PesticidesPesticides inin IowaIowa’’ss WaterWater Resources:Resources: HistoricalHistorical TrendsTrends andand NewNew IssuesIssues MaryMary P.P. SkopecSkopec andand KatieKatie ForemanForeman WatershedWatershed MonitoringMonitoring andand AssessmentAssessment IowaIowa DepartmentDepartment ofof NaturalNatural ResourcesResources OutlineOutline PesticidePesticide UseUse inin IowaIowa CurrentCurrent StatusStatus andand HistoricalHistorical TrendsTrends NewNew ApproachesApproaches forfor UnderstandingUnderstanding Occurrence of Pesticides in Water Resources Function of: 1. Use 2. Soil Characteristics 3. Rainfall Timing and Amount 4. Pesticide Properties Land Use in Iowa (2002) Percent of Iowa Acres Treated Herbicides Insecticides Yes No Source: Pesticide Movement: What Farmers Need to Know, Iowa State Extension, PAT-36 2000, Non-City Stream Sites 2001, Non-City Stream Sites 2002, Non-City Stream Sites 2,4-D* 2,4,5-T* Acetochlor Acifluoren* Alachlor Ametryn Atrazine Atrazine, Deethyl Atrazine, Deisopropyl Bentazon* Bromacil* Some Bromoxynil* Butylate Very Chloramben* Cyanazine Dalapon* Common; Herbicides Dicamba* Dichloprop* Others Dimethenamid EPTC Less so Metolachlor Metribuzin Pendimethalin* Picloram* Prometon Propachlor Propazine Simazine Triclopyr* Trifluralin Carbaryl* Carbofuran* Chlordane* Chlorpyrifos* es DDD* DDE* id DDT* Few ic Diazinon* ct Dieldrin* Detects Fonofos* Lindane (gamma-BHC)* Inse Malathion* Parathion* Phorate* 0 204060801000 204060801000 20406080100 Detection Rate, in Percent Detection Rate, in Percent Detection Rate, in Percent * Parameters analyzed April through July; all others analyzed monthly. Pesticide Concentration for Non-City Sites Pesticide Concentration for City Sites 160 60 140 50 120 L) 40 g/ g/L) 100 (u on tion (u 80 30 a r entrati ncent 60 o 20 C Conc 40 10 20 0 0 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Month (2001) Month (2001) Acetochlor Acetochlor Alachlor Alachlor Atrazine Atrazine Cyanazine Cyanazine Dimethenamid Dimethenamid Metolachlor Metolachlor Prometon Prometon Simazine Simazine Trifluralin Trifluralin Median Pesticide Concentration 2000-2002 (µg/L) $T #S #S #S #S #S #S #S $T #S $T #S $T #S $T$T #S #S$T $T $T$T #S $T $T $T $T $T $T $T #S #S #S $T $T $T $T $T$T #S $T $T $T $T $T #S $T $T%U %U $T %U $T%U $T %U %U %U$T %U $T %U %U %U %U %U %U $T %U %U $T %U %U $T %U Median Atrazine 2000-2002 (µg/L) %U #S <0.05 $T 0.05 - 0.1 %U >0.1 Major River Basins Rivers Counties Median Pesticide Concentration 2000-2002 (µg/L) #S #S #S #S #S #S #S #S #S #S #S #S #S #S #S#S #S #S #S #S#S #S $T#S #S #S #S $T #S $T $T #S #S #S #S #S #S #S #S#S #S %U #S #S #S #S #S $T #S #S #S$T #S #S #S #S #S $T #S #S $T#S #S #S $T #S #S #S %U $T #S $T #S #S #S %U #S #S Median Metolachlor 2000-2002 (µg/L) #S #S <0.05 $T 0.05 - 0.1 %U >0.1 Major River Basins Rivers Counties LimitedLimited MonitoringMonitoring HistoricallyHistorically ProjectProject DrivenDriven StudiesStudies FewFew LongLong TermTerm SitesSites (16(16 ambientambient sincesince 19861986 withwith quarterlyquarterly sampling)sampling) IAPESTIAPEST –– CompilationCompilation databasedatabase ofof allall availableavailable pesticidepesticide datadata inin IowaIowa id enam Herbicide Use - eIowath Metolachlorhosate p Dim ralin Gly Triflu 2001 2000 poral Trends in 1999 Tem 1998 Acetochlor 1997 Alachlor Atrazineanazine 1996 Cy 1995 1994 20000 1993 1992 15000 1991 Year 1990 1989 10000 1988 1987 5000 1986 Annual Use (1000 lbs) 0 1985 Mean Concentrations of Surface Water Sites 1990-2002 10 Year vs Atrazine Year vs Alachlor Year vs Acetochlor Year vs Cyanazine L) Year vs Metolachlor g/ µ on ( i 1 at r oncent Mean C 0.1 1990 1992 1994 1996 1998 2000 2002 Mean Concentrations of Groundwater Sites 1 Year vs Atrazine Year vs Alachlor Year vs Acetochlor Year vs Metolachlor g/L) µ ion ( Mean Concentrat 0.1 1990 1992 1994 1996 1998 2000 LinkingLinking UseUse toto OccurrenceOccurrence LackingLacking detaileddetailed datadata onon pesticidepesticide useuse RequiresRequires indirectindirect methodsmethods ofof estimationestimation IowaIowa GroundwaterGroundwater ProtectionProtection ActAct ofof 19901990 SalesSales ofof pesticidespesticides reportedreported byby DealerDealer Process for Converting Reported Sales Data Sales Data Reported to IDALS Dollars are Converted to Lbs –> ISU Ext Link Lbs to Zip Code and Sum by County GIS Coverage of Sales Stream Watersheds with Zip Codes Superimposed N W E S Distributing Sales by Point Locations Kernel Modeling: Decay Function from centroid to boundary # # # N W E S HowHow DoesDoes ModelModel Compare?Compare? SalesSales vs.vs. MeasuredMeasured WaterWater QualityQuality EnvironmentalEnvironmental LagsLags maymay blurblur resultsresults MonitoringMonitoring maymay notnot perfectlyperfectly matchmatch salessales locationslocations oror densitydensity graphsgraphs Median Pesticide Concentration 2000-2002 (µg/L) $T #S #S #S #S #S #S #S $T #S $T #S $T #S $T$T #S #S$T $T $T$T #S $T $T $T $T $T $T $T #S #S #S $T $T $T $T $T$T #S $T $T $T $T $T #S $T $T%U %U $T %U $T%U $T %U %U %U$T %U $T %U %U %U %U %U %U $T %U %U $T %U %U $T %U Median Atrazine 2000-2002 (µg/L) %U #S <0.05 $T 0.05 - 0.1 %U >0.1 Major River Basins Rivers Counties Water Quality from Selected Watersheds r Big Spring (BSP) Iowa River at Columbus Jct E. Nishnabotna R. nr Shenandoah e in z a Atr ing Spr Big 2004 2002 2000 1998 1996 10 1994 1992 ear 1990 Y L 1 µg/ 1988 1986 1984 0.1 1982 ver at Shenandoah a Ri n Atrazine shnabot Ni East 2004 2003 2002 100 2001 2000 10 1999 Year 1998 µg/L 1 1997 1996 0.1 1995 Atrazine 10 IowIowaa Riv Riverer at Col atu mColumbusbus Junction Junction 1 µg/L 0.1 19 19 20 2 20 0 9 98 0 02 04 6 0 Year SummarySummary UseUse ofof ““traditionaltraditional”” herbicidesherbicides droppeddropped ChangingChanging useuse reflectedreflected inin locallocal watershedswatersheds SomeSome watershedswatersheds havehave experiencedexperienced locallocal increases;increases; othersothers decreasesdecreases ImproveImprove targetedtargeted managementmanagement activitiesactivities Questions?Questions? [email protected] Alachlor ESA Degradate Concentrations in Surface Water 1995-2002 100 10 ) L g/ µ 1 A ( r ES o 0.1 achl Al 0.01 0.001 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 Year Acetochlor ESA Degradate Concentrations Surface Water 1995-2004 100 10 ) L g/ µ A ( 1 or ES hl c 0.1 Aceot 0.01 0.001 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 Year.