Post on 24-Dec-2015
Emerging Surface Water Issues And Pesticides
- CURES -Coalition For Urban/Rural
Environmental Stewardship
Problem: Pesticides In Urban Runoff
• Pesticide detections on the rise.• Regulators seeking voluntary
solutions.• If not solved soon, regulatory action
is likely.
Why Is Surface Water Issue Emerging?
• EPA and states moving from point to non-point pollution.
• More attention to managing non-point source pollution.
Key Player: the Water Flea
• Water flea (ceriodaphnia dubia).• Indicator species.• Sensitive at parts per trillion.
Detections in CA Rivers and Streams
• Some samples toxic to water flea.• Only in occasional spikes.• Not above health advisory levels.• Regulations in the works.
Pesticides Detected In Delta Tributaries
Alachlor - Lasso/Lexan
Atrazine
Carbaryl - Sevin
Chlorpyrifos - Lorsban
Dieldrin
Cynazine - Bladex
Diuron - Karmex
Diazinon
Dacthal
EPTC - Eptam
Fonofos - Dyphonate
Malathion
Pebulate - Tillam
Metolachlor - Dual
Molinate - Ordram
Napropamide - Devrinol
Methomyl - Lannate
Pronamide - Kerb
Propargite - Comite/Omite
Simazine - Princep
Triflurilin - Trelan
DDE, p, p
(Salt Slough, Orestimba Creek, Merced River)
Pesticides Detected In Urban CreeksNewport Bay Carbaryl - Sevin
Chlorpyrifos - Dursban
Benomyl - Benlate
Diuron - Karmex
Diazinon
Methidathion - Supracide
Methomyl - Lannate
Pendimethalin - Prowl
Malathion
Oryzalin - Surflan
Simazine - Princep
Triflurilin - Trelan
Nonpoint Source Contamination (NPS)
• Improper application of chemicals.– spray drift– aerial spray or dumping over water
• Irrigation – Tailwater runoff– Leaching
• Overland runoff– heavy rain
Nonpoint Source Contamination (NPS)
• Mixing and Loading
– No containment
– Improper site
• Urban Runoff
– Urban streams
Point Source Contamination
• A “driver” for non-point source regulations.
• Based on Clean Water Act regulations.
– Permitted Discharges
• Manufacturing
• Water treatment plants
• Storm runoff
Why Now?
• Technologies of detection: part per trillion.
• Ease of using testing kits.
• Emphasis shift from point to nonpoint sources.
• Increased monitoring -- just beginning.
– USGS, State activities
• $$$$ for monitoring.
– CWA, State funds, CalFed
What the Issue is Not About
• Human health concerns.
• Direct effects on fish.
• Ecological significance?
• Persistent toxicants.
What the Issue Is About
• Recurring part per trillion level of pesticides.
• Initial focus on organophosphate insecticides.
• Toxicity to a sensitive screening organism.
– Water flea: Ceriodaphnia dubia
What the Issue Is About
• FIFRA vs. Clean Water Act Standards.
• Overlapping jurisdictions.
– DPR and State/Regional Water Boards
• The need for refined science: what is
ecological significance?
• Science-based regulations needed.
What is the Clean Water Act Process?• Identify impaired waters - 303(d) Lists.
– Revised every two years
• Prioritize Total Maximum Daily Load development.
• Develop TMDL’s.
– quantitative assessment of water quality problem
– sources
– actions to restore/protect the water body
Pollutants/Stressors in 303(d) Listings
• Fertilizer/Nutrients
• Pathogens (e coli,
coloform)
• Sediment
• Pesticides
• Metals (mining runoff)
• Salinity
• Diazinon
• Chlorpyrifos
TMDL - Total Maximum Daily Load
TMDL = point sources + non-point sources +
background + margin of safety.
TMDL Litigation by States
• EPA under court order to establish TMDL’s
– OR, AK, GA, CA (North Coast), PA, AZ, NM, WV, DL, CA (Newport Bay)
• Litigation filed (December 1997)
– D.C., AL, FL, MS, CA (Los Angeles)
• 42 cases
CA Urban Creek TMDL Priorities
• OP Pesticide TMDLs for CA urban creeks
– Chollas Creek, San Diego: due April 2000.
– Upper Newport Bay, urban creeks, Orange County: due Jan. 2002.
– San Francisco Bay, urban creeks: due 2002/03.
– Sacramento/Stockton, urban creeks: due 2012 (pressure to complete on SF Bay timeline).
