DRENTHE TAKES ACTION TO REDUCE RISKS OF PESTICIDES; NUMBER OF HARMFUL SUBSTANCES AND CROPS STILL REQUIRING ATTENTION

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1 DRENTHE TAKES ACTION TO REDUCE RISKS OF PESTICIDES; NUMBER OF HARMFUL SUBSTANCES AND CROPS STILL REQUIRING ATTENTION Cors van den Brink 1,!, Anton Dries 2, Carolien Steinweg 1 and Willem Jan Zaadnoordijk 3 1 Royal HaskoningDHV, PO Box 8064, 9702 KB Groningen, the Netherlands 2 Province of Drenthe, PO Box 122, 9400 AC Assen, the Netherlands 3 KWR Watercycle Research Institute, PO Box 1072, 3430 BB Nieuwegein, the Netherlands! Corresponding author: cors.van.den.brink@rhdhv.com ABSTRACT The presence of pesticides in groundwater and surface water threatens the sustainability of the drinking water supply and may jeopardise compliance with Water Framework Directive (WFD) targets. The Provinces of Drenthe (chair), Overijssel, Groningen, and Friesland cooperating with the local water boards and water supply companies have launched an inventory of the use and risks of pesticides and comparison of this information with available groundwater and surface water quality data. This research shows that over the last 15 years, the environmental risks of pesticides in the north-east of the Netherlands expressed in Environmental Impact Points (EIP) have been reduced by 80% - 90%. This reduction is achieved by using less and less harmful substances. Despite the reduction, pesticides in Drenthe still present a risk for the extraction of drinking water and for aquatic ecosystems. 28% of the groundwater and surface water concentrations in Drenthe exceeded the limits. The presence and risks of pesticides in Drenthe will be compared with the situation in the north-east of the Netherlands. Joint research in four provinces The four northern provinces commissioned research on the presence of pesticides in groundwater and surface water (Van den Brink et al., 2011). The research made use of data from water boards relating to pesticides found in the surface water and data from the provinces about pesticides in groundwater collected under the Water Framework Directive. The figures for Drenthe are 95 measured points in the surface water (period from 2000 to 2009) and 18 measured points in the groundwater (period from 2006 to 2008). Groundwater was measured at a depth of approx. 10 and 25 metres below surface level. Samples were taken at the groundwater measuring points each year in the period from 2006 to The measuring frequency at the surface water measuring points varied per measuring point. The research also provides a description of the current risks for groundwater and surface water and for aquatic and terrestric ecosystems as a result of the use of pesticides Spray programmes were used to show the use of pesticides in the north-east of the Netherlands. Such use relates to the agricultural use of pesticides as well as the use of pesticides on nonagricultural land (for example industrial sites, recreation areas, wooded and nature conservation areas, allotments, roads, grassland and surfaced ground within local authority areas and private land). Measurement data on pesticides in Drenthe National standards, known as the Bkmw, are applicable to ascertain the level of risk associated with the measured concentrations with respect to the concentrations of pesticides in groundwater and surface water. Bkmw stands for the Dutch decree on quality requirements and monitoring in water. The standard level for individual pesticides is 0.1 µg/l, while the standard level for total pesticide content - known as the total standard - is 0.5 µg/l. These standards are the same as the WFD standards. Groundwater and surface water

