process throughout the implementation of the WLMP.

10.2 Environmental constraints and opportunities An EIA is likely to be required to determine the environmental acceptability of proposed options to provide the water levels required for favourable condition. The existing environment has been reviewed briefly during preparation of this WLMP. The study area is considered to present the following potential environmental constraints and opportunities for implementing the WLMP.

ENVIRONMENTAL OPPORTUNITIES • Create or restore habitats adjacent to Hatfield Moor SSSI for wider biodiversity gains potentially through the use of Environmental Stewardship Schemes. • Promote Hatfield Moor as a recreational or environmental education resource in the local area. • Protect buried archaeological assets and palaeo-environmental record through raised water levels.

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ENVIRONMENTAL CONSTRAINTS • There is an obvious risk of damaging the habitat for which Hatfield Moor SSSI is designated. Some damage to habitats is expected during construction works and Natural England will need to consider which areas should not be disturbed. • There are some areas of woodland within and adjacent to the site which may be of local nature conservation importance. These habitats may also be important for breeding birds, in particular, Nightjar, and may be of local landscape importance. Consideration should be given to these areas when assessing options to provide water levels for favourable condition. • There are potentially a number of protected species such as reptiles within the study area. Protected species habitat should not be disturbed or damaged during construction works and consideration should be given to potential habitat loss as a result of changes in water levels. • The Hatfield Chase Ditches SSSI lies to the east of Hatfield Moor SSSI. A WLMP is also being prepared for this site. The Hatfield Moor WLMP should not be in conflict with this and likewise, the Hatfield Chase Ditches SSSI WLMP should not conflict with this WLMP. • Although, high stable water levels at the site will be beneficial for the cultural heritage resource, there is a risk that any construction works required may have an adverse effect. • There is a risk of increased flooding or waterlogging in surrounding agricultural land. This could affect agricultural land use adjacent to the SSSI.

A suitable mitigation strategy would be devised in response to any significant environmental effects resulting from the preferred option. As part of the EIA, an Environmental Action Plan (EAP) will be prepared which will include a series of specific mitigation measures for the construction and implementation stage. The EAP will identify specific environmental objectives, targets and actions against which the success of the project can be measured.

11 Alteration to Infrastructure & Procedures No alterations to infrastructure or procedures are proposed for Hatfield Moor SSSI at this point in time. Several options should be considered as part of a feasibility study to achieve the overall objective and series of targets outlined in Section 9. The preferred option may be a combination of these options. Table 11.1 outlines a series of potential options. These are preliminary options for consideration and will be expanded upon as the project progresses to the feasibility stage.

Table 11.1 – Potential options for water level management at Hatfield Moor SSSI

Option Purpose Description

Store water within Retain rainfall on the site and Sub-options could include: SSSI boundary prevent lateral seepage into • Sheet pile around whole site to prevent surrounding land. lateral seepage into surrounding land. • Sheet pile selected areas around the site to prevent lateral seepage into surrounding land. • Create hydraulic mound to prevent seepage Alter pumping Remove excess surface water • Alter pumping operations to allow more operations run off from site during high water to be removed from the site during rainfall events to prevent high rainfall events and for water to be let flooding of surrounding land. back into the site during drier periods. Let back water from drainage • This could lead to water quality problems on system during drier periods. the site which would require further investigation as part of the feasibility study.

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Option Purpose Description

Storage of water Remove excess surface water • Increase capacity of drains surrounding outside of SSSI from site during high rainfall Hatfield Moor. boundary events and store for use in drier • Lakes to west or as wetlands adjacent to months. site. • This could lead to water quality problems on the site which would require further investigation as part of the feasibility study. Wetland creation Create a buffer zone between • Create wetlands/washlands in land Hatfield Moor and surrounding surrounding the peat bog habitat to store agricultural land to minimise surface water runoff and lateral groundwater flooding and water logging in the losses from the site. surrounding land.

12 Other Proposed Action Further study is recommended to address the uncertainties outlined in Table 6.1. It is recommended that this is undertaken as one hydrological review study which incorporates consideration of climate change followed by a feasibility study. The principal aim of the study would be to attain a comprehensive overview of the (hydrological) operation of the Hatfield Moor site, focusing on the interaction of surface water and groundwater, existing storage and hydraulic operations on the site. Additionally, the study would identify potential issues with the site in connection with the (proposed) restoration work, and mitigating measures to tackle these issues. The main objectives would be:

• To identify conflicts between drainage system capacity (on and) around the Hatfield Moor site and the needs of various users;

• To identify alternative solutions that could subsequently be costed and subjected to cost/benefit analyses;

• To identify areas of land most suitable for wetland creation.

The hydrological review will take account of the Yorkshire Water AMP 4 studies being undertaken by Mott MacDonald and recent work undertaken as part of a University of Birmingham MSc Project on soil moisture and shallow groundwater conditions within Hatfield Moor. One of the main aims of this project is to assess the impact of groundwater level changes in the Sherwood Sandstone aquifer on water table and soil moisture conditions within the peat deposits of Hatfield Moor.

Following this, the WLMP review process shown in Figure 1.1 should be followed with the steps including feasibility/outline design, detailed design, and construction and implementation. An EIA would be undertaken to ensure that the preferred option is environmentally acceptable. Table 12.1 suggests a programme of actions required to achieve favourable condition by 2010. This programme runs from October 2006 to March 2010.

Environment Agency Hatfield Moor SSSI Water Level Management Plan Final Report [October 2006] 35

Table 12.1 – Programme of actions required

Ref Action Date Responsibility

1 ONGOING MONITORING Yorkshire Water (to October 2006 end of AMP 4) a Continue current surface and groundwater monitoring. onwards Environment Agency Natural England Install self-logging pressure transducers (best location b October 2006 Natural England to be agreed between YWS, EA and EN) c Assess critical interest of Unit 10 (aquatic vegetation) April 2007 Natural England 2 ONGOING CONSULTATION Consultation with landowners regarding management January 2007 Natural England/ a agreements for land adjacent to Hatfield Moor SSSI. onwards Environment Agency Establish Project Board and organise quarterly October 2006 Natural England/ b meetings onwards Environment Agency 3 ADDRESS UNCERTAINTIES THROUGH FURTHER STUDY Continue to analyse groundwater abstraction October 2006 a impacts and develop water balance for Hatfield onwards (to end Yorkshire Water Moor. of AMP 4) October 2006 to b Hydrological review of Hatfield Moor SSSI. Environment Agency March 2007 4 FEASIBILITY Identification of options from results of hydrological a January 2007 Project Board review. Feasibility study of options and selection of preferred January 2007 to b Environment Agency option. Prepare and consult on EIA Scoping Report. June 2007 5 DETAILED DESIGN AND PLANNING Design preferred option and undertake Environmental June 2007 – a Environment Agency Impact Assessment December 2007 Submit planning and consent applications with b December 2007 Environment Agency Environmental Statement or Report Obtain planning and other consent(s) (assumes c April 2008 Environment Agency maximum 16 weeks determination period) 6 CONSTRUCTION AND IMPLEMENTATION May 2008 a Start construction Environment Agency onwards

