Emigration as a result of both hurricane Hugo in 1989 and the onset of volcanic activity in 1995 has Erastin manufacturer reduced Montserrat’s population to 4500, easing pressures on the water supplies. The current demand of ∼14 ML/week is met by production from six springs on flanks of the extinct volcanic centre of Centre Hills. In 2012 supply from these springs averaged

35 ML/week; excess discharge flows down the ghauts and percolates through the beds of the losing stream. Consumption rates are expected to rise as population and agriculture continue to recover during periods of reduced volcanic activity. While current spring yields provide a surplus and can cope with significant increases in demand, historical variations in spring yield provide some cause for concern. Anecdotal evidence (MUL, pers. commun. 2012) suggests that spring behaviour is affected LEE011 ic50 by volcanic activity. Spring production data suggests that yield declined significantly in the 18 months prior to the onset of the eruption and remained low for ten years. In the early 2000s, during a prolonged period of activity (Phase 2, Fig. 15), spring production declined to levels below the current consumption rate, reaching

yields less than 12 ML/week in 2003. Low yield behaviour ended abruptly at the end of 2004, with a sudden production increase to over 25 ML/week (Fig. 15). However, as the spring production data reflects natural recharge fluctuations as well as infrastructure disruptions, establishing a causal link between volcanic activity and spring yield is difficult. Spring yield fluctuations highlight the fragility Low-density-lipoprotein receptor kinase of this essential resource and underline the need to understand the controls on Montserrat’s hydrological system. Volcanic activity has buried the spring on SHV. Currently, all of the island’s freshwater

is supplied by six springs on CH. There are also a number of untapped springs on CH. Previous studies (Chiodini et al., 1996, Davies and Peart, 2003 and Jones et al., 2010) have suggested uniformity in temperature and composition of the CH springs. However, measurements of temperature and specific electrical conductivity (SEC) during field campaigns in February and November 2011 and February 2013 indicate differences between CH springs that merit further attention. The majority of springs on CH, particularly the western and northern springs, discharge water at 22–24 °C and 281–353 μS/cm (Table 3). However, a number of springs on CH produce water above 25 °C. These warmer springs lie in a north-east linear trend and include the high yielding (19 L/s) and high elevation (297 m amsl) supply spring of Killiekrankie (Kk) (at 25.9 °C), on the southern flank of CH, and the low yield (0.01 L/s) and relatively low elevation (190 m amsl) Bessy Mack (BM) (at 25.4 °C) towards the island’s east coast (Fig. 16). The highest temperature recorded is at the previously unreported low yielding (∼0.8 L/s) Fairy Walk (FW) where spring waters approach 29 °C.