Sunday, 12 January 2014

The new fish pass!


Photo 01 - In great condition!
 
The new fish pass!

At last we have received the proposals and timetable for the works to take place as part of the Selkirk Flood Protection Scheme and of most interest to us the new fish pass. It has long been suspected that the fish pass that is currently in place restricts the movement of fish particularly in low water conditions. Certainly i have on many occasions noted numerous fish entering the loch via the regulator and in low water conditions many fish trapped in the various pools in the steps of the fish pass! Allowing fish to enter and leave the loch more freely can only be of benefit to our stocks in the loch.  It should also be noted that if the new fish pass is found to be detrimental to Eel movement a specific Eel pass will be constructed. It is vital that this species is supported as they are currently under severe threat on a Europe wide basis! Indeed at the lochs our population must have suffered in light of the poaching that has come to our attention. Below are the proposals and timescale for the works to be carried out.

Selkirk Flood Protection Scheme St Mary’s Loch Working Group Number 5 – Briefing Note 8th January 2014


Aims of this Briefing Note

1. Review all previous work and consultation

2. Identify recent improvements to the hydraulic model and the positive impacts on flow control

3. Identify how the existing fish pass needs to be modified to implement these flow control improvements

4. Identify the costs associated with the design and implementation of the fish pass improvements

5. Summarise the actions which still require to be undertaken

REVIEW OF PREVIOUS WORK

Previous Work – SMLWG

1. The St Mary’s Loch Working Group met on four separate occasions between 2010 and 2012 to advance proposals for flood storage at SML

2. The Working Group consisted of representatives from Scottish Water, Scottish Environment Protection Agency, Scottish Natural Heritage, The River Tweed Commission, Scottish Borders Council and CH2M Hill (Halcrow)

3. The final output from the SMLWG process at SMLWG no #4 ratified the basic flood storage /drought management proposals (July 2011)

4. The St Mary’s Loch Feasibility Study document was the product of the SMLWG process and was included as supporting documentation in the formal Scheme confirmation and CAR licence application

Previous Work – SML Feasibility Study

1. The key proposals and outcomes arising from the Feasibility Study were:

a) Increase the flood storage capacity of St Mary’s Loch by approx. 1.57 million cubic metres

b) Achieve flood storage increase through active control of the existing gates to keep mean loch levels 390mm lower than currently, plus raise the spill level of the loch by 250mm.

c) Incremental reduction in minimum compensation flows into Yarrow Water, based on level in the loch; reducing from “normal” comp flow of 89 Ml/d to 65 Ml/d, then to 41 Ml/d during exceptionally dry conditions. Proposed that gate positions are altered automatically in response to loch level and downstream flow conditions during Normal conditions.

d) Manual intervention required to move to Flood or Drought modes of operation.

e) The net effect on flood flows is to reduce the 1 in 2 year flow rate by up to 30% and reduce the 1 in 200 year flow rate by up to 7%. The reduction in flows during the 1 in 200 year event offsets the increase in levels downstream of Selkirk as a result of implementing the defences

f) During the proposed regime, the loch level associated with the 1 in 200 year plus climate change event will be 250mm higher than during the current regime.

g) The SMLFS proposals were also shown to have benefits during very dry conditions, such that water stocks could be preserved for longer with the lower proposed compensation flows.

h) Some minor works were included in the Scheme to amend the fish pass, such that flow conditions through the fish pass during the proposed regime are no worse than during the current regime.

Previous Work – Technical Variation to CAR Licence

1. The control of flows exiting St Mary’s Loch is covered by an existing CAR Licence ref CAR/L/1014229. Scottish Water are the responsible authority in relation to the conditions contained in the licence, which relate to flow from and level within the loch.

2. The proposed changes to flow control and levels within SML resulted in the need to apply for a Technical Variation to the original licence. This was submitted to SEPA on 5th December 2011.

3. Subsequent Requests for Information from SEPA related to a range potential geomorphological, hydraulic, ecological and hydro-geological impacts, including fish ecology and passage.

4. SEPA raised concerns that although the proposed alterations to the fish pass would allow water to flow more frequently over the weirs, the depth and volume of flow could be insufficient to sustain satisfactory fish passage.