13 Contingency Measures A contingency is an unforeseen event, such as a severe flood or drought, or a change in land ownership or land use surrounding the SSSI. Such events may affect implementation of the WLMP. These risks need to be identified, and control measures put in place should these events occur. Contingency measures should be identified following the hydrological review. These will be identified in the next review of the WLMP and should be reviewed periodically.

To reduce risk throughout the life of the WLMP, liaison should be maintained with Natural England, Hatfield Chase Internal Drainage Board, Yorkshire Water and other stakeholders as appropriate.

Environment Agency Hatfield Moor SSSI Water Level Management Plan Final Report [October 2006] 36

Landowners have been consulted during the preparation of this WLMP, however, further liaison will be required throughout the life of the WLMP, particularly in relation to establishing management agreements and the use of Environmental Stewardship Schemes on land adjacent to the SSSI.

14 Unresolved Issues This section outlines issues that cannot be resolved under this plan. These could include either external plans which could affect the water level management of Hatfield Moor SSSI, or risks to implementing the plan such as availability of funding. Unresolved issues are as follows: • A strategic study has been commissioned to consider options for the future of Keadby Pumping Station. One of these options is to cease operations at Keadby Pumping Station and revert to a gravity drainage system. This issue cannot be resolved under this WLMP but liaison should be maintained internally within the Environment Agency over the future of the Isle of Axholme pumped drainage system. • There is a proposal for a new sand and gravel quarry at Dale Pit on the north western edge of the SSSI. A planning application may be submitted within the next six months (Natural England, pers comm.) and will have to measures to prevent water loss from the moor. The application will also have to undergo an Appropriate Assessment under the Habitats Directive, by the Borough Council. The implications of water level management will be considered in his assessment of the application, although previous mitigation proposals, for example a recharge trench, have been criticised as being unlikely to achieve this. This has been raised as an issue in the Review of Consents as a factor that may act in-combination with the groundwater abstractions. It will be further considered in the Stage 4 assessments. This issue cannot be resolved under this WLMP but liaison should be maintained with Doncaster MBC regarding the planning permission. • Following the recent Defra budget cuts, there is a risk that sufficient funding to restore this site to a favourable condition may be unavailable. This may affect both Natural England’s budget for site management and the Environment Agency’s budget for the water level management actions identified in this document. This issue cannot be resolved under this WLMP but liaison should be maintained between Natural England and the Environment Agency.

15 Other Matters This WLMP is designed to be a live document, and as such, it will be subject to periodic review and modification as necessary. It is recommended that this WLMP is reviewed following completion of the hydrological review and feasibility study in June 2007.

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16 Consultees 16.1 Water level management plan consultation Consultation has been undertaken with internal Environment Agency specialists and external consultees. We have compiled a Communication Plan that details the organisations we have contacted and key requirements for consultation throughout the WLMP review process. Table 16.1 outlines the organisations listed within the Communication Plan.

Table 16.1 – Consultees

EXTERNAL ORGANISATIONS Ashfields and West Moor IDB English Heritage North Lincolnshire Council Barnsley and District Epworth Town Council RSPB Amalgamated Anglers' Society Farming and Wildlife Advisory South Yorkshire Archaeology Belton Parish Council Group Service Thorne and Hatfield Moor Blaxton Parish Council Hatfield Town Council Conservation Forum Cantley with Branton Parish Hatfield Chase IDB Thorne-Moorends Town Council Council Country Land and Business Isle of Axholme IDB Yorkshire Water Association DEFRA Lincolnshire Wildlife Trust Yorkshire Wildlife Trust Doncaster and District Angling National Farmers Union Wroot Parish Council Association Doncaster Metropolitan Natural England Borough Council INTERNAL ENVIRONMENT AGENCY SPECIALISTS Archaeology, Biodiversity, Flood Risk, Water Resources

A Consultation Document was distributed in May 2006. This outlined the purpose of the WLMP and asked each consultee a series of questions to establish their interests in the area, concerns regarding water level management, and potential impacts or constraints relating to water level management on Hatfield Moor. Table 16.2 provides a summary of responses to the Consultation Document.

Table 16.2 – Consultation responses

Consultee Summary of interest Key comments

Doncaster Local Planning Authority • Hold information in respect of all developments which Metropolitan (LPA) having both a have taken place in the Hatfield Moor area. This would Borough strategic interest in the include planning obligations and conditions which have Council site as the Competent been put in place to protect the water environment and Authority under the biodiversity of the Moor. Habitats Regulations and • Doncaster MBC has undertaken an Appropriate as the LPA dealing with Assessment for their first Development Plan Document individual planning under the Local Development Framework. matters and applications.

