Glashaboy River (Glanmire/Sallybrook) Drainage Scheme

Planning/Design Phase

Works Extent

The Office of Public Works (OPW) in partnership with both Cork City and Cork County Councils have recognised the high levels of existing flood risk in the River Lee Catchment and have carried out a Catchment Flood Risk Assessment and Management (CFRAM) Study for the Lee Catchment which includes the Glashaboy River. The Draft Catchment Flood Risk Management Plan was published in February 2010, and this identified a preferred option for the alleviation of flood risk in the Glashaboy catchment.

Significant flooding occurred in June 2012 in the Glanmire/Sallybrook area.  As a result, Cork County Council, acting as Agents for the OPW commissioned Arup in association with JBA Consulting to develop a Flood Relief Scheme for Glanmire/Sallybrook. The website Glashaboy FRS - Home ( has been set up to provide information to members of the public and to keep you informed of the project's progress.

In October 2018, the Glashaboy Flood Relief Scheme was submitted by the Office of Public Works to the Minister for Public Expenditure and Reform for formal Confirmation, under the provisions of the Arterial Drainage Acts, accompanied by an Environmental Impact Assessment Report (EIAR) and Natura Impact Statement (NIS).

On 18th January 2021 the Minister for Public Expenditure and Reform, Mr. Michael McGrath T.D., in pursuance of the powers given to him by Section 7 of the Arterial Drainage Act, 1945, and of all other powers enabling him in that behalf, announced his consent to proceed with the Glashaboy River Flood Relief Scheme. The confirmation is subject to conditions as set out and agreed to by the Commissioners for Public Works in Ireland who are the sponsoring agency for the scheme which will be implemented by them and Cork City Council.

Glashaboy is the first scheme consented to by the Minister for Public Expenditure and Reform since the new rigorous review process of Arterial Drainage Regulations 2019 came into force in late 2019. The additional responsibilities of these regulations aim to provide a high level of protection of the environment and human health.

The scheme is estimated to cost in the region of €14m. The flood relief scheme will be funded from within the allocated €1 billion for flood risk management over the period 2018-2027. Provision for the cost of the scheme is included in the Office of Public Works' multi annual capital allocation.

Approximately 103 properties (78 residential and 25 commercial) will be protected by the scheme, which will provide standard protection against a flood event, with a 1% probability of occurring in any given year (more commonly known as the one in one-hundred-year flood).

The Glashaboy Scheme went to tender in 2021 but the tender competition was not concluded due to unforeseen circumstances.  However, Cork City Council will proceed to issue new Tender Documents in the coming months.  The construction period is expected to be approximately 32 months.


The key elements of the proposed works involve:

  • Replacement of  several existing culverts with either new culverts or bridges and culvert extensions;
  • Replacement of Hazelwood Shopping Centre bridge;
  • New flood relief channel and culvert at Hazelwood Avenue;
  • Replacement of existing flood defence walls and construction of new flood defence walls;
  • Construction of a new earthen flood defence embankment at Sallybrook;
  • New surface water pumping station and one foul pumping station;
  • Localised in-channel conveyance improvements at culvert/bridge structures;
  • Local channel widening, deepening, realignment and re-grading of river channel;
  • Provision of civil works such as road/footpath re-grading at several locations;
  • Protecting drainage outlets along the line of flood defence works with non-return flap valves;
  • Retaining walls;
  • Flow control structure on a millrace;
  • Removal of vegetation and trees;
  • Removal and reinstatement of boundary walls and fences;
  • Landscaping and replanting of trees on completion; and
  • Ongoing maintenance of the modified river channel.

The scheme extends over approximately 4 km of the Glashaboy River three associated millraces, and lengths of various tributaries including: appropriately 0.5 km of the Butlerstown Stream; approximately 1.8. km of Glenmore Stream (a tributary of Butlerstown Stream) and short lower reaches of various other tributaries.


Start: Tender Phase in Q4 of 2022.

Finish: Construction expected to commence in early 2023 and be finished by late 2025.

Glashaboy River (Glanmire/Sallybrook) Drainage Scheme