UNITED UTILITIES SCaMP SUSTAINABLE CATCHMENT MANAGEMENT PROGRAMME MONITORING PROGRESS REPORT YEAR 4

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1 UNITED UTILITIES SCaMP SUSTAINABLE CATCHMENT MANAGEMENT PROGRAMME MONITORING PROGRESS REPORT YEAR 4 Penny Anderson Associates Limited Park Lea 60 Park Road Buxton Derbyshire SK17 6SN Project Manager Penny Anderson This project has been undertaken in accordance with PAA policies and procedures on quality assurance. Signed: 1

2 C O N T E N T S SUMMARY 1. INTRODUCTION 1.1 What SCaMP is about Background to the SCaMP Project Estates SCaMP Project Monitoring The Project Drivers Project Implementation 1.2 SCaMP Hydrological and Vegetation Monitoring The Monitoring Programme SCaMP Monitoring Hypotheses The Scale of the SCaMP Monitoring 1.3 Report Structure The Themes Adopted The Report 2. RESTORING DRAINED AND GRAZED MOORLANDS BASELINE CHARACTERISATION: BRENNAND 2.1 Why Brennand? 2.2 The Brennand Catchment 2.3 Approach to the Hydrological Monitoring 2.4 Hydrological Baseline Conditions and Early Responses Climate Streamflow Discharge Groundwater Colour Groundwater Level Groundwater Levels Adjacent to Grips Streamflow Colour Streamflow Turbidity 2.5 The Vegetation Monitoring The Vegetation Monitoring Plots The Treatments Monitored Baseline Characterisation of the Peat Overall Vegetation Community Characteristics 2.6 Discussion 2.7 Concluding Remarks 3. RESTORING DRAINED AND GRAZED MOORLANDS EARLY RESPONSES TO CHANGE: THE GOYT 3.1 How the Goyt Fits in to SCaMP Assessments 3.2 The Goyt Catchment Character 3.3 Grip Blocking on the Upper Goyt 3.4 Climate and Runoff 3.5 Approach to the Hydrological Monitoring 3.6 The Hydrological Response 2

3 3.6.1 Groundwater Levels Streamflow Colour Streamflow Turbidity Streamflow Discharge 3.7 The Vegetation Monitoring Vegetation Monitoring Sites Treatments Monitored Changes in the Peat Soil Changes in the Structure of the Vegetation Changes in the Vegetation Community 3.8 Discussion 4. RESTORATION OF HIGHLY DEGRADED BLANKET BOG: NORTH LONGDENDALE 4.1 The Character of the Area 4.2 The Restoration Approach 4.3 The Monitoring Plot Locations 4.4 The Hypotheses Generated by the Restoration Works 4.5 Vegetation Monitoring The Vegetation Monitoring Sites A Comparison of the Effectiveness of Different Treatments on Early Vegetation Establishment 4.6 The Hydrological Responses to Restoration The Ashway Gap Catchment The Challenge Approach to the Hydrological Monitoring Results 4.7 Discussion Vegetation and Hydrological Response 5. LOOKING FORWARD 5.1 Continuation of the Monitoring 5.2 Development of Colour to DOC Rating Equations Methodology Results 5.3 Total Carbon Loss Calculations from Colour to DOC Rating 5.4 Turbidity to Particulate Organic (POC) Conversions for Catchment Carbon Budget 5.5 Commentary ACKNOWLEDGEMENTS REFERENCES APPENDICES 1 Vegetation Monitoring Methods 2 Hydrological Monitoring and Analysis Some Considerations 3 The Specification Used for Restoration Work on the Estates North of Longdendale 3