5. In September 2013, SEPA identified that the current fish passage arrangement and proposed notch cut out in the top weir (included in the Scheme to ensure fish passage is not made any worse) were not satisfactory, and further efforts would be required to achieve more desirable flow depths and velocities

Previous Work – Operational Responsibilities

1. The SMLWG originally anticipated that the various roles and responsibilities associated with the SML FS option would be shared.

2. Scottish Borders Council would construct the works and ultimately be responsible for decisions to change the gate position from Normal to Wet or Dry Mode, but all such decisions would require input from SW, SEPA and SBC representatives forming an Operational Control Team (OCT).

3. Scottish Water would continue to maintain the equipment and continue to be the responsible authority on the CAR licence.

4. With time, an alternative approach was suggested, whereby all control over operation and maintenance of the SML outlet would become the sole responsibility of Scottish Borders Council.

5. This has subsequently evolved into a proposed situation where:

a) Scottish Borders acquire all the land owned by Scottish Water at SML, with the exception of the mobile telecoms mast and pumping station on the north shore

b) Scottish Borders Council will become the responsible authority on the revised CAR licence and also be responsible for the upkeep of the structure under the Reservoirs Act

c) There is no requirement for an OCT REVIEW OF HYDRAULIC MODEL

Hydraulic Model review (1)

1. In the increasingly likely event that SBC take control of responsibility for flows and levels at SML (plus all O&M needs), a full review of the hydraulic modelling was necessary to resolve the fish passage complexities.

2. Through careful testing of the hydraulic effects of introducing a series of notches into the existing fish pass, it became apparent that around 75% of the required flows could be passed through the fish pass without requiring operation of the gates.

3. The model identifies that gate operation is only necessary during wet periods when the net inflow to the loch exceeds the capacity of the fish pass, and during very dry periods when the weirs alone are unable to discharge the minimum compensation flow.

Hydraulic Model review (2)

1. Note that HYSIM hydrology represents a much drier regime than data received from Henderland gauge

2. Optimising the spillway length improves the flood attenuation characteristics and reduces the flood levels further at Lindean.

3. All compensation flows routed through the fish pass, ranging from Normal (1030 l/s) to Drought (475 l/s) – this flow range is ideal for salmonid passage

4. Note that flow regime through the notches is streaming, rather than plunging, thus reducing the impedance to fish passage.

5. Gate operation could be simply and automatically controlled by loch level monitoring (with manual override)

6. Propose that all flow measurement (for comp flow purposes) continues at Craig Douglas

PROPOSED FISH PASS MODIFICATIONS

Fish Pass Modifications (1)

Weir 1: Remove upper weir entirely Weir 2: 0.6m deep x 3.6m wide trapezoidal notch Weir 3: 0.55m deep x 3.5m wide trapezoidal notch Weir 4: 0.33m deep x 3.2m wide trapezoidal notch Weir 5: 0.24m deep x 2.1m wide trapezoidal notch Raise spillway and side walls by 0.25m

Possibility of introducing eel pass if main flow route is not conducive to eel passage Introduce rip rap and boulders to better replicate upland fast flowing watercourse – add intermediate resting pools where necessary

Note that all weirs will be stainless steel plates bolted into an oversized opening to allow for fine tuning of the flows and depths if required

Fish Pass Modifications (2)

PROGRAMME AND OUTSTANDING ACTIONS

Fish Pass Implementation Programme

The activities required to meet the current implementation programme for all the proposed works at St Mary’s Loch, including the fish pass, are detailed as follows:

ACTIVITY 2014

Asset transfer complete

CAR TV conditions confirmed

Main works tender period

Main works contract award

CAR licence transfer to SBC

Works at SML begin civil works MEICA works Fish pass operational Overall SML works commissioned

Outstanding Actions

1. The following actions require to be completed to ensure that the proposed fish pass can be implemented:

a) Transfer of the assets to Scottish Borders Council and all legal requirements concluded

b) Discuss the fish pass characteristics and requirements with all stakeholders at SMLWG #5

c) Submit the remaining information to SEPA to ensure the Tech Variation can be finally processed

d) Build the Tech Variation conditions into the tender documents

e) Ensure all fish pass requirements are included in the Works Information

f) SBC apply for a standalone CAR licence to become the responsible authority for control of flows and levels

g) Standalone CAR licence is authorised by SEPA and SBC take control of the flows and levels at or prior to contract award
 
Image 01 - The proposals for the new outlet.
 
