Reconnecting rivers in urban areas; challenges and considerations

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Polly McDaniel
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1 River Forth Fisheries Trust Reconnecting rivers in urban areas; challenges and considerations RAFTS-ASFB conference 2016

3 Currently five morphology project sites in the Forth District with three informing this talk: Dalkeith Weir Montague Bridge Weir Bathgate Watercourse

4 Large weir with head of 3m. Bed scour below has increased height. Crude baulk fish pass with lip at top pass is ineffective. Located immediately upstream of A road bridge. On the grounds of old mill house. Houses upstream and downstream. Design option removal.

5 Getmapping 2016

Large weir with head of over 2m, with drop to river bed of 4m. No fish passage and has prevented passage since 1793.

6 Large weir with head of over 2m, with drop to river bed of 4m. No fish passage and has prevented passage since Located in Dalkeith park within the town. No immediate housing or civil infrastructure risk. Category A listed building as part of bridge structure. Design option fish pass.

7 Getmapping 2016

8 1.4km of channel. Realigned, resectioned and choked with macrophytes. Floodplain disconnection. Houses, large store, risk of contaminated land, school, graveyard and playing pitches all present. WB failure for WFD. Getmapping, Crown Copyright and RFFT, 2016

9 Who pays? Bathgate - WFD downgrade, deprived location, potential for flood storage. o Range of (potential) funders (SEPA, HLF, LG, CSGN) Dalkeith and Montague WFD downgrade, structures owned by large landowners, but no economic value. o SEPA only, with provision of management money But all multiphase, multiyear projects requiring significant funding and commitment. And main funder difficulties with multi-year projects within phased approach.

10 Phase 1 - Scoping Phase 2 - Design Phase 3 - Build Approach High level Catchment scale Data poor Site scale Data intensive Multidisciplinary Site scale Highly regulated Strict contract Less expensive Guidance Subject to change Expensive Definitive Risky Very expensive Riskiest Final

11 1. Validation visit 3. Land ownership and use Surveys 2. Utilities 4. Terrestrial ecology 5. Aquatic ecology 6. Geological 7. Geomorphology 8. Flood risk 10. Topography 9. Vegetation surveys 11. Sediment grades 12. Sediment composition 13. Structural surveys 14. Instream habitats 15. Contaminated land 16. ECI 17. INNS

12 Licenses/planning/pre-build 1. CAR license of works 2. CAR license of remaining structure 3. EIA screening and process 4. Planning permission pre-app 6. Planning surveys 8. Conservation area consent 5. Planning permission 7. Heritage statement 9. Ecology mitigation

13 Designs and plans Outputs to end Phase 2 But also: Costings and Bill of Quantities for funding and tendering. Planning and licensing for builds/demolitions. Supporting documents (Site access statements, INNS statements, project timelines, mitigation plans...).

14 What were the issues? Many events happened that required compensation events. Mostly foreseen but ; GI had to be commissioned directly Ecological mitigation crossed funder s end of year boundary so was unfunded projects pushed back one year Assumptions based on scoping incorrect Contractual inconsistencies across tenderers Changes to yearly funding arrangements Extraordinarily high costs of contaminated land mitigation. Do we need a new approach?

15 New approach Two phases Detailed Scoping and Design & Build. Phase 1 Site based approach determined by Trust/Board/SEPA. Initial surveys to identify preferred options. Technical surveys (GI, topography, ecology, hydrology) undertaken by consultant to identify show stoppers. Initial design concept produced with estimated build costs. Planning process initiated. Phase 2 Detailed design to support build and planning, mitigation undertaken, contractor appointed and works initiated. Single agency delivery of both phases. Cheaper, quicker, identifies risks earlier, and more deliverable but requires an initial commitment in principle from all parties within a fixed, multi-year framework with clear responsibilities.

16 Otherwise.

17 Thanks to: SEPA Water Environment Fund Midlothian Council West Lothian Council Heritage Lottery Fund Royal Haskoning DHV JBA Consulting

Flood map for the existing situation

Flood map for the existing situation Flood map after completion construction of the Raciborz reservoir and the WFS modernization WFS tasks: Task no. 1. Enhancement of the Flood Canal Task no. 4. Enhancement