4 SUMMARY This report presents some of the results from the first four years (of a five year programme) of monitoring of (UU) Sustainable Catchment Management Programme (SCaMP). It focuses on the results of hydrological, water quality and vegetation monitoring on blanket bog on five estates in Bowland (Lancashire) and the Peak District (Derbyshire) associated with catchment-scale restoration works. The effectiveness of a number of other restoration methods in different habitats has been monitored and will be presented in a further report at the end of The key objectives of SCaMP are to meet the Government target of favourable condition for Sites of Scientific Interest (SSSI) by 2010 on UU s catchments, improve water quality, especially water colour but also sediment load and downstream flooding, ensure a sustainable future for the company s agricultural tenants and support UU s Biodiversity Strategy (itself cascaded down from the National Biodiversity Action Plan (BAP). The measures to achieve these objectives that are the focus of this report include large-scale blocking of drains (grips) and re-vegetation of extensive bare peat, both on blanket bog, and the introduction of more sustainable grazing regimes. Other restoration measures have been applied to non blanket bog BAP habitats and are being monitored, but will be the subject of a further report later in Three themes have been selected to represent the key findings in this report: determining the appropriate scale and nature of baseline characterization of catchments from a hydrological, hydrochemical and ecological perspective; the early responses to land management changes; and how highly degraded blanket bog catchment responds to extensive habitat restoration. The baseline characterisation prior to large scale grip blocking has been achieved on the Brennand catchment (Bowland). This has been followed by assessment of the early responses to the blocking together with grazing density reductions. The effects of grip blocking, stock reduction and cessation of burning have been studied on the Goyt Estate. This provided data during and after the implementation of the land management changes. The response to extensive restoration of highly degraded bare peat has been investigated on the estates North of Longdendale (Peak District). Baseline data were collected here prior to the works being carried out. Baseline characterisation The baseline hydrometric characteristics and conditions on Brennand listed below have been defined over a two year period to provide a high resolution reference against which to assess responses to land management changes within the catchment. This has shown that pre-grip blocking: the generation of water colour shows a statistically significant slight increase, even in the peat body of a relatively intact, non-gripped blanket bog area. This is in line with findings elsewhere and which generate concerns for water companies; the groundwater level in the peat body shows greater variation in the gripped sections of the catchment than the non-gripped sections; 4

5 the direct influence of gripping on peat groundwater levels tends to be limited to a zone of approximately m of the grip edge on this site; the generation of water colour within the peat body is driven by temperature (in particular) and the availability of air and water. In particular, as the water table rises to near the surface, the concentration of colour in the water increases exponentially; the stream discharge responds very rapidly to rainfall events prior to grip blocking; and an early response in the vegetation community to reduced grazing in summer is seen in an increase in wavy hair-grass (a particularly palatable species to sheep). Post grip-blocking (implemented only in winter 2008/9): the grip blocking work has changed the nature of the runoff regime in affected areas of the subcatchments. Early responses include: an increase in stream flow colour as a response to the works; a spike in stream flow turbidity associated with the grip blocking period followed by a decline to a more elevated (than pre-blocking) and variable background level; a reduced variability in peat groundwater levels resulting in wetter peat; and a reduction in colour in one sub-catchment in the groundwater in the peat, but this has not affected the stream flow colour. a possible change in the balance of heather and cotton-grass. The Brennand study has provided the only statistically viable characterisation of hydrological conditions within SCaMP prior to grip blocking which defines the nature, processes and behaviour of the catchment. Only the initial response has so far been monitored after grip blocking, which took place over a very short period. It is anticipated that the turbidity disturbance response will return to reduced background levels in time. Continuing the monitoring in 2010 will reveal the further response of stream water colour to the grip blocking. Vegetation changes to the grip blocking are expected to be slow and are not yet clearly apparent. In terms of meeting the targets set, the restoration measures implemented have set the blanket bog on a trajectory towards enhanced nature conservation condition, but it is too early to judge the effect on water quality and discharge rates. Responses to land management changes In the Upper Goyt catchment, land management changes occurred over two years before and during the early monitoring period, with nearly three years of data collected following completion of the works. The key responses to grip blocking and other management changes have been: the establishment of a higher, more stable water table in the peat body with reduced variations in seasonal water table levels; a general trend towards increasing cover of both Sphagnum and other mosses, some of which are statistically significant; 5

