Smolt migration improvements underway at Catrine

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Smolts delayed in the Catrine intake during 2017

Good news is that the work required at Catrine to improve smolt passage is underway. The Board and ART pressed SEPA to require Catrine Community Renewables to make improvements at Catrine Dam since the scheme was commissioned and while some alterations were made, smolts were still prone to delays in 2019. The original installed bywash system was unsatisfactory and led to delays and damage to smolts.  SEPA agreed and instructed improvements to be completed in time for the 2020 smolt run.

Construction is underway to create a new bywash intake

CCR have again taken advice from a dedicated fish pass specialist who designed a new intake and bywash and are now in the process of having this new chamber, new bywash pipe and upgrade to the old bywash pipe installed. Once complete, the two bywashes will function similtanoeusly. Reassuringly, CCR are also making provision for increasing the flow through this bywash from another pipe should it ever be required giving scope for further alteration without too much disruption.

The old bywash will be reinstalled and incorporated into the new bywash pipe. Both will operate similtaneously


A larger bywash pipe will be installed to carry increased volume. This should result in this being a more attractive route than in previous years

This morning Ayrshire Rivers Trust  received concerns from supporters over the impact of draining the voes on birds but hopefully as this is just in advance of their breeding season, they won’t be disrupted too much. Balancing all wildlife requirements is difficult as breeding seasons frequently aren’t aligned.  Lamprey ammocetes (pre emergers) are known to use the voes in quite high numbers and it is hoped they will survive within the silt and sediments, particularly if they don’t dry out. Given the weather of late, they made be just fine.  Any fish and eels in the voes were hopefully washed downstream as the voes were drained but it may have been beneficial to remove perch rather than releasing them to the river as again they seem always to be present in these reservoirs although recently in low numbers.

The drained voes at Catrine. Work should be completed shortly and the voes refilled

The fact that this work is underway is recognition that ART’s and the District salmon Fishery Board’s concerns were valid and their input and influence was essential in bring about these works. It may have taken some time for all to agree that improvements were necessary but at least we are now all appear to be in agreement and moving forwards. This should positively benefit the river and fish population but we will continue to monitor the situation.

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