2 quality were tested to check whether the levels comply with the Bkmw standard of 0.5 µg/l for the total content of pesticides detected. The figures show that standard levels for pesticides in groundwater and surface water are exceeded in Drenthe in line with the average for the north-east of the Netherlands. The standard level for the total content of pesticides (0.5 µg/l) was exceeded in 28% of the samples taken of the groundwater and surface water. Standard levels are exceeded the least in Friesland (13% in groundwater and 16% in surface water). The highest percentage of surface water data exceeding the standard level is in Groningen (43%). The percentage of groundwater samples exceeding the standard level is highest in Overijssel, at 32% (see Figure 1). Figure 1. Percentage of samples exceeding pesticide standards in surface water and groundwater in the Dutch provinces Drenthe, Groningen, Friesland and Overijssel. North-east of the Netherlands Drenthe Friesland Surface water Groningen Groundwater Overijssel % of readings exceeding the standard According to the researchers, the low percentages in Friesland are explained by the high proportion of grassland and the corresponding low use of pesticides on grassland in this province. Groningen's high percentage of surface water data exceeding the standard level is due to a combination of intensive arable farming and heavy soils, as a result of which a lot of water flows to the surface water via drains and ditches. The highest level of pollution to groundwater occurs in the sandy soils of Overijssel and Drenthe and in the peat areas of Drenthe and Groningen. A relatively high volume of pesticides is used in these areas due to the intensive arable farming there. The pesticides leach into the groundwater through the infiltrating rainwater. It is noticeable that standard groundwater levels are not exceeded in wooded and nature conservation areas. Pesticides are found in the surface water even in wooded and nature conservation areas due to the use of these substances upstream. If we compare the levels of shallow and deep groundwater exceeding the standard level, we see in agricultural soils a lower content of pesticides in the shallow groundwater than in the deep groundwater. This lower content is also in line with the trend set out in the Memorandum on sustainable crop protection (Van Eerdt et al, 2012). This seems to suggest a decrease in agricultural pollution. In urban areas, concentration decreases with depth. This may indicate an increase in the use of pesticides but could also be the result of increasing infiltration of rainwater in urban areas due to decoupling of the sewage water discharge and storm water discharge which facilitates the leaching of pesticides into the groundwater. According to the researchers, more detailed research is needed into the use of pesticides in urban areas.

3 Mapping the risks using spray programmes and environmental indicators In addition to describing the level of pesticides actually measured in groundwater and surface water, this Memorandum also maps the risks for groundwater and aquatic and terrestric ecosystems as a result of using pesticides. The risks are mapped in the north-east of the Netherlands, by calculating the use of pesticides on the basis of land use 1, soil type (especially the content of organic matter), cultivation plan, crop type and corresponding practical spray programmes in 1997 and This calculated pollution was converted into environmental risks based on Environmental Impact Points (EIP) via the environmental indicator developed by the CLM (Centre for Agriculture and the Environment). The higher the EIP score, the greater the risks for water and soil creatures and for the groundwater. A score of 100 EIP for groundwater per application corresponds to the standard level of an individual pesticide in the groundwater (0.1 µg/l), whereas a standard level of 500 EIP corresponds to the standard level of all pesticides (0.5 µg/l). Risk presented by pesticides significantly reduced; arable farming still has problem crops To illustrate the decrease in environmental risks of pesticides, a comparison was made between the 1997 and 2010 soil usage and spraying programmes. The comparison was based on practical data on the agricultural and non-agricultural use of pesticides. Pollution of the upper groundwater in 1997 was above the standard level in a large part of the province. The main crops with a high risk of pesticides leaching into the groundwater are cultivation plans with onions, lilies, winter corn, sugar beet, edible potatoes, potatoes for starch and corn. If we look at the map of Drenthe (see Figure 2), we can see 'red zones' spread throughout the province. These are arable farming areas. The 'yellow zones' are primarily grassland areas and built-up areas. 1 The LGN6 map was used for farming land use, the CBS function map from 2006 was used for spatial functions and the 2006 soil map was used for types of soil.