6 a statistically significant slight decline in stream water colour; and a significant shift in the streamflow regime with lower, post-treatment discharge levels. The hydrological changes are attributed largely to the grip blocking while the increase in mosses, an increased cover of some plants (eg. wavy-hair grass and bilberry) and an increase in the height of vegetation are considered to be attributable to reductions in summer grazing. The restoration works are considered to be meeting the target of moving the area towards more favourable condition in line with its SSSI status through re-wetting the peat and facilitating the spread of Sphagna, whilst at the same time contributing to improved water quality in terms of its colour. The reduction in streamflow could have significant implications for downstream flood risk management where such measures are implemented on a catchment scale. Restoration of highly degraded blanket bog In North Longdendale, where large-scale re-vegetation of bare peat has been implemented, with two years growth so far subsequently: the vegetation cover has increased significantly on fairly bare peat, mostly as a result of the nurse grasses, but heather is beginning to establish from the added seed and brash; there are some trends towards increasing moss cover and this is largely due to increases in Campylopus and to a lesser extent Hypnum jutlandicum; the use of geojute to stabilise the most vulnerable surfaces (<10% vegetation cover, on steep slopes) results in enhanced vegetation establishment; the application of either geojute or brash along with lime, seed and fertilizer, appears to improve the establishment of heather; turbidity levels in the Ashway Gap Small Clough monitored catchment show a small but statistically significant decrease in response to bare peat restoration works. 3.5ha of bare peat has been restored, reducing the area of bare peat within the catchment by 25%; colour levels in streamflow remain high and increasing slightly over the monitored period; and water table levels in the peat mass have responded positively to the re-vegetation of the bare peat surface. The effectiveness of the treatments indicate the initial response to restoration. From earlier trials nearby, it is anticipated that the nurse crops of grass and heather will gradually be replaced by local blanket bog species over the next 10 years. The reduction of turbidity found already is very promising and further monitoring will reveal the water colour response as the vegetation develops. The objective of restoring the degraded blanket bog is on course, but still in its early stages. The hydrological and ecological monitoring of all the SCaMP elements is programmed to continue through Further work is planned, including additional development of rating relationships (scatterplots) for dissolved organic carbon in relation to groundwater (in the peat) and raw stream water colour and similar rating relationship work to determine particulate organic carbon losses via suspended sediment and raw water turbidity measurements. The results of early calculations of changes in carbon losses resulting from the grip blocking works in the Goyt suggest significant reductions, which is of considerable significance in terms of carbon stores in peat and the associated ecosystem services. The results of this rating work will allow the final SCaMP report to present an analysis of carbon losses, including an assessment of the relative contribution of each carbon flux pathway to total carbon output in 6

7 the UK upland blanket peat environment. Such figures will enable SCaMP to demonstrate how the benefits derived from landscape scale management changes in the uplands may be interpreted and evaluated as a contribution to the principles of ecosystem services. The findings over the past four years from the hydrometric and vegetation monitoring across the SCaMP catchments provide a sound basis for concluding that such large scale land management changes may have significant environmental benefits in the medium and long-term, at both a local and national scale. It would appear that integrated land management changes in the uplands leads to improved water quality as well as re-establishing an upland hydrology that has the potential to contribute significantly to flood risk management. Combined with the restoration of upland habitats, SCaMP is demonstrating that these strategic management changes provide opportunities for sustainable environmental management. However, in order to provide an evidence base of a sufficient scale to enable policy makers to direct public and private funding confidently into this area, it is essential that the monitoring work on the SCaMP catchments has continued support for at least another five years. Not to capitalise on the resource base and monitoring programme that is currently in place would be a loss to the national momentum towards sustainably managing our landscapes to provide multiple benefits for future generations. 7

