Stormwater Runoff & Pesticides What Monitoring Done Elsewhere May Suggest for South Portland

Transcription

1 Stormwater Runoff & Pesticides What Monitoring Done Elsewhere May Suggest for South Portland South Portland City Council Workshop 8/8/16 Fred Dillon Stormwater Program Coordinator

2 Stormwater 101 What stormwater is How stormwater picks up pollutants How stormwater collection systems work What stormwater references & research reviews suggest about prevalence of pesticides in urban watersheds Pesticides studies done elsewhere Where to find more studies How relevant is this research to South Portland?

3 What is Stormwater? Stormwater is precipitation or melted snow flowing over the land plus anything carried along with it.

4 Polluted Stormwater Drainage systems also carry pollutants like sediment, oil, fertilizers, pesticides, salt, pet waste and trash. Rainwater that falls on paved streets, lawns, parking lots and sidewalks becomes polluted stormwater.

5 Municipal Piped Infrastructure

6

7 Stormwater Effects Handbook (2001) Nationwide studies* show virtually every urban watershed contains elevated levels of pesticides in surface & groundwaters, sediments and fish tissues *Numerous studies cited

8 Urban Stormwater Management in the US National Research Council of the National Academies (2008) CONTEXT Stormwater runoff one of greatest modern water pollution challenges Stormwater pollution principle contributor to WQ impairment nationwide Problem likely to grow with population shifts to urban settings & associated landscape changes

9 Urban Stormwater Management in the US National Research Council of the National Academies (2008) GOALS Review CWA permitting programs Improve understanding of links between stormwater pollution and ambient WQ Assess state of science and make policy recommendations

10 Urban Stormwater Management in the US National Research Council of the National Academies (2008) FINDINGS (pesticides) Pesticides detected in 97% of urban stream water samples across US Human health and aquatic life benchmarks exceeded 6.7 and 83% of the time, respectively (USGS, 2006) Organochlorine compounds* were detected in 94% of fish tissues sampled in urban areas nationwide *Mostly banned though a few still registered in US

11 Urban Stormwater Management in the US National Research Council of the National Academies (2008) RECOMMENDATIONS (pesticides) More vigilant EPA oversight EPA to make better use existing licensing authority States to enact restrictions / taxes Local efforts to help motivate broader scale, federal restrictions on particular products

12 WQ in the Connecticut, Housatonic & Thames River Basins (CT, MA, NH, NY & VT, )* Land use & pesticide concentrations in streams are related Different numbers/types pesticides detected in urban, ag and forested areas 27 pesticides or degredates detected in urban samples *USGS Study

13 Occurrence of Lawn Care & Agricultural Pesticides in Don River & Humber River Watersheds ( ) 152 pesticides & active ingredients Samples collected during wet & dry conditions Objectives to determine which pesticides detectable ~72% of samples had at least 1 lawn care pesticide

14 Ecological Health in the Nation s Streams, (USGS) Dissolved pesticide concentrations > EPA ALBs* in more than half assessed streams in both ag & urban settings Potential to adversely affect aquatic organisms Pesticides commonly applied as mixtures may have greater toxicity than single compounds *ALB = Aquatic Life Benchmark

15 Ecological Health in the Nation s Streams, (USGS) Macroinvertebrate Community Alteration & Potential Toxicity of Pesticides Macroinvertebrates altered more often with increasing pesticide levels Insecticides detected most frequently & potentially toxic pesticides found in ag & urban areas Increasing potential toxicity of mixtures

16 Fresno-Clovis SW Quality Monitoring Program Evaluation of Basin EK Effectiveness Diazinon in stormwater discharged to treatment basin following EPA prohibition for most non-ag uses Concentrations decreased to levels below toxicity thresholds for freshwater aquatic life SOURCE: Fresno Metropolitan Flood Control District, November 2006

17 Contaminants in Stream Sediments from 7 US Metro Areas* Part I: Distribution in Relation to Urbanization (Jan. 2012) Watershed urbanization increases contaminant loadings to aquatic ecosystems and sediments important contaminant repository Organochlorine pesticides, PCBs, PAHs, and trace elements are frequently monitored and found in urban stream and lake sediments Pyrethroid insecticides emerged recently as contaminants of concern in urban streams with toxic concentrations reported in sediments of small urban streams especially near stormwater or sewage discharges *98 streams in 7 metro areas across US in 2007 with wadeable stream sites in most areas

18 Northeast Stream Quality Assessment (Current USGS Study*) OBJECTIVES Determine stream quality Nutrients, contaminants, toxicity, sediment, flow, habitat and biological communities Assess influence of chemical & physical stressors on biota Assess relations between watershed characteristics and measured stressors and biota Develop models and management tools to predict stressors and ecological conditions *95 sites sampled Jun-Aug 2016

19 Northeast Stream Quality Assessment (Current USGS Study*) Daily Pesticide Sampling 7 sites to assess short-term variations in concentrations of pesticides & degradates Daily and weekly composite samples Analyzed by EPA s Office of Pesticide Programs Valuable info for determining short-term acute exposure of aquatic organisms to pesticides and for optimizing temporal sampling strategies

20 USGS Pesticide National Synthesis Project

21 USGS Pesticide National Synthesis Project

22 Pipes Type Lineal Feet Lineal Miles Stormwater Gravity Line 348, Culverts 12, Combined Sewer Overflow 2, Roof Drain 6, Totals: 369, Structures Type Catch Basin Drain Manhole Combined Catch Basin Outlet Control Structure Total: Count 2, ,835