THE first water quality tests for the 2017 growing season show that levels of pesticides in untreated water are similar to those recorded last year. Oxadixyl, last used in 2003, was detected in 2016 throughout Jersey’s untreated water sources. Recent monitoring has also picked up azoxystrobin, metribuzin and glyphosate.
Testing of water continues all year round, but these are the first results since farmers started planting potatoes for the new season. It is too soon to tell if this is a one-off occurrence. However, it’s a reminder that farmers need to be vigilant as sudden rainfall can quickly wash chemicals off the ground and into water.
A body established last year to work for improved water quality – the Action for Cleaner Water Group – will continue to support a package of measures put in place to improve Island water quality, and particularly, to reduce the levels of pesticides in Island water courses during the current potato season.
Measures include an immediate ban on the sale and distribution of all plant protection products containing the active ingredient linuron. This was detected in Jersey waters, including Val de la Mare reservoir, on a number of occasions last year. New regulations are to be introduced to address land management practices that can cause water pollution. There will also be tighter controls on pesticide use in certain sensitive areas, such as Val de la Mare and Queen’s Valley and expanded areas for trials such as the use of slow-release fertiliser.
Last year, the level of oxadixyl in streams and reservoirs remained below the revised World Health Organization (WHO) advisory health limit for oxadixyl of 30 micrograms per litre (ug/l). Environmental Protection officers from the Department of the Environment have monitored the levels of oxadixyl in private water supplies and all tests show they remain well below the current advisory WHO-based health limit.