Environment Agency Hatfield Moor SSSI Water Level Management Plan Final Report [October 2006] 38

Consultee Summary of interest Key comments

Farmer Farms land adjacent to • At present, water management aims to avoid excess Hatfield Moor. water in winter and spring and retain water in summer for irrigation. • A considerable rise in water levels on the moors could affect ability to produce crops and graze livestock. Farming and Advise farmers on • No specific comments. Wildlife Environmental Advisory Stewardship in South & Group West Yorkshire. Hatfield Town Represent residents • No specific comments. Council within Hatfield Parish. Isle of Operational control of the • The IDB does not exert any direct control of water Axholme Keadby pumped area. levels in the drainage channels within or leading from Internal the SSSI. However, the IDB relies heavily on the Drainage operational control of water levels carried out by the Board Environment Agency within the Keadby pumped area, especially Bull Hassocks pumping station which received output from Greenholme Bank near Tunnel Pits. They do not wish to see reduction of flood protection standards in these systems. Landowner Agricultural land nearby • It is important how much water is in the dykes as it is and holds abstraction used for abstraction. licence. Landowner Arable farmer and • Agriculture depends upon drainage in autumn and landowner adjacent to early winter and irrigation in summer. An increase in SSSI. the water table would cause economic damage to land and reduce cropping options. • There has been more standing water on the moor in the past year with little or no apparent vegetation returning where peat has been extracted. Landowner Arable farmer and • There has been a much higher water table in recent landowner within SSSI years causing waterlogging of fields. Any permanent boundary. rise in water levels would make much of the farm unworkable and may increase the risk of flooding to property. Landowner Farmer and landowner • Fluctuating water levels adjacent to Lindholme Bank within SSSI boundary. Road may be causing subsidence and damaging the road. There is concern over who will be responsible for repairs and upkeep. Would like to see stable water levels in this area. • Would not like to see woodland compromised to create peat bog habitat.

Environment Agency Hatfield Moor SSSI Water Level Management Plan Final Report [October 2006] 39

Consultee Summary of interest Key comments

Landowner Landowner within SSSI • Lindholme Hall Cottages have an underground boundary sewage tank which recently been backfilling with water. • Since drainage of the land ceased, the area of water around the gas well compound has increased so that the compound is virtually an island. • There are concerns over increased flood risk to land and property. Lincolnshire Nature conservation sites • The Wildlife Trust welcomes the proposal to produce a Wildlife Trust within Lincolnshire. WLMP for Hatfield Moor SSSI. • The Trust would like to be involved if proposals will affect nature conservation sites within Lincolnshire. South Archaeological • Hatfield Moor is an area of national and international Yorkshire importance of site. archaeological significance. A Neolithic corduroy Archaeology trackway was found in 2004 and there are likely to be Service more sites of high archaeological importance. • Strategies are being formulated to ensure that the most appropriate treatment is afforded to the archaeological and palaeo-environmental remains on the Moor during Natural England’s restoration works. • Any works proposed should facilitate implementation of such strategies. Thorne & Acts an umbrella for a • Good quality surface water should not leave the site. Hatfield Moor wide range of Clearer understanding is required of relationship Conservation organisations such as between groundwater and surface water. Forum Wildlife Trusts and • The SSSI should not be considered in isolation but in natural history societies. the context of the wider Hatfield Chase area. Interest in conservation • A high and stable water table should be maintained to of Hatfield Moor including preserve archaeological features. biodiversity, geological • Consideration should be given to water chemistry and and archaeological pH in the context of site restoration and ecology. features. Tyram Fisheries Manage fishing lakes • Would be concerned over any activities affecting water bordering Hatfield Moor supply to the lakes. Water levels have fallen over the SSSI. past few years due to a combination of low rainfall and lack of run off from drains from Hatfield Moor and surrounding area. • It is important for future water levels to be maintained for fish and other wildlife. Wetland Interest in the future of • WAERC are currently undertaking research into the Archaeology the Moors from an potential for in-situ preservation of archaeological and archaeological remains in wetland/ waterlogged environments. Environments perspective. Centre (WAERC) Wroot Parish Represent residents • No specific comments. Council within Wroot Parish.

Environment Agency Hatfield Moor SSSI Water Level Management Plan Final Report [October 2006] 40

16.2 Project Board

A Project Board will be set up to include representatives from the Environment Agency (flood risk, water resources and biodiversity teams), Natural England, Hatfield Chase IDB and Yorkshire Water. Other stakeholders can be added to this group as necessary. The purpose of the Project Board is to meet quarterly to make decisions on how the WLMP will be implemented.

Environment Agency Hatfield Moor SSSI Water Level Management Plan Final Report [October 2006] 41

Glossary of terms and abbreviations

Acrotelm Undamaged (undrained and uncut) raised bogs often consist of two soil layers: an upper acrotelm and a lower catotelm. Definitions of acrotelm and catotelm vary and there is no agreement between ecologists and hydrologists on exactly how the terms should be used. Hydrologically, the acrotelm is the zone in which the water table fluctuates. In undamaged bogs it consists usually of poorly-decomposed Sphagnum litter and peat with an open pore structure and a relatively high permeability. The catotelm is that part of the peat profile below the lowest (drought) water table. Typically it consists of well-humified peat with a relatively low permeability. In cutover bogs, the definitions become hard to apply. During peat extraction, the acrotelm is usually entirely removed leaving the catotelm. However, with drainage, the water table will fall into what was the catotelm. There then exists at the bog surface well- humified, poorly-permeable peat in which the water table fluctuates (i.e. a combination of the definition of the acrotelm and catotelm in an undamaged bog). Anaerobic A biological process which occurs in the absence of oxygen. Biodiversity An agreed plan for a habitat or species, which forms part of the UK’s commitment to Action Plan biodiversity. For further information consult the BAP website: (BAP) http://www.ukbap.org.uk/aboutBAP.htm Catotelm See entry for acrotelm. Conservation Objectives set by Natural England defining the desired state for a particular SSSI in Objectives terms of features for which they may have been designated. When features are being managed in a way which maintains their nature conservation value, then they are said to be in ‘favourable condition’. Environmental A stand alone report or section within an Environmental Statement or Report which Action Plan ensures that constraints, objectives and targets are translated into contract (EAP) documents and practiced on the ground. Environmental The process, by which the likely impacts of a project upon the environment are Impact identified, collated, measured and assessed to determine their significance. The Assessment analysis of predicted environmental effects enables different options to be (EIA) considered, together with identification of the scope for optimising positive effects and mitigating negative effects during the project design. Environmental An Environmental Report is produced for projects that do not require an Report (ER) Environmental Statement, including for projects requiring planning permission from a local authority and where the effects of the proposal will not be significant. The ER is similar in content but less detailed than an Environmental Statement. Favourable Favourable condition means that the SSSI land is being adequately conserved and is Condition meeting its 'conservation objectives'. However, there is scope for the enhancement of these sites. General Quality The Environment Agency assesses river quality using a survey called the General Assessment Quality Assessment (GQA) scheme. This measures four aspects of river quality – (GQA) biology, chemistry, nutrients and aesthetic quality. We monitor the quality at about 7,000 sites representing about 40,000km of rivers and canals in England and Wales. Groundwater Water occurring below ground in natural formations (typically rocks, gravels and sands). Often a distinction is made between soil water and groundwater, where the latter is any water below the water table. Hydrogeology The study of groundwater and its movements. Hydrology The study of water in rivers, streams, lakes, at or below the surface. Hydrophobic Repels water Local Planning The government has given the main responsibility for planning to local authorities. A Authority Local Planning Authority is responsible for deciding whether a development should go ahead; i.e., whether planning consent is granted following an application.

