Still a long way to go
The MAP surface water monitoring network is located in smaller watercourses where agriculture is the determining factor in water contamination. Because the leaching of nitrates from agricultural soils into the surface water occurs mostly in the winter, the results are presented for each winter-year (July-June).
The average nitrate concentration and the percentage of measurement points where a standard is exceeded follow a reasonable parallel trend. The decrease between 2000-2001 and 2002-2003 is partly the result of the tightening of manure policy from 2000 with stricter fertilisation standards and a reduction of the number of livestock. Between 2003-2004 and 2007-2008 little changed. Since then there has once more been an improvement in the situation. In the winter-year 2010-2011, 72% of the measurement points in agricultural areas complied with the nitrate standard. The standard specifies 50mg nitrate per litre as the maximum per measurement point. The target of 100% in 2010 specified in the MINA plan 3+ (2008-2010) was therefore not achieved. To reach the target of 84% in 2014 as specified in the MINA plan 4 (2011-2015), the improvement that has taken place since 2006-2007 absolutely must continue at the same pace in the years to come. The ambition is to increase that percentage to more than 95% before 2018.
Improvement at 30% of the measurement points
From a statistical trend analysis at each measurement point it appears that there is no significant trend in the nitrate concentration at approximately 65% of the measurement points in the period 1999-2011, 30% of the measurement points showed a significant decreasing trend and 5% a significant increasing trend. This analysis thus shows an improvement in far from all measurement points.
Farmers can reduce the nitrate losses further by using less manure and applying it better, but also, for example, by sowing a green cover crop in winter and creating buffer strips alongside watercourses.