The Dutch water injection dredger 'Jetsed' pictured in 2014. The vessel has returned to Cork this month for further dredging works. Pic: Richard Mills

Expect a temporary stink as river bed is dredged

EXPECT a stink from the River Lee in the coming days as the Port of Cork dredges the riverbed.

Every three years the Port of Cork carries out dredging work in the harbour and the quaysides to maintain the shipping channel. The work disturbs the riverbed, dragging up sediment and releasing gases like hydrogen sulphide. While the gases are safe, they are responsible for the eggy smell that could hang over the river in the coming days.

In 2014, Barrack Street, MacCurtain Street, Shandon, North Main Street, Patrick’s Street and Merchant’s Quay were all affected by the smell as a result of dredging. However, it was thought the lack ro rain and warm temperatures exacerbated the situation at that time.

The current dredging scheme is expected to last until the end of October but the city quays portion is planned to be completed by October 9, limiting the smell in the city centre. The Port of Cork said it is taking measures to limit the impact.

"These gasses are the result of decomposing organic matter on the seabed and under the silt. In some areas, there are still the remains of the sewage which was historically pumped untreated directly into the river prior to the commissioning of the Cork Main Drainage System."

"These areas have a more pungent odour as there are still some gasses released as a result of this historic activity. On occasion, depending on the wind direction, when the dredger is operating in these areas (particularly near the train station), this odour can be transported to areas of the city," the Port company said.

The vessel only dredges the city quays areas at high tide for a maximum of 40 minutes, twice in a 24 hour period, due to tidal restrictions, and daytime dredging is kept to a minimum where possible.