Fermoy Weir Remediation & Fish Bypass

Public Consultation Update (April 2021)

Following the public consultation process undertaken in November and December 2020, A summary of the submissions received as been prepared. The Public Consultation Summary report was presented to the Fermoy Municipal District of Cork Co Co on Tues 20th April and is now available to review on this website.

Having reviewed submissions, the recommended option is remediation of the weir, mill race and original fish pass and construction of a Rough Channel Pool Bypass (Option 9).

Option 9 best satisfies the project objectives of providing fish passage to comply with requirements of Habitats Directive.

Cork Co Co have accepted the recommendation that the Fermoy Weir Remediation and Fish Bypass scheme proceed on the basis of Option 9 comprising Remediation of the weir, mill race and original fish pass and construction of a Rough Channel Pool Bypass. 

Next Steps are:

  • Development of the preliminary design proposal for the rough channel pool pass (Option 9).
  • Commence environmental reports (AA & NIS) required to proposed works in River Blackwater SAC. This will include the preparation of Appropriate Assessment and Environmental Impact Assessment screening reports and a Natura Impact Statement.
  • Commence CFD modelling for recommended rough channel pool bypass option.
  • Prepare planning drawings and documentation for planning submission to An Bord Pleanála.
19011-TJOC-XX-XX-PP-C-7052_MD_Presentation_on_Public_Consultation_Process
19011-TJOC-XX-XX-PP-C-7052_MD_Presentation_on_Public_Consultation_Process

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19011-TJOC-ZZ-XX-RP-C-3712_Public_Consultation_Summary_Report_Final

Public Consultation Process – Nov – Dec 2020

Fermoy’s early 19th Century Weir is a protected structure and iconic landmark in the town. In line with the conservation objectives of the River Blackwater Special Area of Conservation (SAC), Cork County Council will seek views and opinions from the public on options for its remediation and provision for a fish bypass channel.

The Council will undertake a non-statutory public consultation on the options and measures considered for implementation of the Fermoy Weir Remediation and Fish Bypass for a period of six weeks from Friday, November 6th until Friday, December 18th 2020. This includes a two week extension.

Recent years have seen accelerated deterioration of the weir. Due to its present condition excessive velocities of water pouring through the breach is leading to significant erosion on the south bank of the River Blackwater at Mill Island. Excessive velocity can be an obstacle to the passage of some species of fish.* Following on from a feasibility study, two options for the remediation of the weir are being considered and nine for the fish passage.

Cork County Council welcomes feedback on the Fermoy Weir Remediation and Fish Bypass project and encourages members of the public to submit their feedback online via the form below, by email to feedback@fermoyweir.ie or by post to Fermoy Municipal District Offices, Fermoy Town Hall, Fermoy Co. Cork.

In the interest of public health and safety, submissions should be made online where possible, however accommodations can be made on request, to view hard copies of the options under consideration, in accordance with public health guidelines and current restrictions. Please contact the Fermoy Area Office on (025)31947 to arrange.

*The text of this sentence was revised on the 24th November 2020

Background to the Project

The background to the proposed public consultation is as follows:

  • Fermoy weir was constructed in the early 19th century but has fallen into disrepair with the rate of deterioration accelerating in recent years. Fermoy weir is a protected structure, designated as such under the Fermoy Town Development Plan.
  • Cork Co Co is obliged to protect the weir against further deterioration in its condition. Despite the presence of a fish ladder in the weir, the weir acts as a barrier to the passage of fish.
  • Remediation of the weir will result in a continuation of this barrier to fish passage on the River Blackwater contrary to the conservation objectives of the River Blackwater SAC.
  • Leaving the weir in its present condition will not achieve compliance with the conservation objectives for the River Blackwater SAC due to the excessive velocities through the breach which prevent the passage of fish. This breach has led to significant erosion on the south bank of the river at Mill Island.
  • The existing fish ladder does not satisfy criteria for accommodating the free passage of fish, contrary to the conservation objectives of the River Blackwater SAC and is not ideally situated in the weir.
  • Inland Fisheries Ireland are the body responsible for approving the design of measures for the passage of fish.
  • A feasibility study has been completed in which a range of options were considered in respect of the weir and the provision for fish passage.
  • The options considered for the remediation of the weir can be summarised as:
    • Mitigation by Design, i.e. reconstruction using original materials;
    • Mitigation by Record, i.e. record and replace with new.

Options considered for fish passage:

The information provided for each option is outlined below, describing what each option involves and what the implications for the weir and for fish passage would be if the option were pursued.

1. Do Nothing

Cover Image for Option 1
  • Leave existing situation as is
  • Weir will continue to deteriorate
  • Complete collapse will eventually allow fish migration
  • Bank and bed erosion could undermine flood defences

2. Stabilise remaining section of weir

Cover Image for Option 2
  • Leave existing breach in place
  • Upstream river level would not return to pre-breach levels
  • Excessive velocities in mill race channel causing bed and bank erosion
  • Passage of all fish species not ensured

3. Remediate the existing fish pass.

Cover Image for Option 3
  • Not ideally located at upstream end of weir
  • Does not provide satisfactory fish passage
  • Therefore does not satisfy Conservation objectives
  • Acceptable for Protected Structure Status
  • Maintains upstream river levels

4. Complete removal of the weir

Cover Image for Option 4
  • Provides for free passage of fish
  • Lower river levels U/S of Bridge
  • Protected structure status breached
  • River amenities affected, e.g. rowing
  • Potential issues for Flood defence structures if bed levels are lower

5. Construct an in-river rock ramp.

Cover Image for Option 5
  • Provides satisfactory passage for all fish
  • Requires removal of part of protected structure
  • Extends upstream in main channel of river affecting amenity uses
  • Visual impact alongside bridge
  • Potential scour impact on bridge piers

6. Construct a fish ramp (rock ramp) in the existing breach

Cover Image for Option 6
  • Ramp not ideally located to attract fish
  • May be issues with excessive velocities
  • May conflict with flood defence structural design
  • Protected Structure obligations not fully complied with

7. Construct a near natural bypass channel.

Cover Image for Option 7
  • Reduces in-stream works
  • Land acquisition required
  • May not facilitate passage of all fish
  • Avoids negative visual impacts

8. Bypass river around weir

Cover Image for Option 8
  • Large flow to be accommodated in Bypass channel
  • Fish Passage accommodated
  • Upstream Water Levels lowered
  • Adverse impacts on Conservation objectives
  • Large land Acquisition  required

9. Construct a rough channel pool bypass.

Cover Image for Option 9
3D render of rough channel pool bypass
  • Maintains Upstream Water level
  • Facilitates fish passage
  • Minimises instream works
  • Land acquisition required
  • Significant visual impact

Before commencing preparation of the planning application and associated environmental studies and assessments for a scheme to provide for the remediation of Fermoy Weir along with the provision of a fish Bypass channel at Fermoy the views and opinions of the public and relevant stakeholders are invited.

Full Presentation

Here you can view the full presentation submitted to the municipal district councillor, September 2019

You can view the PDF presentation in a new tab here –

You can view the full Options Report here –

Comment & Feedback

Cork County Council welcomes feedback on the Fermoy Weir Remediation and Fish Bypass project and encourages members of the public to submit their feedback online via the form below , by email to feedback@fermoyweir.ie or by post to Fermoy Municipal District Offices, Fermoy Town Hall, Fermoy Co. Cork.