Environment Agency Hatfield Moor SSSI Water Level Management Plan Final Report [October 2006] 42

Main river Watercourses defined on a ‘Main River Map’ designated by DEFRA. The Environment Agency has permissive powers to carry out flood defence works, maintenance and operational activities for Main Rivers only. Responsibility for maintenance, however, rests with the riparian owner (the land owner). Mitigation Steps that may be taken to minimise, eliminate or compensate for the adverse Measures effects of a development. National The NVC is a system of classifying natural habitat types according to the vegetation Vegetation they contain. It is based on the presence of particular plant species. Each broad Classification vegetation type (e.g. woodland) is broken down into communities, designated by a (NVC) number and name (e.g. W6 Alnus glutinosa – Urtica dioica). Ombrotrophic Rain-fed. Scheduled An archaeological monument that is included in the Schedule maintained by the Ancient Secretary of State under Section 1 of the Ancient Monuments and Archaeological Monument (SAM) Areas Act 1979. Such monuments are protected by law. Scoping The process of deciding the scope and level of detail of the study including the environmental effects and options to be considered, assessment methods to be used, and the structure and contents on the resulting Environmental Statement or Report. Screening The process of deciding which development requires an EIA to be carried out and at what level of detail. Sites and The SMR is a computerised database containing information on known Monument archaeological sites, historic landscapes and listed buildings. Record (SMR) Site of Special Sites protected under the Wildlife and Countryside Act 1981 and Countryside and Scientific Interest Rights of Way Act 2000. (SSSI) Unfavourable The special interest of the SSSI unit is not being conserved and will not reach declining favourable condition unless there are changes to management or external pressures. condition The site condition is becoming progressively worse. Water Level A document setting out water level management requirements in a defined floodplain Management area (usually a SSSI) which is designed to reconcile different requirements for Plan (WLMP) drainage. Wildlife and The Wildlife and Countryside Act 1981 (as amended) is the principal mechanism for Countryside Act the legislative protection of wildlife in Great Britain. The Wildlife and Countryside Act is divided into four parts:

• Part I is concerned with the protection of wildlife, • Part II relates to the countryside and national parks (and the designation of protected areas), • Part III covers public rights of way, • Part IV deals with miscellaneous provisions of the Act The designation of protected species is included in Schedules 1, 5 and 8 of the Act, which list protected birds, protected animals and protected plants, respectively.

Environment Agency Hatfield Moor SSSI Water Level Management Plan Final Report [October 2006] 43

References and Bibliography Cathcart, R (2004) Achieving the Public Service Agreement Targets for SSSIs: as review of the contribution of Water Level Management Plans. A report to DEFRA and Natural England.

Dinnan, MH and Whitehouse, NJ (2000) SSSI boundaries of the Humberhead Peatlands: the palaeoecologial and archaeological significance of the raised mires of Thorne and Hatfield Moor, and associated considerations. Thorne and Hatfield Moor Conservation Forum Report Number 5.

Holden, J; Chapman, PJ and Labad, JC (2004) Artificial drainage of peatlands: hydrological and hydrochemical process and wetland restoration. Progress in Physical Geography 28 (1) pp 95– 123.

Natural England http://www.english–nature.org.uk/special/sssi

Entec (2003) Thorne Moor and Hatfield Moor Water Balance Models. Report for Yorkshire Water Services Ltd.

Environment Agency http://www.environment-agency.gov.uk

European Commission DG Environment (2003) Interpretation manual of European Union habitats (version EUR25). European Commission DG Environment, Brussels. http://europa.eu.int/comm/environment/nature/nature_conservation/eu_enlargement/2004/pdf/ha bitats_im_en.pdf

JNCC, (2004), Common Standards Monitoring Guidance for Lowland Wetland, Version August 2004, ISSN 1743-8160 (online)

JNCC, (2005), Common Standards Monitoring Guidance for Freshwater Habitats and Species, 1st version - March 2005, ISSN 1743-8160 (online)

Limbert, M. 1978. A Peat Moor Study: Hatfield Moors. Part 1 Geology and Geomorphology. The Lapwing, 11, pp 36-39.

Lindsay, AJ (2000) Thorne and Hatfield Moor SSSIs. The case for continued statutory protection: a summary. Thorne and Hatfield Moor Conservation Forum technical Report Number 3.

Morgan-Jones, W; Poole, JS and Goodall, R (2005) Characterisation of hydrological protection zones at the margins of designated lowland raised peat bog sites. JNCC Report No 365.

Mott MacDonald (2006) Hatfield Moor: Habitats Investigation Inception Report. Report for Yorkshire Water Services Ltd.

Posford Duvivier Environment (2000) Lowbank Sub-Catchment Hatfield Chase Water Level Management Plan.

Environment Agency Hatfield Moor SSSI Water Level Management Plan Final Report [October 2006] 44

Posford Duvivier Environment (2000) Candy Farm North Water Level Management Plan - Deposit Draft.

Posford Duvivier Environment (2000) Tunnel Pits South Sub-Catchment Hatfield Chase Water Level Management Plan - Deposit Draft.

Posford Duvivier Environment (2000) Tunnel pits North Sub-Catchment Hatfield Chase Water Level management Plan - Deposit Draft.

Smith, B (1985) A palaeoecological study of raised mires in the Humberhead Levels. Unpublished PhD thesis, University of Wales.

Van De Noort R, and Ellis S (1997) Wetland Heritage of the Humberhead Levels, An Archaeological Survey.

Environment Agency Hatfield Moor SSSI Water Level Management Plan Final Report [October 2006] 45

APPENDICES

Environment Agency Hatfield Moor SSSI Water Level Management Plan Final Report [October 2006]

Appendix A Hatfield Moor SSSI Citation

Environment Agency Hatfield Moor SSSI Water Level Management Plan Final Report [October 2006] Date Notified: 18 November 1988

File ref: SE 60/2

County: South Yorkshire Site Name: Hatfield Moors

District: Doncaster

Status: Site of Special Scientific Interest (SSSI) notified under Section 28 of the Wildlife and Countryside Act, 1981.