4 Figure 2. Risk for shallow groundwater (top meter of phreatic groundwater) due to the use of pesticides in 1997 in the Dutch province Drenthe. If we compare the situation in 1997 and 2010, we see a significant shift in substances and decrease in risk of approximately 80% to 90%. However, current risk is still above the standard level, especially in arable farming areas, despite the use of currently permissible substances and dosing levels. The main crops with a high risk of pesticides leaching into the groundwater are onions (approx. 850 EIP), lilies (approx. 115,000 EIP), sugar beet (approx. 500 EIP), edible potatoes (approx EIP) and potatoes for starch (6200 EIP). If we look at the map of Drenthe showing the 2010 situation (see Figure 3), we can still see 'red zones' spread throughout the province. These are arable farming areas on soils with a low content of organic matter that are prone to pesticide leaching. The incidence of pesticide leaching in

5 peat areas is lower due to the higher content of organic matter (pesticides adsorb to organic matter). Arable farming in these areas is reflected by the yellow zones on the map. Figure 3. Risk for shallow groundwater (top meter of phreatic groundwater) due to the use of pesticides in 2010 in the Dutch province Drenthe. The survey shows that the vast majority of the pesticides currently detected in groundwater and surface water can be explained by the spray programmes from 1997 (for groundwater) and 2010 (for surface water).

6 Clean groundwater of province-wide importance The province is the legal authority with respect to groundwater quality around groundwater extractions sites. Together with the Drenthe Water Supply Company (WMD), Groningen Water Company and Vitens, the province is responsible for ensuring sufficient and clean drinking water in Drenthe. The level of groundwater pollution within the groundwater protection areas is therefore very important. For this reason, researchers have compared pesticide usage inside and outside groundwater protection areas. They have found hardly any difference in pesticides applied inside and outside groundwater protection areas at a provincial level. When regarding individual farms, risks of using pesticides within groundwater protection areas may well be lower than outside such areas. For example, if the farmer in question is a member of one of the knowledge groups of the WMD, which supports farmers in the process of reducing the risks of pesticides, this farmer often uses a lower volume of or different substances with a lower environmental impact. The region around groundwater protection areas may also have benefitted from knowledge gained by study groups or by presentations held in the region. In addition, participating farmers often also have land outside the groundwater protection areas. However, this incentive scheme is not sufficiently attractive to significantly reduce the risks of pesticides on the scale of the entire groundwater protection area. Ever present need to reduce risks of pesticides For years, the Province of Drenthe has been active in reducing the risks of using pesticides in the province. From 1997 to 2010, the Province of Drenthe has pursued an incentives policy, together with the WMD, and has thereby helped to reduce environmental pollution from pesticides in groundwater protection areas. In 2009, on an initiative of the WMD and the province, the project "Bezem door de middelenkast" ("Clearing out old pesticide stores") was launched to collect and responsibly dispose of old pesticides. The Province of Drenthe also contributed to reducing the use and risks of pesticides in the bulb-growing industry in Drenthe by means of its project "Duurzame bollenteelt" ("Sustainable bulb-growing"). These projects, together with other initiatives such as the generic tightening of policy, have led to the specified decrease in the risks of pesticides. Need for further action Yet the need to further restrict the risks is still great. To this end, the province has set up Water Protection Files for all drinking water extraction sites in Drenthe since early A Water Protection File describes the status of the drinking water extraction site and the possible threats for the groundwater. This analysis has shown that pesticides have been detected in the extracted groundwater at drinking water extraction sites, especially at the vulnerable extraction sites. New analysis techniques used in the exploratory research carried out by the WMD indicate the presence of pesticides and metabolites2 (degradation products of pesticides) is much greater than initially thought, albeit in low concentrations. Although pesticides are extensively applied, their use in bulb-growing in particular leads to urgent risks for the quality of groundwater and surface water. The intensive bulb-growing activities in Drenthe also mean that pesticides such as carbendazim associated with bulb- 2 For 'human-toxicology-related metabolites', a standard level of 0.1 µg/l is applicable, for non-human-toxicologyrelated metabolites, the applicable indication value for anthropogenic substances is 1 µg/l. This refers inter alia to BAM (metabolite of dichlobenil) and AMPA (metabolite of glyphosate). BAM and AMPA are included in the range of analyses adopted by the Province of Drenthe in the process of monitoring pesticides in the WFD groundwater monitoring network. The main problem with metabolites is not the standard level, but the fact that the metabolites formed are not known. This means that it is not possible to specifically search for metabolites, so the risk cannot be excluded that such substances impact on the quality of groundwater.

