Allan Water Barrier Easement Project Phase 1
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F u n d e d b y On behalf of REPORT Allan Water Barrier Easement Project Phase 1 Technical assessment of structures and identification of next steps Client: River Forth Fisheries Trust Reference: IEMPB4892R001D01 Revision: 02/Final Date: 12 April 2016 O p e n HASKONINGDHV UK LTD. 36 Park Row Leeds LS1 5JL Industry & Buildings VAT registration number: 792428892 +44 113 360 0533 T royalhaskoningdhv.com W Document title: Allan Water Barrier Easement Project Phase 1 Document short title: Allan Water Barrier Easement Project Phase 1 Reference: IEMPB4892R001D01 Revision: 02/Final Date: 12 April 2016 Project name: Allan Water Barrier Easement Project Phase 1 Project number: PB4892 Author(s): Clare Rodgers, Ian Dennis, James Davill and Alan Kettle-White Drafted by: Clare Rodgers Checked by: Ian Dennis Date / initials: 12/04/16 IAD Approved by: Ian Dennis Date / initials: 12/04/16 IAD Classification Open Disclaimer No part of thesethese specifications/printedspecifications/printed mattermatter may may be be reproduced reproduced and/or and/or published published by by print, print, photocopy, photocopy, microfilm microfilm or or by byany any other other means, means, without without the priorthe prior written written permission permission of HaskoningDHV of HaskoningDHV UK Ltd.; UK norLtd. may or ourthey client be used,; nor withoutmay they such be used,permission, without for such any purposespermission, other for thanany purposesthat for which other they than were that produced. for which HaskoningDHVthey were produced. 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HaskoningDHV accepts no UK Ltd.responsibility accepts no or responsibilityliability for these or liabilityspecifications/printed for these specifications/printed matter to any party matter other to than any thepar typersons other thanby whom the persons it was by whomcommissioned it was andcommissioned as concluded and under as thatconcluded Appointment. under Thethat quality Appointment. management The systemquality ofmanagement HaskoningDHV system UK Ltd.of HaskoningDHVhas been certified UK in Ltd. accordance has been with certified ISO 9001,in accordance ISO 14001 with and ISO OHSAS 9001, ISO18001. 14001 and OHSAS 18001. 12 April 2016 ALLAN WATER BARRIER EASEMENT PROJECT PHASE IEMPB4892R001D01 i 1 O p e n Table of Contents 1 Introduction 1 1.1 Background to report 1 1.2 Species impacted 1 1.3 WFD, ecology and hydro- and geomorphology justification 1 1.4 Aims and objectives 2 2 Task 1 Method 4 2.1 Site description 4 2.2 Structure assessment and surveys 6 2.3 Approach to determining options 9 3 Task 1 Results 11 3.1 Introduction 11 3.2 Danny Weir 11 3.3 Buttergask Weir 12 3.4 Lower Rhynds Dam 13 3.5 Millstone Weir 14 3.6 Greenloaning A9 Culverts 16 3.7 Feddal Abstraction 17 3.8 Feddal Dam 18 3.9 Wester Cambushinnie Dam 19 3.10 Auchinlay Culvert 20 3.11 Scouring Burn Sediment Retention Wall 21 3.12 Muckle Weir 23 4 Task 2 Method 25 4.1 Site locations and rationale for targeting the reach 25 4.2 Targeted walkover survey 25 4.3 Level of assessment used 25 5 Task 2 Results 27 5.1 Desk study of additional significant pressures 27 5.2 Targeted walkover survey 29 5.3 Review of salmon presence and habitat survey results 35 12 April 2016 ALLAN WATER BARRIER EASEMENT PROJECT PHASE IEMPB4892R001D01 ii 1 O p e n 6 Discussion: Catchment Plan 39 6.1 Catchment scale planning considerations 39 6.2 Catchment scale prioritisation 40 6.3 Prioritisation of Task 1 and Task 2 barriers 41 6.4 Factors limiting response to mitigation 46 7 Conclusions and Recommendations 48 8 Appendices (attached separately) 8.1 Appendix 1: Blank Task 1 Survey Sheet 8.2 Appendix 2: Completed Task 1 Survey Sheets 8.3 Appendix 3: Verification of Ownership Table for Task 1 8.4 Appendix 4: Blank Task 2 Survey Sheet 8.5 Appendix 5: Habitat data from RFFT and AWAIA 2016 12 April 2016 ALLAN WATER BARRIER EASEMENT PROJECT PHASE IEMPB4892R001D01 iii 1 O p e n 1 Introduction 1.1 Background to report The River Forth Fisheries Trust (RFFT) and the Alan Water Angling Improvement Association (AWAIA) are working together to address the issues caused by barriers, such as weirs, throughout the Allan Water catchment near Dunblane in Scotland. Based on SEPA data, ten of the barriers in this catchment may be eligible for WEF funding. These barriers are contributing to a downgrade in ecological status of the water body. The RFFT has added a further priority barrier (Muckle Weir) to this list due to its likely impact on fish migration. Figure 1.1: Barriers range from weirs to reservoir outflows and culverts The aim of this project is to assess these eleven barriers, consider the mitigation options available to restore fish passage at each and review the impact of additional features in the Allan Water catchment that might limit the effectiveness of mitigation measures for restoring fish passage in these rivers. 