Local Planning Authority: Doncaster Metropolitan Borough Council

National Grid Reference: SE 705060 Area: 1400.7 (ha) 3461.1 (ac)

Ordnance Survey Sheet 1:50,000: 111, 112 1:10,000: SE 60 SE, SE 60 NE, SE 70 SW, SE 70 NW

Date Notified (Under 1949 Act): 1954 Date of Last Revision: 1977

Date Notified (Under 1981 Act): 1982 Date of Last Revision: 1988

Other Information: The boundary of this site has been changed as a result of a large extension.

Description and Reasons for Notification: Hatfield Moors, like Thorne and Crowle Waste, is a remnant of a once extensive lowland raised bog which once occupied the Humberhead levels. It is situated 10 km east of Doncaster and for the most part lies close to sea level.

The site encompasses the peatland of Hatfield Moor together with a system of drainage ditches within adjacent agricultural land.

Lowland peat bogs are a nationally rare habitat with none occurring in lowland England in completely unmodified form, most having been cut for peat. Although of secondary importance to Thorne, Goole and Crowle Waste in its overall scientific interest Hatfield is unique in having developed directly upon nutrient deficient gravels without an initial reed swamp phase. Hatfield Moor is the second largest remaining raised bog in lowland England; Thorne, Goole and Crowle Waste being the largest. It is now known that rehabilitation of raised bog and heathland habitats is possible following peat winning and therefore the bare peat surfaces are regarded as having considerable potential value for nature conservation. The site has also been notified because of its important breeding bird and insect populations.

Much of the peatland section of this site is cut for peat yet a restricted representative flora and fauna persists within a mosaic of mire and dry heath habitats beneath birch scrub. The mire communities are dominated by cotton grasses Eriophorum vaginatum and E. angustifolium, cross-leaved heath Erica tetralix and bog mosses Sphagnum spp., but include species rare in the county such as cranberry Vaccinium oxycoccus, bog myrtle Myrica gale and bog rosemary Andromeda polifolia. Dry heath communities are dominated by heather Calluna vulgaris, purple moorgrass Molinia caerulea and bracken Pteridium aquilinum. The ground flora of more mature birch scrub includes climbing corydalis Corydalis claviculata and broad buckler fern Dryopteris dilatata.

The site supports a diverse breeding community of heathland birds of which the population of nightjars is a particular highlight, and may be of international significance. Nightingales breed here on the northern limit of their range and three species of owl have been known to nest.

The Moors are of national importance for invertebrates, supporting eight Red Data Book species, associated with habitats ranging from the bare peat eg the beetle Bembidion humerale to deciduous and mixed woodland eg the beetle Pryopterus nigroruber, notable species include the bog rush cricket Metrioptera brachyptera and the large heath butterfly Coenonympha tullia.

The system of drainage ditches within the site represent the most diverse running water habitat in South Yorkshire and exhibits an unusual combination of acid and base rich aquatic plant communities. An unusually rich collection of Potamogeton pondweeds occur, 12 species having been recorded including, for example, longstalked pondweed P. praelongus, reddish pondweed P. alpinus and shining pondweed P. lucens which are scarce in the county.

Associated submerged species include greater bladderwort Utricularia vulgaris, arrowhead Sagittaria sagittifolia and the nationally rare short-leaved water starwort Callitriche truncata. There is also a diverse emergent and marginal vegetation including Eleocharis acicularis, brown sedge Carex disticha and cyperus sedge Carex pseudocyperus. Hatfield Moor SSSI - Favourable Condition Table Water Level management features only

Interest Criteria Attributes Measures Targets Comments (operational) feature feature

Degraded Bog Active peat Vegetation Ombrotrophic Sphagnum cover to be not Re-instate a cover of plant species as Rounded judgements have to be made in capable of formation composed less than 10%, with cotton grasses guided by those found in the assessing average values for water level natural predominantly (Eriophorum angustifolium, E underlying peat strata, being indicative relative to ground level as most bog regeneration of species vaginatum) accounting for the greater of what has formed peat in this location surfaces are soft and uneven. as a precursor capable of proportion of the remainder (excluding in the past. They will include but not of active peat the rand). exclusively be Sphagnum mosses and A diffuse growth of stunted birch, bracken raised bog. formation. cotton grasses. or other ‘invasive’ species does not Every six years survey quadrats in or constitute unfavourable condition. The net permanent belt transects through Bog water should be stagnant, close to accumulation compartments covering observed surface ground level and indicative of Where removing scrub is in conflict with of peat. variation to determine the cover of the anaerobic conditions; the water table the requirements of nightjars and above species. should normally be within approx 10 invertebrates appropriate balances have to cm of the surface. be struck and targets modified accordingly. Read a diametric transect of dipwells However, there will be thresholds beyond monthly. The mean free groundwater Bracken and scrub should be dominant which the retention of trees and scrub will level should not fall more than 25 cm over no more than 10% of the mire severely compromise the health of an active below surface level, taken as an average expanse unless tree/scrub is essential bog over the mire expanse (excluding the for other interest features such as rand), in more than one year in five. nightjar and invertebrates. Active bog status is MANDATORY in respect of favourable condition. Approximately 80% of the mire expanse should be active to achieve favourable condition.

Interest Criteria Attributes Measures Targets Comments (operational) feature feature