8 1. INTRODUCTION 1.1 What SCaMP is about Background to the SCaMP Project (UU) Sustainable Catchment Management Programme (SCaMP) is an innovative and large scale project that aims to improve catchment quality in terms of raw drinking water and nature conservation and to ensure a sustainable future for the company s agricultural tenants. It is a five year programme running from 2005 to 2010.The project is being undertaken principally in the Bowland Estate of UU s Central Region and much of its Southern Region in the Peak District (Figure 1.1). The project is funded through the Asset Management Programme (AMP4) and its broad aims are to: establish whether changes to land management practices that would benefit habitats and water quality can be achieved and, if so, by what means; establish the extent to which any changes: reduce the cost of existing drinking water treatment and avoid the need for additional treatment by improving the quality of water that is abstracted from the catchment; and improve the condition of land based Sites of Special Scientific Interest (SSSIs) and the ecological status of valuable wildlife habitats and species Estates UU is the largest land owner of the water companies, with 57,000ha. Much of the upland element of these Estates has been designated as Sites of Special Scientific Interests (SSSIs) for its dry dwarf shrub heath and blanket bog habitats and its upland breeding birds. Much of this area also lies in Special Areas of Conservation (SACs) and Special Protection Areas (SPAs). However 11,367ha of the SSSIs were in unfavourable condition at the commencement of SCaMP. In addition to these upland habitats, the Estates also support woodland of various types and a wide range of pastures and hay meadows. Some of these habitats contribute significantly to UU s Biodiversity Strategy targets (which are cascaded down from the National Biodiversity Action Plan (BAP). SCaMP covers 45 land holdings and 21 tenanted farms covering altogether 20,000ha in Bowland and the Peak District SCaMP Project Monitoring In order to establish the extent to which the measures being adopted in the SCaMP project are effective in achieving the objectives set, a monitoring programme was established to report on: the environmental effectiveness; the economic efficiency; and the wider lessons from the project. 8

9 (PAA) was charged with designing, carrying out, evaluating and presenting monitoring data on selected botanical and hydrological parameters for the SCaMP project. The RSPB are carrying out monitoring of the birds over selected areas of the Farm Plans. Figure 1.1 Overview of SCaMP Monitoring Project estates The Project Drivers From the ecological and hydrological point of view, the drivers of the SCaMP project are: to improve water quality, particularly water colour; to meet the Government s Key Performance Indicator (KPI) target of having 90% of SSSIs in favourable or favourable recovering condition by 2010; to support UU s Biodiversity Strategy by delivering actions on their wet and upland oak woodlands, rush pastures and upland flower-rich meadows and pastures; and to incorporate aims to reduce runoff rates, sediment load and downstream flooding. The issue of carbon retention and reduction of losses in peat degradation have increased in significance in relation to concern about climate change since the project commenced and are now seen as important drivers as well. 9

10 The monitoring programme that has been put in place has taken these drivers, applied them to the measures that are being implemented and set out to assess their effectiveness against the project s aims Project Implementation The mechanisms for undertaking the restoration and management measures are largely dependent on Farm Plans, with the measures incorporated into agri-environment schemes, either through the Higher Level Scheme, or through the existing Environmentally Sensitive Area schemes in the Peak District. The objectives of the Farm Plans are to: update the farm infrastructure to ensure that it is capable of supporting sustainable land management practice; implement low impact farming systems; restore catchment hydrology; and create habitats for a range of threatened wildlife. As well as the agri-environment scheme approach to implementation, the former English Nature financed some works independently, particularly grip 1 blocking. In addition, UU has used Forestry Commission Woodland Management Grants for undertaking measures to support BAP upland oak and wet woodland targets. The restoration measures applied included: re-wetting blanket bog (mostly through grip and drain blocking) to enhance its ecological condition and reduce the break down and subsequent loss of peat km of grips have been blocked in the Goyt (Peak District) and Bowland (Brennand and Whitendale); re-vegetation of eroding bare peat to restore a blanket bog vegetation, reduce sediment loss and improve water quality. 154ha have been treated and gully blocking will be carried out; reducing grazing pressure through stock reduction, removal or seasonal changes in grazing regimes to enhance the vegetation in terms of its diversity and cover. This covers 12,322ha of blanket bog and 7,564ha of dwarf shrub heath in Bowland and the Peak District; reversion of purple moor-grass-dominated moorland to a more diverse upland flora; woodland enhancement including removal of non native trees and shrubs or stock fencing in 111ha of existing woodlands; planting of new upland oak and wet woodland. 516ha of new woodland has been established to link or buffer existing areas and protect stream water quality; hay meadow improvements over 109ha through changes in management such as reduced fertiliser use, hay cutting and subsequent grazing management; and 1 grips are surface moorland drains, mostly established using grant aid in the mid 1900s. 10