7 growing are detected in the Drentsche Aa. The Drentsche Aa is the only surface water used for the production of drinking water in Drenthe. The research shows that the presence of less than a 1% bulb-growing in the cultivation plan in the sandy areas in Drenthe leads to a significant increase in the risks of pesticide leaching into the groundwater of the overall cultivation plan due to pollution of 115,000 EIP per year compared with an average pollution of approximately 3,000 EIP per year. This problem is exacerbated by the fact that bulbgrowing keeps starting up in different places within the province due to contract farming, thus posing a risk to the groundwater in various places in an unpredictable pattern. Effective measures therefore have to be taken in the short term to tackle the risks of bulb-growing for groundwater, surface water and in particular drinking water supply. Measures (ongoing) Under the aegis of the Province of Drenthe, the Drenthe authorities started the process of certification as of 2010 in accordance with the Barometer Duurzaam Terreinbeheer (barometer for sustainable land management), to reduce the use of pesticides on grassland and surfaced ground as much as possible. The project "Schone bron Drentsche Aa" ("Clean source Drentsche Aa") was launched in The project is run by the Groningen Water Company (leader), Hunze & Aa's Water Authority and the Province of Drenthe. The aim is to obtain a better understanding of the origin of pesticides (via additional monitoring) and increase awareness among users. Target groups are farmers (incl. contract companies), local authorities, companies and private individuals. In 2012, the Province of Drenthe, Drenthe local authorities, water boards, WMD and the Groningen Water Company launched the campaign "Zonder is gezonder" ("It's better without") to reduce the use of chemical pesticides by private individuals. Also in 2012, the Province of Drenthe initiated the project "Duurzame Akkerbouw" ("Sustainable arable farming"), specifically aimed at reducing the risks posed by pesticides. It aligns with the approach developed by the Veldleeuwerik Foundation. Under the Veldleeuwerik Foundation, arable farmers and food-processing companies work together to boost the sustainable production of arable farmland. Under the leadership of the Province of Drenthe, a project was launched in 2012 to jointly elaborate a strategy with the parties involved, with the aim of making concrete agreements about reducing the risks of pesticides. The type of measures to be agreed are worked out on the basis of knowledge about the use and risks of pesticides. In 2012, agreements will be made between the water companies, LTO Noord (National farmers organisation), the Rijkswaterstaat (Directorate-General for Public Works and Water Management), ProRail (rail infrastructure company) and the corresponding local authorities about reducing the risks involved in the process of extracting drinking water. A key component of these discussions will be to enter into agreements about effective measures for reducing the risks of using pesticides. By means of these and other initiatives, the province - together with the parties involved - is fulfilling its specific task with respect to protecting groundwater quality in general and reducing the risks of pesticides in particular. However, the initiatives also show that when it comes to pesticides in Drenthe, a sustainable balance has not yet been achieved between the use of space above ground and the risks that this entails for groundwater quality and drinking water supply. This is applicable for urban as well as rural areas.

8 References Van den Brink, C., C. Steinweg and W.J. Zaadnoordijk (2011). Bepalen strategie vermindering risico's bestrijdingsmiddelen Noordoost Nederland (Elaborating a strategy for reducing the risks involved in using pesticides in the north-east of the Netherlands). Project on behalf of the Province of Drenthe, Province of Friesland, Province of Groningen and Province of Overijssel. Final report 22 July Reference Royal Haskoning report no. 9V5482. Van Eerdt, M., J. van Dam, A. Tiktak, M. Vonk, R. Wortelboer and H. van Zeijts (2012). Evaluatie van de nota Duurzame gewasbescherming (Evaluation of the Memorandum on sustainable crop protection). Planbureau voor de Leefomgeving. ISBN: PBL-issue number