Nitrate levels in groundwater bodies

What is the status of groundwater with respect to nitrates?

Nitrates in groundwater result from anthropogenic activities, mainly the application of nitrate-rich fertilisers, which leach into the aquifer system. In 2011, nitrate levels exceeded the EU limit value of 50mg/l in 11 out of 15 of groundwater bodies. In 2010 nitrates also exceeded the EU limit value in 11 out of 15 groundwater bodies.

The highest nitrate concentration (488mg/l) was again recorded at Pwales coastal groundwater body, increasing by 28.9 per cent since 2010.

The highest value in the perched aquifer was recorded at Żebbug at 213.5mg/l. Nitrate concentrations in the mean sea level aquifer systems were also high. In 2011 the mean nitrate level at the Malta mean sea level groundwater body was 64.2mg/l, down from 70.2mg/l in 2010, and indicating that the nitrate levels in this aquifer are relatively stable. The mean level recorded at the Gozo mean sea level groundwater body decreased slightly to 47.5mg/l. In line with the Water Framework Directive, Malta is bound to achieve a 50mg/l limit value for nitrates by 2015.

For more information see The Environment Report Indicators 2010-2011 at http://www.mepa.org.mt/teri2010-2011 .