Consent Requirements - Construction/Alteration of Watercourse Infrastructure

The OPW seeks to maintain the existing conveyance and storage capacities of channels and floodplains. The design and construction of bridges and culverts should be such that flood risks up- and / or down-stream are not increased, or, where no other viable options exist, are restricted to acceptable levels, and should comply with any flood risk management objectives and plans established for the area.

Section 50: Arterial Drainage Act, 1945 The consent of the Commissioners is required by bodies and persons proposing to carry out construction/alteration works on bridges and culverts.

Section 9: Arterial Drainage Amendment Act, 1995 The Commissioners may consent to alterations to existing watercourses or structures in Drainage Schemes if the proposed works would not increase the risk of flooding or have a negative impact on drainage of land. This section applies to regrading or relocation of watercourses, replacement or relocation of embankments and various other works on Drainage Schemes. Applications under this section are dealt with on a case by case basis, and applications should be addressed to the appropriate OPW regional office.

Section 47: Arterial Drainage Act, 1945 Any person planning to erect or alter a weir must first get consent from the Commissioners or all the affected landowners. The Commissioners may grant consent only where the applicant meets stringent requirements. The ESB is exempt from this requirement as a separate statutory process is in place.

• Examples of Applications
• Reference Information and Technical Guidance Material for Applicants
• Hydrometric and Hydrological Data
• Reported Flood Event Data on FloodInfo.ie