Water Framework Directive a threat to crop protection
As the quest for improved water quality progresses, Teresa Rush examines the likely effects on arable farms.
It is not just the revision of EU pesticide legislation that is likely to result in large-scale losses of pesticide ingredients and the need for changes in farming practice.
The implementation of water quality legislation in the form of the Water Framework Directive (WFD) is also set to impact on the availability of a number of active substances and the effects could be felt sooner rather than later on UK farms and go beyond those expected as a result of the revision of 91/414.
The Water Framework Directive (2000/60/EEC) established a water policy framework for the European Union. In England and Wales implementing legislation came into force in January 2004, requiring all rivers, lakes, coastal and ground waters to reach good ecological and chemical status by 2015. The WFD was transposed into Scottish law through the Water Environment and Water Services (Scotland) Act 2003.
Farming and water advisers are warning the active substances which are most likely to be affected by the WFD are those used on large areas and/or at high rates. In the UK this makes herbicides particularly vulnerable, says James Clarke of ADAS, who with colleagues has recently completed an HGCA-funded review of the impacts of forthcoming legislation on pesticide availability.
However, pesticide use is not the only farming practice the directive will affect. Farming impacts on water quality in a number of ways - through contamination from nitrates, phosphates, pesticides, soils, slurries and manures and through drainage and abstraction. Pesticides are a concern as a result of their effects on chemical status, although they may also have an ecological impact through possible effects on flora and fauna.
In England and Wales the Environment Agency (SEPA in Scotland) is responsible for implementing the legislation, monitoring progress and meeting the standards set out by the Directive.
As part of the implementation process it has established 11 RBDs which will be used to manage water environments. In Scotland there is one RBD, with a further two overlapping into England. Monitoring programmes were started in 2006 to give an overview of the water quality status of each district and to identify significant water management issues.
Currently, Defra and SEPA are consulting on River Basin Management Plans developed for each RBD. The consultation runs until June 2009 (www.environment-agency.gov.uk/research/planning/33106.aspx and www.sepa.org.uk/about_us/consultations.aspx). Following the consultation, management plans will be implemented between 2009 and 2012. There is a planned review of progress every six years, the first of which will take place in 2013.
The biggest challenges to water quality are from pesticides and nutrients. An Environment Agency monitoring programme is already in place for the nine plant protection products most commonly found in surface water. These are all herbicides which are relatively mobile and persistent: atrazine, chlorotoluron, 2,4-D, dichlorprop, diuron, isoproturon, MCPA, mecoprop and simazine. Some of these products are already in the process of being withdrawn; IPU is due for withdrawal in 2009 and some have already been removed from the market, including atrazine, diuron and simazine. Ecological quality requirements under the WFD may mean that all insecticides and chlorothalonil are also at risk.
Water companies have a legal requirement to test their water for pesticides and report their findings to the Drinking Water Inspectorate.
The failure rate for pesticides is low but some active substances are more commonly reported, including propyzamide, chlorotoluron, mecoprop, isoproturon and, more recently, metaldehyde.
Based on these findings the use of a number of active substances used in cereals and oilseed rape could be threatened under the WFD, says Mr Clarke.
“The implementation of the WFD is likely to impact on a number of important active substances.
“The active substances that are most likely to be affected are those used on a large area and/or at high rates. This makes herbicides particularly vulnerable as large areas of combinable crops have high rates of active substance applied to them in the form of herbicides.
“As a result, about 10 herbicides are causing concern with relation to the WFD. This includes a number of important actives for the control of grass weeds in oilseed rape. If restrictions or withdrawals for the use of these chemicals occur it could make the control of black-grass and other grass weeds almost impossible. If cropping systems remained the same, in affected areas this could lead to yield losses similar to those seen in untreated crops, of about 35 per cent.”
Many of the insecticides are also likely to be at risk from the WFD. As a result, future options for control of some pest species could potentially be very limited. Slugs in particular could be difficult to control as metaldehyde is already under scrutiny because it is being found in water and, if it is lost, the area treated with methiocarb is likely to increase, putting it at a similar risk of starting to appear in water. This could potentially leave growers with no good molluscicides for slug control.
What has become clear during the process of implementing the WFD is that changes in farming practice will to be needed to meet the directive's objectives on water quality. The legislation has been structured in such a way that the competent authorities - the Environment Agency and SEPA - are not limited in terms of the tools which can be used to modify farming practices to reduce pollution, although the aim is very much for a joint voluntary approach with stakeholders.
Options include funded schemes, such as the agri-environment schemes or industry-led initiatives such as the Voluntary Initiative and the Metaldehyde Stewardship Scheme. Some of the instruments likely to be employed are already in use - the Integrated Pollution Prevention and Control Directive, the Nitrate Directive, Catchment Sensitive Farming, the VI, Tried and Tested nutrient management planning - says NFU water policy adviser Michael Payne.
“Defra is of the view that we are already half way to meeting WFD targets just as a result of taking these actions but additional advisory, funded and regulatory measures will be needed to bridge the gap,” he says.
Approaches may well vary between RBDs according to their priorities.
“Particular catchments may impose different limits. There are different plans for different RBDs, which have different priorities. So for example in the Anglian region the priorities are diffuse pollution - including nitrates, phosphates and sediment - point source pollution, abstraction and physical modifications such as drainage. In the Thames/Cherwell RBD pesticides are more of a priority.”
It is almost certain that the Environment Agency will have the power to impose changes if voluntary measures are not working. A consultation on Defra proposals to designate Water Protection Zones to regulate where necessary under the WFD closed on March 31, 2009.
“Government has rejected economic instruments - taxes - but has selected Water Protection Zones has a regulatory instrument of last resort,” says Mr Payne.
Water Protection Zones (WPZs) would be used to control activities causing water pollution within a particular area. They could be applied over any scale and target almost any pollutant or polluting activity. However they can only be created following consultation and secondary legislation. Only one WPZ exists currently on an industrial area on the River Dee. There is a pilot WPZ in the Cherwell RBD and eight candidate WPZs have been designated.
NFU plant health adviser Paul Chambers believes that Water Protection Zones should be used only if all other measures have failed.
“Voluntary Initiative-type measures are the first step, then an intermediate stage beyond these might be for example pesticide specific mandatory buffer zones. The next step could be a WPZ,” he says.