Bristol and Avon Rivers Trust
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Bristol and Avon Rivers Trust Somerset Frome Catchment Walkover Report June 2014 Document Control Document: Catchment Walkover Report Project: Somerset Frome Client: Bristol and Avon Rivers Trust Project number: 1667 Date of issue: June 2014 Prepared by: Ahern Ecology Ltd Unit 13 Hurricane Close Old Sarum, Salisbury SP4 6LG Website: www.ahernecology.co.uk Email: [email protected] Telephone: 01722 580008 Project manager: Rachel Whatmore Field team: Rachel Whatmore, Adam Ellis, Jessy Grant, Simon Browning GIS: Rachel Whatmore, Sean McGrogan Document checking Primary author: Rachel Whatmore Signed: Review by: Daniel Ahern Signed: Approved by: Daniel Ahern Signed: Catchment Walkover Report Ahern Ecology Ltd Contents Commented [AE1]: Update ‘page numbers only’ when finished Executive Summary ................................................................................................................................ 3 Double check formatting as font etc sometimes changes on updating 1.0 Introduction ........................................................................................ 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Bookmark not defined. 1.1 Introduction ................................................................................................................................ 4 1.2 Background ................................................................................................................................ 4 1.2.1 Water Framework Directive (2000/60/EC) .......................................................................... 4 1.3 Somerset Frome Overview ........................................................................................................ 5 1.4 Summary of Current EA WFD Data ........................................................................................... 6 2.0 Methodology .................................................................................................................................. 7 2.1 Point and Diffuse Pollution Sources .......................................................................................... 8 2.2 Barriers to Fish Migration ........................................................................................................... 8 2.3 Personnel ................................................................................................................................... 8 3.0 Results ........................................................................................................................................... 8 3.1 Overview .................................................................................................................................... 9 3.2 Grade 1 Sources ...................................................................................................................... 11 3.3 Grade 2 Sources ...................................................................................................................... 14 4.0 Discussion.................................................................................................................................... 19 4.1 Point Sources........................................................................................................................... 19 4.2 Diffuse Sources........................................................................................................................ 19 4.3 Barriers to Fish Migration and Connectivity ............................................................................. 19 5.0 Conclusions and Recommendations ........................................................................................... 20 6.0 References .................................................................................................................................. 22 Bristol and Avon Rivers Trust 1 June 2014 Somerset Frome Catchment Walkover Report Ahern Ecology Ltd 7.0 Appendices .................................................................................................................................. 23 Appendix 1 – Table. 1: Tiers 1 and 2 descriptions with associated categories and codes ............... 23 Appendix 2 – Grade Maps................................................................................................................. 28 Appendix 3 – Source Type Maps ...................................................................................................... 46 Appendix 4 – Field Data Sheet / Land Use Codes ........................................................................... 58 Bristol and Avon Rivers Trust 2 June 2014 Somerset Frome Catchment Walkover Report Ahern Ecology Ltd Executive Summary In 2014, Ahern Ecology Ltd. was commissioned by Bristol and Avon Rivers Trust (BART) to undertake a Catchment Walkover Survey of the Somerset Frome. The purpose of the survey was to utilise a catchment-scale methodology to simultaneously identify and classify diffuse and point inputs of phosphates, ammonia, other pollutants in addition to barriers to fish migration within the waterbody, between Rode and Witham Friary. The 3-day catchment walkover survey encompassed 19km of the River Frome, assessing all active and potential issues within three Water Framework Directive (WFD) sub-waterbodies (GB109053021840, GB109053022120 and GB109053022080). The main pressures identified by the current River Basin Management Plan (RBMP), are agricultural diffuse pollution, intermittent urban discharges, abstraction and invasive non-native species. Furthermore, the current 2013 WFD ecological classification highlights that the Somerset Frome does not, at present, provide suitable conditions for fish to meet Good Ecological Status (GES). The physico-chemical quality of the Frome is generally good and macroinvertebrates are consistently classified as ‘High’. The WFD classifications indicate that excess phosphate is a persistent pressure in the upper reaches of the Frome. This is not surprising, due to the predominantly rural nature and prevalence of agricultural land uses around the area of Witham Friary, up to the outskirts of the urban conurbation of Frome. Disruption to catchment connectivity by manmade and natural barriers is indicated by the WFD classifications, resulting in ‘Moderate’ to ‘Poor’ fish status within these three reaches of the River Frome. A total of 156 sources were recorded, 3 were Grade 1, 17 were Grade 2, 83 were Grade 3 and 51 were classified as having the potential to cause an input of diffuse or point source pollution into the River Frome. Point sources were more frequent (109 sources) than diffuse sources (48). Lack of connectivity was confirmed by the catchment walkover surveys, which found that weirs were the dominant recorded issue (19 sources). Frequent examples of urban intermittent discharges from domestic and residential premises (17 sources) and transport links (11 sources) were also identified. Agricultural diffuse pollution such as run-off from over-wintering pads, poaching and pathways around farm tracks resulting in more severe Grade 2 inputs, were more commonly encountered in the upper reaches of the River Frome. The connectivity issues facing catchment and river managers on the River Frome are highly complex and potential solutions for the majority of larger scale weirs are likely to be ‘disproportionately expensive’. The feasibility of installing fish passes or removing smaller barriers to fish migration requires further detailed investigation. Although phosphate levels in the River Frome between Witham Friary and Rode are unlikely to reach GES by 2015. Participation in capital grant schemes, such as the Egford Borehole, will allow landowners to install watercourse fencing, hard bases for livestock drinkers and ram pumps (Natural England 2014). A subsequent reduction in levels of diffuse agricultural pollution arising from livestock and arable farming should be seen catchment wide as a result. Bristol and Avon Rivers Trust 3 June 2014 Somerset Frome Catchment Walkover Report Ahern Ecology Ltd 1.0 Introduction In 2014, Ahern Ecology Ltd. was commissioned by Bristol and Avon Rivers Trust (BART) to undertake a Catchment Walkover Survey of the Somerset Frome. The purpose of the survey was to utilise a catchment-scale methodology to simultaneously identify and classify diffuse and point inputs of phosphates, ammonia and other pollutants within the Somerset Frome waterbody, between Rode and Witham Friary. In addition, any barriers to fish migration identified on the main channel were assessed and classified. 1.1 Background In March 2011, the Coalition Government announced their commitment to the catchment approach for delivering sustainable, cost-effective environmental improvement schemes for the benefit of both the environment and society. At the heart of this approach is the practice of catchment scale decision- making, with stakeholders working together to deliver actions locally. Over the next four years, £92 million will be available through the Catchment Restoration Fund (CRF) to improve the health of the UK’s rivers, lakes and estuaries. In 2011/2012, £18 million of this funding was provided to the Environment Agency, Natural England, The Wildlife Trusts, The Rivers Trust, the Non-native Invasive Species Secretariat and Local Actions groups, in order to deliver projects aimed at achieving Good Status (GS) in all waterbodies under the Water Framework Directive 2000/60/EC (WFD) by 2015. The aims of the catchment approach include restoring old river courses, aiding fish migration, increasing