Newport Bay TMDL Priorities
• Preliminary staff report - March 2000
• TMDL draft language in 3-6 months later.
• Public hearings/stakeholder meetings.
• Finalize mitigation measures.
• To Office Administrative Law to finalize.
Newport Bay Problem
• Toxicity from almost all storm events.
• Highest toxicity ever found in state.
– 50% from Chlorpyrifos, Diazinon
• Unknown persistence beyond 96 hrs.
Potential TMDL Impacts
• Pressure for regulatory controls on agriculture, urban and other non-point sources
• Wasteload allocation with little data or science
• Tighter discharge limits on point source permits
CA Pesticide Water Quality Program
• MAA (Management Agency Agreement) between DPR, Ag Commissioners, and State Water Resource Control Board - Feb. 1997
• Developed to:
– address overlapping authorities
– reduce duplication of effort, inconsistencies, confusion of regulated public
Pesticide Management Plan (PMP) for Water Quality
• Implements the Management Agency Agreement
• Mitigate problems using phased approach:
– Stage 1: Outreach & Education - preventative
– Stage 2: Self Regulating - sponsors
– Stage 3: Regulatory (DPR & Commissioners)
– Stage 4: Regulatory (State/Regional Water Boards)
Why Best Management Practices?
• Are BMPs the answer?• What are my alternatives to BMPs?• BMPs will slow down the process.
What happens if BMPs are adopted?
• No regulations (ideally).• Exemptions.• Less severe restrictions in the future.
Urban BMPs
• Goal: Control non-point source pollution
– Reduce off-site transport of sediment, nutrients,
pesticides.
Urban BMPs
• Transport Mechanism: How’s it moving off-site?– Stormwater runoff– Irrigation runoff– Washed off during hose down– Drains in building/facility/home
Urban BMPs
• Stormwater Runoff: manage potential movement – Don’t spray just before storms.
– No overspray on hard surfaces; sweep up granules from driveways.
– Consider alternative controls in areas where stormwater channels or drains off the site.
– Evaluate drain pest treatments.
Urban BMPs
• Irrigation Runoff
– Avoid overwatering to point of runoff.
– Consider frequent light irrigations (when product
must be watered-in to turf or landscape.)
Urban BMPs
• Building/facility/home drains
– Drains eventually reach river/ocean.
– Don’t dispose of rinsewater in drains.
– Don’t dispose leftovers in drains.
Urban BMPs
Pest Control Practices
• Take an IPM approach
• ID the pest, host, habitat
• Consider all control options
• Treat only where needed
• Monitor results
Best Management Practices
• Surface water– vegetation buffer strips – water holding periods– containment/catch basins – application buffers – mixing areas w/containment and rinsate recycling
Vegetation Buffer Strips
• 20-foot wide vegetation strip along waterways and on downhill side of field
• Plant cover crop– legumes– native perennial grasses
• Physical barrier– slows water - sediment deposition– captures/absorbs available materials
Mixing and Loading
• Contained concrete mixing/loading pad
• Flat area, disked or graveled
• Recycling system for rinsate
• Recycle rinsate into the spray mix
• Spray rinsate on the field
• Stay away from wells
Sprayer Technology
• Use dry locks on spray equipment• Increase droplet size
– use drift retardants– avoid windy spray conditions (see label)
• Equipment maintenance– avoid leaks and broken hoses
• Turn sprayer off at end of row
Managing Drift From Airblast Sprayers
• Most drift comes from outside 2 rows– First/last passes through the orchard
• Don’t spray inside of row 1 or 2 • Spray outside -inward on perimeter rows, slowing
down to improve coverage.
Managing Drift From Airblast Sprayers
• Direct spray at canopy, not open spaces.– Base of tree and gap between rows (straight up) – Almond canopy begins 6 feet from ground.
• Set nozzle angle to cover target only.• Canopy is the greatest interceptor of spray. • Use nozzles that produce bigger droplets.
Tough Questions Yet To Be Answered
• Which programs will “trump.”
• What will those programs look like?
• Which best management practices
will solve the problem?
What Needs To Be Done by Regulators? • Better Define Problem
– Extent of impact– Which pesticides– Characteristics of pesticides
• Source Identification– Where they coming from?
• BMP Development• Address Regulatory Issues
– CWA, Stormwater agencies, etc
What Does The Future Hold ...
• Who shapes our future?
– Industry
– Regulators