Degraded Bog Macrotope landform in Stable water levels around the edges of The re-instatement of an undrained Hatfield Moor is underlain by sands and capable of which the the raised bog, close to ground level. area around the raised bog (Hatfield clays. Historic records and study of soils natural raised bog Water levels in ditches not to fall more Moor) to bear fen, wet grassland, wet around the bog will determine its ecological regeneration developed than 50 cm below ground level in more heath and wet woodland. and (by implication) hydrological context as a precursor than one year in five. before the contemporary land use was of active established. raised bog. Groundwater under the bog to be contiguous with the peat aquifer. Deduce This target is DISCRETIONARY as from comparison of water level regards condition assessment but its behaviour in piezometers at a range of establishment may have implications for the depths well-being of the bog via a common (The Environment Agency are hydrology. monitoring this). To do this would require management over An appropriate habitat such as fen to the whole hydrological unit, however surround the bog for such a distance as unless the surrounding land is notified as hydrological studies recommend. well it will be difficult to achieve this. Lowland water Characteristic water levels to be Ideally, depth gauges should be The levels characteristic of the site, in ditch availability maintained. Generally, in wet ditches inserted in ditches at strategic points, relation to both freeboard and water depth, systems summer water depth at least 0.5 m in including the main feeder. During the should be maintained. High water levels are minor ditches and 1 m in major drains. structured walk, water levels should be particularly important in spring and early 90% of channel length should reach this recorded using these gauges and/or by summer for semi-aquatic riparian target. probing ditches with a pole marked in invertebrates. Except for parts of the ditch quarter metre intervals. system that dry up naturally in the summer or are being allowed to succeed to swamp in a long management rotation or are influenced by tidal flow, a good depth of water should be maintained. If the site is used as a wash, or if ditches within it are used as reservoirs by the drainage authorities or the land manager, periodic

Interest Criteria Attributes Measures Targets Comments (operational) feature feature flooding or high water levels will be encountered. Where there is a Water Level Management Plan for the site, satisfactory implementation of the plan should be included as a target within the conservation objectives. Lowland Water quality Water quality underpins the status of many ditch of the interest features in ditches. systems Lowland a) water Water clear or only slightly Along the structured walk note Both turbidity and coloration are recorded ditch clarity turbid/discoloured in at least 90% of unnatural turbidity or discoloration of under this attribute. Blooms of planktonic systems channel length water. For each sub-section, record % algae cause reduced water clarity. Ochre of the length (to nearest 5%) with clear deposits in peaty areas can also cause water, % with slight discoloration. Brown coloration of the turbidity/coloration and % with marked water in acid peat areas is natural, so should turbidity/coloration. The overall result not be regarded as discoloration. is the mean of each set of figures from the sub-sections. Lowland b) extent of Mean cover of filamentous macro-algae For each structured walk sub-section, in The effect of excessive nutrient enrichment ditch algal and Enteromorpha not more than 10% freshwater ditches only, estimate % is often signified by increased prevalence of systems dominance (mid June to end August) cover of the channel (to nearest 5%) by algae, either filamentous or planktonic. filamentous algae and Enteromorpha Algae such as Enteromorpha are not good species taken together. Occasional indicators in saline conditions. Charophytes sampling of the vegetation by grapnel are not included in the group of macro- may be necessary. The overall result is algae indicative of nutrient enrichment the mean of cover values for the sub- because they need clear water. sections.

Appendix B Available monitoring data

Environment Agency Hatfield Moor SSSI Water Level Management Plan Final Report [October 2006]

Monitoring is undertaken by Natural England, Environment Agency and Yorkshire Water Services. Monitoring locations are shown on Figure B1 and details of available data are given below (information from Mott MacDonald, 2006).

Time period and Data type Details Source Comments frequency GEOLOGY Drift BGS project to map drift n/a BGS EN has commented that geology deposits caution should be applied when interpreting this data. CLIMATE Rain Data from Crowle and 1941-present EA gauge Lindholme and other locations surrounding Hatfield Moor MORECS AE, PE, rainfall, SMD Weekly totals for YWS 40km x 40km grids and other factors for period 1993 – square 100 (and 108) 2006 Weather Unknown Unknown EN station SURFACE WATER Levels Installations at 10 15 minute YWS YWS /MM are creating two locations in drains around intervals between new SWLs stations and Hatfield Moor and one March 2005 and resurveying existing boards lake present Levels Installations at 5 Unknown EN locations Levels and Logger data for ditches 15 minute EA Data has not been calibrated flows around Hatfield Moor (5 intervals between as there is little flow within the locations) March 2005 and ditches. A more sensitive flow present meter has been purchased Pumping Pumping and let back Daily between EA IDBs also supply pumping station volume data calculated May and data to the EA. data from Environment September (1999 Agency model for 13 to 2005) pumping stations. GROUNDWATER Boreholes Network of nested Hourly between YWS Downloaded bi-monthly by boreholes. 5 locations, April 2005 and Ewans Group Plc. each with three present boreholes (shallow, medium and deep) Monitors groundwater Monthly EA EA datums have been levels in Sherwood Time period amended. sandstone in Hatfield unknown Moor and surrounding area. Dipwells Dipwells anchored in the Fortnightly data EN EN has advised that these drift but are measuring collected from may now only be monitored water levels in the peat 1986 to present monthly. (most data starts Data loggers are due to be in 1995) installed in future.

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Appendix C Cultural heritage review

Environment Agency Hatfield Moor SSSI Water Level Management Plan Final Report [October 2006]

D.1 Sources of information The following sources of information were consulted:

• National Monuments Record (NMR); • South Yorkshire Historic Environment Record; • Early Ordnance Survey maps; • Aerial photographs of the study area provided by the Environment Agency • A review of previous published and unpublished specialist reports. Details of these are provided in the bibliography.

• Consultation was also undertaken with South Yorkshire Archaeological Service.

D.2 Known Cultural Heritage Sites A total of sixteen sites of cultural heritage interest have been identified within the study area. A summary of these is provided in the table below and the locations are shown on Figure C1.

Site Site Name Site Type NMR Number Importance

Lindholme Bank Road 1 Archaeological Evaluation 966093 None Evaluation

Hatfield Moor Gas Pipeline Desk 2 Archaeological DBA 1333712 None Based Assessment (DBA)

3 Isle of Lindholme Flint Axehead Findspot N/A Local

Hatfield Moor Site 1 Palaeoenvironmental 4 Palaeoenvironmental Sampling N/A National Sampling Site Site Hatfield Moor Gas Storage 5 Archaeological Evaluation 13335369 None Facility Evaluation Hatfield Moor Site 2 Palaeoenvironmental 6 Palaeoenvironmental Sampling 1385296 National Sampling Site Site

7 Hatfield Sand and Gravel Pit Sand and Gravel Pit SE 60 NE 41 Local

Middle Ring Drain Ridge and 8 Ridge and Furrow (Site of) SE 60 SE 24 Local Furrow

Area of Archaeological 9 Isle of Lindholme N/A Unknown Potential East of Isle of Lindholme Palaeoenvironmental 10 Palaeoenvironmental Sampling N/A National Sampling Site Site Lindholme Hall Cottages Palaeoenvironmental 11 Palaeoenvironmental Sampling N/A National Sampling Site Site Packards South Transect Palaeoenvironmental 12 Palaeoenvironmental Sampling N/A National Sampling Site Site

13 Isle of Lindholme Trackway Trackway N/A National

Environment Agency Hatfield Moor SSSI Water Level Management Plan Final Report [October 2006]

Site Site Name Site Type NMR Number Importance

14 Lindholme Bank Road Pond Pond SE 60 NE 41 Local

15 Moor Bank Flint Axehead Findspot SE 70 SW 10 Regional

16 Lindholme Hall Hall N/A Regional?

No World Heritage Sites, Scheduled Monuments, Listed Buildings, Historic Battlefields or Registered Parks and Gardens are located within the study area. While the number and importance of known sites within the study area are comparatively low, this is more a reflection of lack of visibility of these sites than their absence. The cultural heritage importance of the study area is therefore largely based on its potential.