1.2 Species impacted The water bodies of the Allan Water catchment are failing to meet Scotland’s targets under the Water Framework Directive (WFD) of Good Ecological Status / Potential. One of the main areas in which the Allan Water water bodies are failing is in terms of the biological quality elements, specifically free movement of fish up and down the catchment. The passage of migratory fish including sea trout Salmo trutta and Atlantic salmon Salmo salar has been considered at each site through the course of this project. In addition to this, the passage of other native migratory fish species including resident brown trout Salmo trutta, European eel Anguilla anguilla and lamprey Petromyzonidae / Lampetra spp has also been given consideration, in line with the requirements of the WFD. 1.3 WFD, ecology and hydro- and geomorphology justification The mainstem Allan Water and its tributaries have a number of barriers along their length, associated with a range of uses and features including recreational fishing, road culverts and water supply. These barriers operate both individually and collectively at the catchment scale to inhibit the passage of migratory fish and prevent the transfer of sediments through the system. SEPA has an obligation to deliver Good Ecological Status (or Potential) by 2027 in all Scottish water bodies including rivers, lakes, groundwaters and estuaries as part of the European Water Framework Directive (2000/60/EC) (WFD). The main water bodies in the Allan Water catchment as far downstream as Dunblane are: Allan Water (Source to Greenloaning), water body ID 4601 – incorporating Danny Burn, Buttergask Burn and the Burn of Ogilvie. 12 April 2016 ALLAN WATER BARRIER EASEMENT PROJECT PHASE IEMPB4892R001D01 1 1 O p e n Allan Water (Greenloaning to Dunblane), water body ID 6833 – incorporating Millstone Burn, Feddal Burn, Park Burn, Auchinlay Burn and Scouring Burn. Orchill Burn, water body ID 4607 – incorporating Rhynd Burn. Muckle Burn, water body ID 4604. Lodge Burn, water body ID 4603. Bullie Burn, water body ID 4605. River Knaik, water body ID 4606. Many of these water bodies are failing to meet the required classification, and barriers to fish passage are one of the main causes for this failure. SEPA has therefore identified a need for habitat improvements and removal of barriers or provision of mechanisms to enable fish migration for the water bodies in this catchment. Eleven impassable barriers have been identified by SEPA and the RFFT in the Allan Water catchment and subsequently prioritised for mitigation through SEPA’s Water Environment Fund (WEF). This report provides RFFT with a technical assessment of these structures and others which are likely to be significant in this catchment, to determine the appropriate next steps to improve the passage of fish beyond the structures identified. Whilst the focus of this work is on fish passage, this project recognises that the overall impact of these structures extends beyond fish migration. Measures to remove or mitigate these structures can bring a range of benefits to the health and resilience of the catchment as a whole through restoration of natural hydrological, geomorphological and ecological processes, and these factors have therefore also been considered in the identification of appropriate options for each site. 1.4 Aims and objectives The overall aim of this project for the RFFT is to facilitate fish passage for migratory species and increase habitat utilisation across the Allan Water catchment. The barriers have been considered both individually and also on a catchment scale, to ensure that the best options are proposed for each location and the catchment as a whole. This project is the initial step in the design and implementation of measures to facilitate passage for all native migratory fish beyond current barriers and increase habitat utilisation across the Allan Water catchment. This report will therefore provide a sound basis for the next stages, such as detailed options appraisal, outline/ detailed design, and construction. This report presents the findings of this independent expert-led technical assessment for Allan Water and recommends a key next steps for each of the eleven barriers (as well as other barriers which are identified as being significant) to support the next phase of work on the Allan Water Barrier Easement Project. This study builds on work undertaken to date by RFFT and the Allan Water Angling Improvement Association (AWAIA) to survey the habitat and monitor fish populations in the Allan Water catchment, and carry out initial discussions with landowners and other key stakeholders. The bulk of this work (and hence this report) is broken by two main tasks: an assessment of the eleven individual structures already identified by the RFFT and SEPA (Task 1), and a catchment-scale appraisal, including surveys of additional structures and prioritisation of barrier easement works across the catchment (Task 2).