Dredging of Sligo Harbour Entrance Channel


Dredging of Sligo Harbour Entrance Channel

Sligo County Council

RPS was commissioned by Sligo County Council to prepare a feasibility study and subsequently undertake an Environmental Impact Assessment (EIA) to gain the necessary consents for dredging the entrance channel to Sligo Harbour.

A feasibility study was undertaken to determine a scope for dredging the entrance channel to Sligo Harbour to an optimum depth within a constrained budget. Detailed hydrodynamic modelling was undertaken to ascertain the influence and extent of the dredging plume within Sligo Harbour. It was eventually determined that the optimum depth for the navigation channel was to dredge to -3.0m C.D. which would allow the passage of vessels up to 4,000 DWT to the quay during high water.

The proposed dredging would generate 250,000m³ of dredge spoil and RPS undertook a feasibility study to examine the alternatives for disposing of the dredge spoil in detail. The spoil was considered to be unsuitable for reuse in engineering projects or reclamation and consequently it was proposed that the material be disposed at an offshore dump site. An Environmental Impact Study was completed for submission with a Foreshore Licence and Dumping at Sea Licence application in May 2011.