A meeting is to be held in St Mary’s Hall Cappercleuch in February (date to be confirmed) where people may air their views, remember that this fish pass will be with us for many years so it is vital that the proposals are thoroughly examined! We will be present at this meeting. The works at the loch is expected to be completed in the 4th quarter of the year..

Memberships!

Renewals and new member applications are now due. All applications should be made to our membership secretary Mr Robert Simpson 105 Halliburton Place Galashiels TD1 2JG making cheques payable to St Mary’s Angling Club enclosing an SAE. Places for new members are limited so early application offers the best chance of membership of the club.

Photo 02 - The latest piece of rubbish we collected!
 
Our loch!

It has long been held by biologists and ecologists that the health of a water may be determined by the condition of the top predator in that water. It works on the premise that if the condition of the top predator is good, then the food chain beneath them is also good. Any detrimental variation in the food chain will be reflected by the condition of the Pike (our top predator). Photo 01 above shows a wee jack caught yesterday in absolutely tip top condition confirming to us that all species in the loch are thriving in wild water conditions! Peerless!

More on the 50lb Salmon!

Noted in the local rag (the Border Telegraph) respected tackle dealer Ian Wilson takes the same view as us on the subject! Yes he has called for verified scales and suitable sling to be readily available for the accurate weighing of fish to give an accurate weight of those fish rather than the length weight charts used by many to estimate weight.

I have a 30kg set of digital weighing scales and carp sack with me on the lochside at all times and the reason for this is simple! On catching a potential specimen fish I can accurately weigh the fish and if necessary when at home make up the weight with items of known weight to check the accuracy of the scales! Yes the suspected 50lb salmon will not be recorded in history as such, simply a very good fish close to 50lbs which is a real opportunity missed to publicise this potentially significant fish had it been weighed!

The wider world in my view!

A £90.00 haircut, a lying puppet and a choice!

Yes from the man who said “we are all in it together” Lord Snooty revealed that he pays £90.00 for a haircut! A sum of money that would constitute 3 weeks of spending on food for an elderly person or single mum! Is it any wonder these posh buffoons can command no respect in the country; it is and always will be them and us! Interesting to see that Lord Snooty’s barber received an MBE, probably just coincidence!

As expected with the turn of the year Puppet Clegg is beginning to make noises serving to differentiate his group of collaborator puppets from the big bad nasty Tories! Yes after 3.5 years of indefensible collusion trying to secretly support poor punishing policy he now wants to distance himself from the Tory hatchet men. Well to Puppet Clegg and his doomed ship of lying puppets the whole country can see exactly what you are doing. Perhaps arch buffoon and Butcher Thatcher clone Boris Johnston summed it up best - the Mayor of London, who this week called the Deputy Prime Minister a “prophylactic protection device”. In other words a condom, yes lap dog of Lord Snooty, a political figure now inextricably associated with lying and betrayal, in political parlance – a “has been”!

Minister without a clue, cocaine snorting, Bullingdon boy Gideon Osborne stated this week that the coming year would require of the poor working classes an extra 25 billion pounds of savings pushing the above group of people further into poverty! There is however now a real choice at least for us Scots and that is a socially fair government in the guise of the SNP!

Yes I was further glued to this movement when Paul Wheelhouse announced plans to wrest from the few landowners who own most of Scotland their land to move it into public ownership! This is an exciting opportunity to redistribute this wealth from the few to the many! Couple this to the pledge to re nationalize the Royal Mail and others and it becomes clear that there is for us Scots a real alternative to the incessant bungling of the posh boys! An upcoming day in September will go down in history as the most important date in our history for hundreds of years!

The “recovery” continues!

Yes driving through the town last week I was disappointed to see a number of shopkeepers throwing in the towel and closing early. Doubtless worn down by the tedium of the day not being able to speak as no customers ventured near! Yes the demise of the High street continues!

An eminent professor from the Centre for Retail Research Joshua Barnfield has predicted that in the coming year 12,000 shops large and small will close for good! Insolvency firm Begbies Traynor also sounded a warning that 151 significant retailers have “critical” problems and 15,792 have “significant” problems. Yes the banking crash and latterly the Con-Dems have much to answer for and as for the recovery much heralded by Lord Snooty, don’t bank on it!

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