11 management of 250ha of rush pastures by cutting to enhance the vegetation structure for breeding sites for waders. 1.2 SCaMP Hydrological and Vegetation Monitoring The Monitoring Programme The hydrological and botanical monitoring programme commenced in November The rationale was to monitor the effectiveness of most of the measures that have been implemented (as listed in 1.1) over the last four years. The grip blocking in Whitendale (Bowland) and some in the Goyt (Peak District) predated the start of the monitoring programme, but other measures post-dated this, thus providing opportunities for collecting baseline information. In some areas, reference or comparative sites were found which were not treated, or where stock were reduced but no grip blocking was carried out. This has permitted some comparison of treated and untreated areas. The following monitoring has been carried out at locations shown on Figures 1.2 and 1.3: the hydrological effects of grip blocking, including peat water tables, water colour, sediment loadings, stream discharge, rainfall and temperature in peat, grips and streams in Whitendale and Brennand in Bowland and in the Goyt Estate in the Peak District; botanical character of the same areas, including treated and untreated areas; vegetation cover, water quality in terms of sediment load and colour, peat water tables, rainfall and peat/water temperatures at sites on Ashway Gap, Quiet Shepherd and Arnfield Estates in the Peak District subjected to different bare peat re-vegetation treatments; vegetation response to reduced or altered stocking levels on Sykes and Lamb Hill Estates in Bowland; vegetation response to restoration of purple moor-grass to a more diverse vegetation in Goyt and Pikenaze, Peak District; progress in the restoration of upland oak and wet woodland at nine sites in Bowland and seven sites in the Peak District; vegetation response to enhanced management of upland hay meadows and pastures, seven sites in Bowland and two in the Peak District; vegetation response to structural and grazing pressure enhancements in rush pastures in Bowland (seven sites) and the Peak District (two sites); and pathogen levels in selected streams. The hydrological monitoring has frequently been continuous, but the botanical assessments have been more sporadic aligned with the generally slow change in vegetation after restoration measures have been implemented, or to tie in with when they were put in place. Not all sites or vegetation types were therefore monitored in The five year monitoring programme will be completed by the end of 2010 and a final report will cover all the features monitored. This report focuses on blanket bog and the hydrological and botanical effects of the restoration measures that have been implemented. 11

12 Figure 1.2 Overview of the Bowland SCaMP monitoring catchments Figure 1.3 Overview of the Southern SCaMP monitoring catchments 12

13 1.2.2 SCaMP Monitoring Hypotheses The drivers for the monitoring are derived from a series of hypotheses, as follows: blocking active grips will: move degraded blanket bog vegetation towards favourable condition through enhanced Sphagnum cover in wetter peat; raise the water table for longer; reduce colour (dissolved organic carbon DOC) in raw water; reduce suspended sediments (particulate organic compounds - POC) in raw water; and hold water in the blanket peat for longer, thus affecting the character of downstream flows; blocking gullies and re-vegetating areas of bare, eroding peat will: establish an initial vegetation cover on areas of bare peat allowing blanket bog species to colonise over time; reduce colour in raw water; raise the water table for longer; and reduce suspended sediments (POC) in raw water; reducing grazing will increase the height and cover of blanket bog and dwarf shrub species, including bryophytes, reduce damage levels to the vegetation and increase its capacity to retain water on the moor. These hypotheses have provided the project with a framework within which to specify the monitoring methodology and to analyse the resulting data in order to assess the effectiveness of land management changes The Scale of the SCaMP Monitoring The SCaMP Monitoring Project is nationally significant in its scale of spatial and temporal operation. Current SCaMP hydrological monitoring is conducted across four separate geographical sites and nine different treatment plot types. Intensively monitored data are currently collected from over 40 monitoring installations, with the current data series spanning over four years. Armstrong et al. (2010) state that previous studies investigating the impact of drain-blocking on water colour and dissolved organic carbon have been restricted to a limited spatial and temporal research framework. Their study provides one of the only other known examples of monitoring work undertaken at the scale of the current SCaMP monitoring project; with their study combining an extensive, UK wide survey of blocked and unblocked drains across 32 study sites and intensive monitoring of a peat drain system that had been blocked for seven years. In this context therefore, SCaMP is almost uniquely placed to provide intensively monitored, reliable data, for water colour, hydrology and carbon flux studies, which crucially run over long sampling timescales. 13