The following observations were made from the available information:

• One of the most important known archaeological sites within the study area is the Isle of Lindholme Trackway (Site 13). Identified in 2005, this comprises a 50m section of timber trackway leading to a timber platform. Dated to the Late Neolithic period it is possible that this trackway was built in response to wetter climatic conditions to allow continued access across the bog or to allow access to an isolated activity area. While not designated as a Scheduled Ancient Monument, given the date, rarity and fragility of this site, it has been assessed as being of National Importance.

• The Isle of Lindholme (Site 9) is a morainic ridge which stands slightly higher than the surrounding landscape. As such this area is comparably drier, and has long been considered as a suitable place for prehistoric settlement (Van de Noort and Ellis 1997, 380). However, evaluation excavation in this area (Site 1) did not identify any features of archaeological importance. Antiquarian sources refer to a trackway traversing Hatfield Moor linking Lindholme to adjacent drier ground (Dinnan and Whitehouse 2000).

• Lindholme Hall (Site 16) on the Isle of Lindholme is marked on early Ordnance Survey maps. This may have been the site of the hermitage of William of Lindholme (Van de Noort and Ellis 1997, 380), dating to the later medieval period.

• Waterlogged deposits such as peat can preserve pollen, phytoliths, diatoms, and large and small fragments of vegetation. This evidence can be used to reconstruct the environment in the past (the palaeoenvironment) at a local, regional and national scale, and how it changed over time. Areas where peat may occur should therefore be considered to have a potential for the presence of palaeoenvironmental deposits. Palaeoenvironmental evidence is of high cultural heritage value because it enables changes in the archaeological record to be linked to changes in the environment, and to identify the influence of human activity on the environment. These deposits are also extremely fragile and the upper levels prone to desiccation.

• Sites 4, 6, 10, 11 and 12 are the locations of palaeoenvironmental sampling sites resulting from a number of palaeoenvironmental studies undertaken within the study area (Smith 1985, Van de Noort and Ellis 1997). These have established that peat developed in the area in the late 4th and early 3rd millenniums BC. While there is little evidence for pre-mire landscape, it is thought that pine forest and heath predominated, with some local areas of oak woodland. As

Environment Agency Hatfield Moor SSSI Water Level Management Plan Final Report [October 2006]

conditions got wetter, either as a result of climatic deterioration or local changes in the water table, some peat developed, with pine and birch woodland invading a relatively dry mire surface (Van de Noort and Ellis 1997, 188). There is also evidence for burning of this woodland, although it is not known whether this resulted from natural or human action. By the beginning of the third millennium BC, around the time the Isle of Lindholme Trackway was constructed, the forest and heath had been replaced by mire.

D.3 Cultural Heritage Potential of the Study Area Based on the known sites of cultural heritage interest within the study area and sites in the surrounding area, such as the Bronze Age trackway on Thorne Moor and bog bodies from the area around Hatfield Chase, the potential of the study area for undiscovered archaeological remains of prehistoric and later date had previously been identified (Van de Noort and Ellis 1997, Dinnan and Whitehouse, 2000). This potential was partially realised by the discovery of the Isle of Lindholme Trackway (Site 13).

Important archaeological sites can occur at any level within the peat deposits, or on the pre-peat ground surface. The whole of the study area, including areas previously milled, should therefore be considered to have a high potential for the presence of unknown archaeological deposits. This potential is reduced in areas where the peat and the underlying mineral land surface have been completely removed, such as in areas of modern development and in the quarries on the western edge of the study area.

Peat cutting and drainage has resulted in the destruction of the upper part of the peat archive, removing deposits spanning the historic and later prehistoric periods (Van de Noort and Ellis 1997, 380). However, in areas of limited disturbance, the palaeoenvironmental record extends from the prehistoric to the Medieval period (Dinnan and Whitehouse, 2000, 2). Such deposits are rare in Britain and should therefore be considered to be of national importance. Van de Noort and Ellis (1997, 164, 186) have identified four major areas of deep peat, although others are likely to exist:

• the south eastern part of the moor around New Moor South and New Porters Drain;

• Packards South Section; • Beltons Section and • the vegetated peatland to the North of Lindholme

In addition to the peat deposits, any buried trees preserved by the peat can provide information of past climate and vegetation cover and also contribute to the development of dendrochronologies. As such, these are considered to be of importance at a national scale.

D.4 Outline Recommendations The cultural heritage resource within the study area has been assessed as being of national importance. This assessment is based on:

• known archaeological sites of national importance within the study area; • a high potential for the presence of unknown nationally important sites in the peat and on the pre-peat landscape;

Environment Agency Hatfield Moor SSSI Water Level Management Plan Final Report [October 2006]

• known and potential deposits of palaeoenvironmental importance, including peat deposits and trees preserved by the peat.

It is recommended that an Archaeological Management Plan for Hatfield Moor is undertaken to inform the WLMP and future management.

Appropriate water level management will be beneficial for the preservation of the cultural heritage resource within the study area. However, works to enable restoration, including construction of sheet pile dams, peat bunds, construction of new drains or maintenance of existing drains, and temporary accommodation works could potentially have an adverse impact on the resource. At present there is insufficient information to assess the significance of any potential impacts.

Given the importance and sensitivity of the study area, in advance of any works detailed consultations should be undertaken with South Yorkshire Archaeological Service and the English Heritage Regional Scientific Advisor.

