County Archives - Page 2 of 2

Kerry

Drongawn Lough is a natural rock lagoon with a restricted tidal range due to a narrow connection with the sea through a small tidal bay which itself has a narrow connection to the open sea. The lake lies on the south coast of the Ring of Kerry peninsula, 6 km to the east of Sneem. Kenmare Bay lies 300 m to the south of the lake but is separated by a ridge of rock and the inlet to the lake lies in the northeast corner via Coongar Harbour. Very little appears to be known about this lake, other than the fact that a small flock of Whooper swans (Cygnus cygnus) is often present in the winter. It is, however, a good example of a completely natural, moderately large, saline lake on the mountainous Kerry coastline in an almost perfect state of preservation.

Wexford

Formerly an area of mud flat and salt marsh, reclaimed in the mid 1800s by construction of a sea wall. A broad, semicircular channel runs through polder grasslands and crops, covering a total area of approximately 5ha. The area is below high tide level and there is extensive landward seepage of seawater with seepage streams. Mixed seawater and freshwater from streams and drainage ditches is pumped out and the water level is more or less constant. A salinity gradient from about 4‰ in the west to between 20 and 30‰ in the Raven (Curracloe). Channel exists throughout the year.

Formerly a creek system in mudflats, reclaimed in mid 1800’s by construction of a sea wall. The network of creeks joining the large Coal Channel runs through an area of polders and salt marsh. Substrate near the sea wall muddy sand – sandy mud. Brackish conditions are probably confined to the part of the Coal Channel near the sea wall where landward seepage of seawater occurs, giving a salinity of 2-5‰. Elsewhere water is probably fresh. Excess water is pumped out into Wexford harbour by way of an artificial perimeter canal.

A large (350ha) natural sedimentary percolating lagoon, separated from the sea by a sand and gravel barrier and dunes. Substrate grades from soft sandy mud in the north to coarse sandy gravel near the barrier and there are rocks in the southeast. Surrounding land is flat with arable and pasture fields and rough land with rocks. Freshwater enters by a few small streams and leaves by percolation through the barrier. The water level rises in winter flooding farmland and a pilgrimage path and the barrier is usually breached in spring. The lake then becomes tidal until natural closure in 2 weeks – 6 months. Seawater also enters by seepage and overwash of the breach bar. Salinity fluctuates widely according to season and the extent of tidal flow. In October 1996, 4-15‰ was measured at the north end, 23-26‰ near the barrier and 6-10‰ in an isolated pool.

Large (430ha) natural sedimentary lagoon with a sand/shingle barrier. In total area this is the largest Irish lagoon but is currently drained and partly dry in summer. A natural outlet has existed intermittently but seals naturally. The substrate is soft sandy mud with gravel near the barrier. Surrounding land is flat and consists of arable fields and pasture. Freshwater enters by several small streams and leaves by the outlet pipes and by seaward percolation through the barrier. Washover occurs in the western sector. Much of the lake bed was exposed during the summer of 1996 following installation of pipes, but water was present to 1m depth by October. Salinity at this time was 8-19‰ on the eastern shore and 3-18‰ in artificial channels near the barrier. Water levels have been monitored recently in an attempt to establish optimum acceptable levels in order to preserve its conservation value.

Ballyteige drainage channels are situated on the south coast of Wexford, 1 km to the west of Kilmore Quay. The drainage channels are artificial and were excavated to drain a lagoon and saltmarsh which were isolated behind an extensive dune system to the south and a sea wall to the west, constructed across the Cull Inlet in the mid 19th Century. Seawater enters by percolation through the dunes along the southern shore and apparently by leakage of the sluice on the Cull at high tide. It is also possible that seawater enters from the tidal river that runs from Duncormick to Bridgetown. Area of water about 5 ha., length of channels 3.2 km., maximum depth 3m.

Wicklow

Louth

Dublin

Cork

Bessborough Pond is located within the grounds of The Sacred Heart Convent, Blackrock, 4.5 kilometres to the south east of Cork City. The area covers just over 135 m² and lies at an average altitude of 9 metres above mean sea level. A very small (1ha) artificial lagoon apparently formed as part of an ornamental garden with five small islands. Hydrology of the pond may have been modified by construction of the new bypass south of Cork City. The pond is now largely stagnant but still receiving saline water through a pipe, and salinity measured 23.7psu at the time of sampling on 27/7/06.

Kilkeran Lake is a small (16ha), shallow (<3m) natural lagoon, lying behind sand hills on the south coast of Co. Cork , about 5 km east of the town of Rosscarbery and 2 km north of Galley Head. A channel leads from the lagoon 400 m to the shoreline where the water of the lake is impounded for most of the year by a short, coarse sand barrier, which the County Council periodically breach, but that also opens naturally, when water levels rise. The barrier closes again naturally, generally within a few weeks. Salinity is generally low, and measured 1-2psu when sampled in 1996.The lake has suffered from extreme eutrophication, and the once thriving trout fishery has now gone.

Lissagriffin Lake is situated at the western end of the Mizen peninsula, 5 km west of Crookhaven. The lake lies at the landward end of a long sinuous tidal inlet and is partly artificial in that it now lies behind a causeway, but at the mouth of the inlet is a dune barrier through which the combined action of river and sea has cut a channel. The lake is very shallow (<2m) and seawater enters on all tides but a relatively large amount of fresh water also flows through the lake. Salinity at the time of sampling (29-31/7/96) ranged from 6-28psu.

Kilmore Lake is a natural sedimentary lagoon with a low cobble barrier. The lagoon is situated on the west coast of Whiddy Island, Bantry Bay, approximately 2 km to the west of the harbour. Seawater enters by percolation and by overflowing the low central part of the barrier, even on high water neap tides. The lagoon is small (c. 6 ha) and shallow (up to 3m) and with regular tidal flushing, salinity remains close to that of seawater, probably throughout the year, although 26 ppt was recorded near the barrier on 8/7/98 and salinity is always slightly lower at the northeast end where a small stream enters. Most of the central part of the lake consists of fine, muddy sand sediments with very little fauna.

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