14 In the context of landscape sensitivity and the sometimes slow rate of change due to anthropogenic inputs, it is critical that data are collected over longer timescales in order to observe, characterise and assess the magnitude and timescale of system response and recovery. 1.3 Report Structure The Themes Adopted Over the past four years a significant environmental data resource has been established across the SCaMP monitoring catchments. From this resource, three themes have been selected to represent some of the key findings in this report. These are: identifying the appropriate scale and nature for establishing baseline characterisation of catchments from a hydrological, hydrochemical and ecological perspective. For this, the Brennand catchment in the Forest of Bowland provided the ideal opportunity to study hydrometrics prior to the implementation of significant land management changes. With the implementation of extensive grip blocking in 2008/9 winter, the early response is now being monitored against this baseline characterisation; identifying the early responses to land management changes. For this, the Upper Goyt Valley was subject to extensive land management change, in particular grip blocking and grazing and burning controls at the start of the project. This was therefore an ideal catchment to investigate the subtle responses in the hydrological and ecological character of the catchment; and identifying how a highly degraded blanket bog catchment responds to extensive habitat restoration. The land around and near to Chew Reservoir in the northern Peak District (Ashway Gap, Quiet Shepherd and Arnfield Moor) was selected by as part of a large scale moorland restoration programme, within which hydrological and vegetation monitoring has taken place The Report The three themes set out above represent a logical progression. Although the Brennand catchment was included in the monitoring programme in 2007 after the start of the project, it provided the ideal opportunity owing to its topography and character to compare the effects of land management changes across two sub-catchments with over a year available to characterise the hydrological and botanical features prior to works taking place. There were no other sites in the project where these data could be collected prior to the extensive grip blocking, which took place in the 2008/9 winter. Chapter 2 gives the results of this characterisation, but also assesses the responses to date of the grip blocking on the hydrology and vegetation. In contrast, the grip blocking and other land management changes that occurred in the Goyt Valley in the Peak District were in place when hydrological and botanical monitoring commenced. Although comparative sites have been selected where the grips have not been blocked, the data essentially provide information on four years since grips were blocked, managed burning was suspended and stock levels reduced. The results, thus, can be seen as representative of the next phase in the story of the effects of grip blocking and are presented in Chapter 3. The work on the estates north of Longdendale in the Peak District represent blanket bog at its most degraded and the results of the initial stages in establishing vegetation, which it is expected over time to move towards a dry blanket bog type over some 10 years (as found in earlier experimental studies, Anderson et al. 1997). The whole of this moorland block is severely gullied with much bare, eroding peat across a wide area. Much is considered to have been derived from wildfire over a long period of time, 14

15 including anecdotal accounts of fires burning for months after an aeroplane crash on Ashway Gap associated with the Second World War. The re-vegetation represents the first step in reducing erosion and peat loss, in regaining a moorland vegetation cover and in improving the water quality. The results are presented in Chapter 4. The final Chapter looks forward to the final year of monitoring and the expectations of the contribution that the project could make to the assessment of some of the ecosystem services, in particular changes in carbon and peat loss from the moors. 15