Pesticides Pollutants From Urban Landscapes

Transcription

1 Pesticides Pollutants From Urban Landscapes Why Landscape Runoff Matters Loren Oki CE Specialist, Landscape Horticulture Departments of Plant Sciences and Environmental Design Ant IPM Conference November 1, 2012 Photo: L.Oki

2 Sacramento Bee July 14, 2006

3 The Mayhew Drain in the Rancho Cordova area carries stormwater to the American River. A new study found enough pyrethroid pesticides in the American River to kill tiny shrimp among the first links in the aquatic food chain. Much of it is coming from Sacramento s runoff, the study found.

4 Pesticide Application About 50% of all pesticides purchased by homeowners are used to control ants

5 Irrigation Management Photos: D. Haver

6 Urban Drool Photos: D. Haver

7 Proper Design and Management Photos: L. Oki

8 Proper Design and Management Photo: L.Oki Photo: D. Haver Photos: L. Oki

9 Proper Design and Management Photos: D. Haver

10 Photo: D. Haver Photo: L. Oki Photo: L. Oki

11 Pesticides in Urban Runoff Runoff Monitoring Continuous Data Collection Flows (depth & velocity) Temperature ph Electrical conductivity Rainfall Automated Stormwater Sampling Remote Communication Photos: L.Oki

12 Pesticides in Urban Runoff Runoff Monitoring Continuous Data Collection Flows (depth & velocity) Temperature ph Electrical conductivity Rainfall Photos: L.Oki

13 Dry season runoff patterns Daily Periodicity 8 7 Tue July 1 Wed July 2 Thu July 3 Fri July 4 Sat July 5 Sun July 6 Mon July 7 6 Water Depth (cm) :00 12:00 0:00 12:00 0:00 12:00 0:00 12:00 0:00 12:00 0:00 12:00 0:00 12:00 0:00 Time of Day

14 Dry season runoff patterns Daily Periodicity 8 7 Tue July 1 Wed July 2 Thu July 3 Fri July 4 Sat July 5 Sun July 6 Mon July 7 6 Water Depth (cm) :00 12:00 0:00 12:00 0:00 12:00 0:00 12:00 0:00 12:00 0:00 12:00 0:00 12:00 0:00 Time of Day

15 Water Sample Collection Sacramento County UC Master Gardeners Photo: L.Oki Photo: L.Oki

16 Water Sample Collection Sampling Schedule Q1 Q2 Q3 Q Weekly* Weekly 2007 Biweekly Weekly Weekly Weekly 2008 Biweekly Biweekly Biweekly Weekly 2009 Monthly Monthly* None None 2010 None Monthly Monthly Monthly Up to 5 early storms of each season

17 Pesticide Detection Rates Sacramento County Diazinon Chlorpyrifos Fipronil Bifenthrin Fenpropathrin L-Cyhalothrin cis-permethrin trans-permethrin Cyfluthrin Cypermethrin Esfenvalerate Deltamethrin % Detection n= Diazinon Chlorpyrifos Fipronil Bifenthrin Fenpropathrin L-Cyhalothrin cis-permethrin trans-permethrin Cyfluthrin Cypermethrin Esfenvalerate Deltamethrin Orange County n=49

18 Pesticide Concentration Orange County neighborhoods Site A Site B Site C Site D Max Median Max Median Max Median Max Median diazinon 2, fipronil 10, , bifenthrin , no. samples Concentrations are in ng/l (ppt) 96 hr LC 50 organism diazinon 436 Ceriodaphnia dubnia fipronil 140 Americamysis bahia bifenthrin bifenthrin Ceriodaphnia dubnia Hyalella azteca

19 The Metabolite Issue fipronil Anaerobic conditions (reduction) fipronil sulfide Aerobic conditions (oxidation) fipronil sulfone Photochemical (photolysis) desthiofipronil

20 Fipronil Toxicity Aquatic Rainbow trout Bluegill Sheepshead minnow Grass shrimp Mysid shrimp Daphnid LC ppb 85 ppb 130 ppb 0.32 ppb 0.14 ppb 190 ppb Degradate Relative Toxicity Approx ½ life (d) Fipronil sulfone ~6x Fipronil sulfide ~2x Desthiofipronil ~8x

21 The toxicity of pollutants is sometimes measured in parts per trillion (ppt). If Folsom Lake holds 1 million acre-feet at capacity, how much is 1ppt in that lake? 1. A can of soda (12 oz.) 2. A 2 liter soda bottle 3. A 55 gallon drum 4. A railcar (22,800 gal) 5. The UC Davis water tower (200,000 gal) 6. An olympic-size swimming pool (660,000 gal)

22 The toxicity of pollutants is sometimes measured in parts per trillion (ppt). If Folsom Lake holds 1 million acre-feet at capacity, how much is 1ppt in that lake? Convert acre-feet to liters 325,851 gal/acre-foot and L/gal Folsom Lake is 325,851,429,000 gals or 1,233,477,999,337 liters That s 1.2 trillion liters So, 1ppt in Folsom Lake is 1.2 liter

23 Controlling Pollutants in Runoff Objectives Coordinate applications with irrigation and rain Prevent applications to irrigated locations that generate runoff Don t generate runoff Proper irrigation system design and management Hold runoff on-site Water that falls on the site, stays on the site

24 Thank you

25 Basic Properties of Fipronil Property Value Ranking Solubility 2 ppm Moderate Adsorption (K oc ) 800 Low-Moderate Hydrolysis T 1/2 >100 days Stable Turf T 1/ days Short Bare soil T 1/ days Moderate * Sulfone and sulfide have higher Koc. Fate in sediment or water unknown.