The Marine Section and Storm Water Control Unit of the Ministry for Resources and Rural Affairs have sent in a report to MEPA for the proposed development of coastal defences against wave incidence on shore for Marsalforn Bay including: beach nourishment; construction of groin; upgrade of storm water channel and construction of submerged breakwater, at Marsalforn Bay.

This report is being compiled to form a pre-application document in order that MEPA officials may form a conversant assessment of the proposed development and determine if further studies are required.

The report states “that the proposed interventions are located in the Marsalforn Bay, which is a natural creek and fishing harbour. For centuries this village has been functioning as a touristic venue at the same time as fishermen’s village.

The interventions will be carried out in the inner part of the said bay. They are intended to attenuate the wave heights before waves strike the foreshore.In fact the destruction of the breakwater arm at Marsalforn by recent storms has left the foreshore in Marsalforn Bay exposed to the high waves during North West to North East storms. During a 1:50 year storm the near shore North West significant wave height inside the bay and along the said foreshore is approximately 1.5m to 2.00m high .On reflection against the foreshore the formation of standing waves reach 4m height and will over top the promenade where this is just 2.6m above mean sea level.

The resulting green seas besides being dangerous for life and limb could have devastating effect on the buildings along this front and the coastal structures could also be at risk.

Mathematical Wave studies have been conducted at Sogreah Consultants in Grenoble France in order to either establish the length of the replacement breakwater arm, or any other alternative structure required to break the waves at the same time allowing the necessary water changes, and circulation. The same consultants were also given the task to check the stability of a nourished beach along the southern littoral.

Scope of Works

The entrance to this bay faces North and therefore it is exposed to North West, North and North Easterly waves. The offshore waves are refracted near shore and enter the bay along its central axis making futile any attempts to stop them by means of a breakwater arm on either side of the Bay.

Conclusion of Studies

Several Optional Locations for breakwaters within Marsalforn Bay were tested for breaking waves from a 1:50 year storm before these reach the inner foreshore.

Renourished Beach

A renourished beach was also tested in its double capacity as a wave breaking structure as well as an improved amenity in the popular summer resort..

The proposed works would be carried out over the following timeline:

May to August 2012 Dredging and formation of groin consisting of gravel wrapped up in geogrid on the West side of the bay as well as the cill in front of the storm water canal.

May to August 2012 Supply of sand and placing by means of tipper trucks spreading out by long arm back hoe.

May to August 2013 Dredging and formation of submerged breakwater consisting of gravel wrapped up with geogrid.

The sequence shown above aims first to create a groin and a cill to the existing canal in order to protect the beach nourishment slope on the West and as an anti scouring measure at the storm water discharge point into the sea followed up by the filling of the slope at the required gradient. This will enable waves entering the bay to break on the said beach and to have their energy dissipated.

The second part is the formation of submerged breakwater.

Loss of Marine Habitat During Construction

Loss of habitat underneath the footprint of the submerged breakwater, groin and canal cill is unavoidable. From the existing aerial photos there is a good indication that in the area there is very limited posedonia. Once the proposed structures are in place they will provide extra crevices and holes in which marine habitats can thrive. The proposed construction can be considered as an artificial reef where species can prosper.”

For the full report and graphics please click here.

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