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Kathy Brohawn Technical & Regulatory Services Administration Maryland Department of Environment

Recreational Water Quality Standards, Bacteria Monitoring Chesapeake Bay Program Living Res. Analysis Workgroup Tidal Monitoring Analysis Workgroup March 9, 2007. Kathy Brohawn Technical & Regulatory Services Administration Maryland Department of Environment.

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Kathy Brohawn Technical & Regulatory Services Administration Maryland Department of Environment

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  1. Recreational Water Quality Standards, Bacteria Monitoring Chesapeake Bay ProgramLiving Res. Analysis WorkgroupTidal Monitoring Analysis Workgroup March 9, 2007

  2. Kathy Brohawn Technical & Regulatory Services Administration Maryland Department of Environment

  3. Who establishes bacteria guidelines? • Under the Clean Water Act, Maryland must adopt water quality standards • The US Environmental Protection Agency (EPA) is responsible for developing sound, scientifically defensible standards and guide lines that support state water quality programs • It is a public process that includes input from stake holders

  4. Who establishes bacteria guidelines? • Beaches Environmental Assessment and Coastal Health Act, 2000 • April 2000 - MDE promulgated interim water quality standards for bacteria allowing use of enterococcus and E. coli as indicator, but still allowing fecal coliform • April 2004 – MDE promulgated new regulations, adopting EPA’s 1986 criteria for bacteria for Enterococci and E. coli

  5. Why use “indicators” when monitoring bacteriological water quality? • Too many pathogens (bacteria:E. coli, Salmonella,shigella, vibrios; viruses: Norwalk, Polio, Hepatitis; Protozoa: cryptosporidium, giardia) • Dose/response is unknown and found in relatively small numbers in the environment • Lab methods expensive and lengthy

  6. Why use “indicators” when monitoring bacteriological water quality? • Provide evidence of recent fecal contamination from warm blooded animals • Used to screen for a large set of pathogens

  7. Characteristics of an Ideal Indicator Organism • Only present when human pathogens are present • Present in greater numbers than pathogens • Resistance to environmental conditions greater or the same as pathogens • Easily detected, counted, identified • Density of indicator related to known human health risk

  8. Characteristics of an Ideal Indicator Organism • Differentiates between micro flora of public health significance and those with little or no significance • Does not multiply in the environment • Applicable to all types of water bodies

  9. Assumptions • Indicators measured have the same (fecal) origin and therefore present the same public health risk • Indicators do not multiply in the environment • Indicators die off a the same rate as pathogens in the water column • Indicators are always from a fecal source

  10. Limitations of Indicator • E. Coli and Enterococci found in plant matter • Under certain conditions, can reproduce in the environment • Does not distinguish between human and non-human or non- fecal sources • Established bacteria limits assume bacteria measured is associated with human sewage

  11. Limitations of Criteria • Based on studies conducted in sewage contaminated waters • Measures relative risk to swimmers, not pollution • Observed relationship (densities of indicator : rates of illness) may not be valid if the size of the population contributing fecal wastes becomes too small or too large • Developed based on full exposure and head immersion

  12. Human Health Risk • Risk is greater if source is human vs. non-human • Risk is greater from poorly treated effluent from a sewage treatment plant vs. a few failing septic systems • Although we know there is a risk associated with wildlife and other non-human sources, we do not have the information available to measure it • Is there a risk if source is soil, decaying plant matter, or re-growth?

  13. Human Health Risk • Risk is greater for immuno-compromised individuals (elderly and very young) • Indicator levels are elevated following a rain event, which may increase risk • Swimming in natural waters is not risk free regardless of monitoring efforts for indicator bacteria

  14. Know the Source • Three most significant sources 1) combined sewers, 2)untreated waste water, 3)bather contamination • Wastes from pets, farm animals, and improper manure management from pastures or when spread on crop fields • Wildlife is a source of bacteria contamination to surface waters • Indicator bacteria can be found in decaying plant matter, soils, and sediments

  15. What do these numbers mean and what do we do about them? • Measure of health risk to swimmers, best understood with understanding of land based activities that could cause elevated bacteria levels in the water • Prevent sewer overflows • Maintain septic systems • Clean up after pets • Report poor manure management practices

  16. Shellfish Harvesting Waters • MDE is responsible for classifying shellfish harvesting waters in Maryland • Maryland and Virginia classify shellfish harvesting waters in the same way • National Shellfish Sanitation Program (NSSP), a national cooperative program to foster and promote shellfish sanitation through the cooperation of state and federal control agencies, the shellfish industry, and the academic community.

  17. Sanitary Survey Used to Classify Shellfish Harvesting Waters • Bacterial water quality monitoring • Indicator used for shellfish harvesting waters is fecal coliform or total coliform, US Food & Drug Administration • Identifying sources of potential and actual pollution • Hydrographic characteristics of shellfish harvesting areas • General land-use patterns

  18. References • Ambient Water Quality Criteria for Bacteria – 1986; US EPA 440/5-84-002 January 1986 http://www.epa.gov/waterscience/beaches/files/1986crit.pdf • Health Based Monitoring of Recreational Waters: The Feasibility of a New Approach (“The Annapolis Protocol”) The Outcome of Expert Consultation; Annapolis, USA Cosponsored by USEPA World Health Organization WHO/SDE/WSH/99.1 http://www.epa.gov/microbes/annapl.pdf • National Beach Guidance and Required Performance Criteria for Grants; US EPA-823-B-02-004: July 2002 http://www.epa.gov/waterscience/beaches/grants/guidance/all.pdf • Guide For The Control Of Molluscan Shellfishhttp://www.cfsan.fda.gov/~ear/nss2-toc.html

  19. Questions?

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