While problems of identifying archaeological sites under and within the peat are recognised, in the event that any construction works are proposed, the first stage in obtaining the required information is likely to be a desk-based assessment and walkover study. This would involve more detailed data collection and consultations, which may include the following:

• collection of more detailed information from the HER and SMR, including relevant reports on archaeological interventions;

• examination of historic maps and any other historic documentary evidence available from the South Yorkshire Archives and the Local Studies Library;

• examination of any relevant published historical and archaeological literature; • a detailed walkover survey and visual assessment; • additional qualitative consultation with the South Yorkshire Archaeology Service.

D.5 Evaluation Following completion of the desk-based survey report, and in agreement with South Yorkshire Archaeological Service, the Environment Agency’s archaeological advisor and Natural England, a programme of archaeological field evaluation is likely to be required. The possible range of works may include (without limitation) any of the following, or a combination of them:

• detailed assessment by, or consultation with, palaeoenvironmental specialists; • a programme of paleoenvironmental sampling and analysis, possibly including specialist coring and analysis to confirm the presence and significance of palaeoenvironmental deposits and • trial trenching or probing.

Environment Agency Hatfield Moor SSSI Water Level Management Plan Final Report [October 2006]

D.6 Mitigation The results of a programme archaeological evaluation would inform the nature and scale of the mitigation works. The range of mitigation options could include: • No further action; • design solutions to preserve remains in situ, which is the preferred option under PPG16; • design solutions to minimize any impact; • investigation and recording of remains in advance of development (including where necessary detailed archaeological excavation)

• investigation and recording of archaeological remains during the course of construction or any ground breaking works (including but not limited to an archaeological watching brief); or

• measures to ensure the long-term preservation in-situ of other remains in the immediate vicinity (i.e. incorporation in soft-landscaped areas)

Where preservation in situ is not feasible, then the appropriate mitigation strategy would be preservation by record, principally through detailed excavation in advance of construction.

Where archaeological deposits are discovered during construction, principally as a result of the archaeological watching brief, time and resources will need to be made available for the excavation and recording of any such deposits prior to their removal.

It is important to note that any archaeological works would necessarily include an element of post-fieldwork analysis and report-writing. This is usually most extensive for intrusive works (i.e. works that break the ground surface or involve the removal of archaeological objects from the site), and could include a requirement for the publication of a report in an academic journal.

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Appendix D Scope of proposed hydrological review

Environment Agency Hatfield Moor SSSI Water Level Management Plan Final Report [October 2006]

Hatfield Moor SSSI – Scope of proposed Hydrological Review Study

Introduction During the compilation of the Hatfield Moor SSSI Water Level Management Plan, it was identified that undertaking a hydrological review of the site would be useful to address some of the problems/issues that were raised in connection with the site. This type of study would have the potential to acquire a comprehensive understanding of the SSSI, and could therefore also be used to assist and/or improve the (development of) a management plan for the site.

The following text outlines the various tasks and activities that would typically be included in such a hydrological review.

Aims and Objective(s) The principal aim of the study would be to attain a comprehensive overview of the (hydrological) operation of the Hatfield Moors site, focusing on the interaction of surface water and groundwater, existing storage and hydraulic operations on the site. Additionally, the study would identify potential issues with the site in connection with the (proposed) restoration work, and mitigating measures to tackle these issues.

The main objectives would be;

• To identify conflicts between drainage system capacity (on and) around the Hatfield Moors site and the needs of various users

• To provide alternative solutions that could subsequently be costed and subjected to cost/benefit analyses

• To identify areas of land most suitable for wetland creation

Proposed Activities/Methodology To meet the above outlined aims and objectives, the following tasks and activities would need to be undertaken;

Data Collection and Review This item would include the review of available data to assist a conceptualisation of the site. This data availability would typically include hydrometric data (surface water and groundwater level data, pumping station data, rainfall data etc), drain capacity data, digital elevation data (LiDAR) etc.

It is understood that for the Hatfield Moors site LiDAR data is readily available, but that sufficiently detailed drain capacity data would still need to be obtained for the study. It is envisaged that drain capacity data could be obtained during intensive visits to the site or by commissioning a channel survey from a surveying contractor.

Assessment of Drainage Area This item would typically include the following sub-activities;

• Catchment delineation based on available data (i.e. LiDAR) and (a) discussion(s) with English Nature (Natural England)

• Investigation of surrounding (IDB) drainage catchments

Environment Agency Hatfield Moor SSSI Water Level Management Plan Final Report [October 2006]

• Identifying areas that are difficult to drain (and could potentially be used for wetland creation) (I)

• Assessment of groundwater drawdown (desk study based on available dipwell and borehole data)

• Identifying areas difficult to drain (II), based on the hydrogeological assessment

• Hydrological modelling (rainfall-runoff), e.g. based on the Rational Method (which would also include an estimation of runoff coefficients for the site based on soil conditions)

• Volumetric assessment of the site, targeted on different rainfall return periods

Consideration of Different Drainage Scenarios This item would include a comprehensive assessment on the potential effects of the proposed restoration works for the site. This assessment would typically involve an investigation on likely increased runoff (i.e. (site) sensitivity analysis) followed by various proposals for alternative drainage scenarios.

Potential Wetland Habitat Creation This item would include a comprehensive consideration of potential wetland habitat creation for the site(s) identified during the drainage areas assessment task.

Conclusions and Recommendations

This item would typically include recommendations and conclusions on the proposals for alternative drainage scenarios. This could involve recommendations for possible installation of water control structures, or changes to current pumping regimes etc.

This item would also include proposals for further work.

Reporting and Project Management

This item would include the production of a hydrological review report and the general management of the study (e.g. project financial control, progress meetings/reporting etc)

Optional increased level of a Hydrological Review Study

Option 1: Hydrological Review study with increased level of hydrogeological assessment

This level of study would replace the previously mentioned groundwater drawdown desk study with a comprehensive groundwater model for the site (e.g. using MODFLOW).

Option 2: Hydrological Review Study incorporating comprehensive hydrodynamic modelling

This level of study would provide a more detailed conceptualisation of the site based on a hydrodynamic model of the drainage network and pumping regime.

Additional tasks and activities would typically include;

• An increased level of survey of the drainage network

• Hydraulic model development

• Hydraulic model calibration

• Option runs

• Flood mapping

Environment Agency Hatfield Moor SSSI Water Level Management Plan Final Report [October 2006]

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