NRW
River Wye: programme of alternative mitigation work
Note of field visit to upper Lugg and Arrow
Date: 15th April 2015
Venue: upper Lugg and Arrow catchments
Present:
Jason Jones NRW
Stephen Marsh-Smith WUF
Tony Norman Upper Lugg & Arrow Fisheries Association
Stuart Smith WSA
Mike Timmis WSFOA
Peter Gough NRW
Apologies:
Rob Denny Monnow Rivers Association
Simon Evans WUF
Seth Johnson Marshall WUF & WSFOA
David Revill Wye LFG
Introduction
PG introduced the purpose of this visit which was an inspection of weirs on the Welsh reaches of the Lugg and Arrow. A shared view of priority of tackling these barriers compared to other mitigation activities would then be developed.
Barriers to migration
The following weirs were inspected:-
Lugg
Boultibrooke Weir (also known as Saw Mill). Number 26 (Lugg) on NRW listing
Concrete baulk constructed by WUF in September 2011.
Agreed that his facilitated salmon passage (and probably also trout), and difficulty rating lowered.
Weir still prevents passage of minor species, and is therefore not WFD compliant.
CONCLUSION – NO ACTION REQUIRED UNDER AM
Boultibrooke Bridge Weir. Number 27 (Lugg)
Weir much lower than previously assumed, at about 0.8m.
Low priority for salmon (and trout).
CONCLUSION – NO ACTION REQUIRED UNDER AM
Dolley Green Weir. Number 28 (Lugg)
Relatively high and broad weir that will clearly obstruct salmon in range of flows.
Salmon know to have reached this point, but no further, in recent years.
Recent attempt by WUF to amend weir lead to structural problems and weir was stabilised with no benefit to migration achieved.
Option identified: interim lowering of weir crest, to be followed by assessment of upstream bank stability and fish migration performance.
Subsequent weir removal may follow.
CONCLUSION – PRIORITY 1 FOR ACTION UNDER ALTERNATIVE MITIGATION PROGRAMME
Action:- Explore preferred option with landowner ACTION: WUF
Confirm any heritage listing ACTION: JJ
Confirm funding and partnership options ACTION: PG
Arrow
Llanpica Weir. Number 24 (Arrow)
Relatively low head, long diagonal stone-pitched weir. Still supporting abstraction to old fish farm.
Salmon known to have reached this area in 2014, but failed to pass weir.
Weir is difficult for migration.
Options identified: EITHER construction of half-width rock ramp, probably on LHS
OR lowering of half of weir, probably LHS
CONCLUSION – PRIORITY 1 FOR ACTION UNDER ALTERNATIVE MITIGATION PRIOGRAMME
Action: Confirm whether there is extant abstraction licence ACTION JJ note there is a confirmed extant abstraction licence here, but permitting only a 50% abstraction
Confirm any heritage listing ACTION: JJ
Open liaison with weir owner ACTION: WUF
Confirm funding and partnership options ACTION: PG
Conclusion
The group concluded that we have 2 high priority weirs for action ASA)P: Dolley Green and Llanpica.
Prioritising works
We previously agreed that we need to prioritise the top 3 in each of the main categories of work.
As a first stab:-
Work Site Approximate Cost
Barriers Dolau Green – rock ramp £30k
Llanpica – pre-barrage or removal £25k
Crucorney – rock ramp £40k
KRC Upper Ithon (JJ paper) £90k (can be spread across several years)
Other KRC sites £50k – £100k
Riparian management sites tbc £7 per metre
Instream habitat Upper Irfon £5k
Other sites tbc £5k per site
The group now agrees to prioritise the barrier works at Dolley Green and Llanpica, but to have a set of KRC sites as reserve projects.
ACTION: ALL TO PROVIDE ANY FURTHER COMMENTS ASAP
Next meeting
TBC
End
