Hydrogeothermal Conditions in Éire - Geological Survey of Ireland

- 5 -II-l. LocationThe general location of the 17 warm springs listed in Table 1 areshown on Fig. 1, while the main Leinster group (Nos. 1001 to 1010) arelocated in more detail on Fig. 2. There are rumours of other warm springswhich need to be investigated; it is anticipated that the plannedgeothermal energy investigation will reveal more such springs.The Leinster springs tend to occur along the Meath/Kildare border,as in Fig. 2. The country is open, slightly rolling, with varying depthsof persistant Quaternary cover. A noticable feature is the fact thatseveral of the springs (as Nos. 1002, 1007, 1008) occur on high ground,small rises or mounds. This is particularly remarkable in the case ofBride's River Kilcock (No. 1002) from which the stream splits and flows intwo directions. At least two of the Leinster springs were brought intoexistance by man's activities. Louisa Bridge spring, Leixlip (No. 1001)started to flow or to be identified when the Royal Canal was being constructedin 1794; it was quickly developed as a spa (Maxwell, 1974). Enfieldspring became known in the 1890s, when gravel was being excavated forrailway line construction (Davies & Hill, ]965).. The other springs appearto be long established; that at St. Germans (1007) was examined by geologistDu Noyer on 21 July, 1859, and his comments are written on the back of the6" sheet.Signi!icance is attach.ed to the fact that some of th.e warm springsissue from high ground, and to the fact that two of the larger were broughtinto existance by man's activities. Another point of possible significancefor the Leinster warm springs shown on Fig.2 is their distance apart.When plotted, their rather uniform distance apart was noticed, and whenscaled appeared to be of the order of 8 kilometres. Circles of 8 kmdiameter have accordingly been drawn ~round the 11 warm springs on Fig. 2.Could the enclosed areas (about 50 km ) be those contributing to eachindividual warm spring? Are additional warm springs more likely to befound in such gaps as those between Nos. 1009 and 1001, and between Nos.1010 and 1006?Of the Munster group of springs, those at Mallow are by far the bestknownand unique in their occurrence. Rutty (1757) gives much information.Dalton (1889) gives several references, including Jephson (1834) who statesthat in autumn/winter 1833, temperatures ranged from 67 0 F (19.33 0 C) to .71.3/16 o F (2l.77 o C) at the main Spa, while a spring 100 yards to the north~ow Lady's Well) was lOF warmer (max. 22.33 0 C). Mallow warm springs occurin a deep glen, on the edge of the town, and close to the Blackwater river.There is a Spa House. In the past decade, two boreholes drilled nearbyencountered warm water; the one at the Mart (No. 2002) is in use, the otheris closed and the warmth of its water has been queried. The two otherknown Munster springs, at Newcastle West (No. 2003) and at Hurler's Cross(No. 1004) occur in open rolling country, with no special topographicexpression, though No. 2003 is near an old rath and on slightly higher ground./ ...