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Beach Health: Safe to Swim? June 19, 2009 U. S. Department of the Interior U. S. Geological Survey Heather Morehead Maryland Department of the Environment
Maryland Beaches Program • In 2008, Maryland monitored 218 beaches (72 coastal, 146 noncoastal) • Administered by MDE; Responsibility for monitoring and public notification is delegated to the local health departments • Total of 23 counties and Baltimore City: 9 have coastal beaches, 9 have only non-coastal beaches (6 counties have no beaches)
History of Beach Regulations in Maryland • Historically Local Health Departments administered their own program, and there were no standard criteria or methodologies. • ~1999 – MDE promulgated interim water quality standards for bacteria • • Allowed use of old fecal coliform standard and/or use of EPA’s 1986 criteria for Enterococcus and E. coli April 2004 – MDE adopted EPA’s 1986 Ambient Water Quality Criteria for Bacteria for water contact recreation and protection • • Dropped fecal coliform as indicator and defined beaches Use of Enterococcus (fresh water or marine water) and E. coli (fresh water) as indicators
Monitoring and Notification Monitoring • Local Health Departments conduct sampling • Frequency depends on Tier of beach • Tier 1 – 1/week • Tier 2 – Every other week • Tier 3 – 1/month • The Tier is based on frequency and nature of use, proximity of pollution sources, and other factors which may affect water quality.
Monitoring and Notification Laboratory Analysis • 6 hour holding time • Laboratory has 2 hours to process samples • 24 -hour incubation period using Enterolert or Colilert • Laboratory reports results immediately to local health departments • Results are also sent to MDE
Monitoring and Notification • If criteria are exceeded or there is a known pollution source, LHDs post notification and notify MDE • Notification Tools: • Signs at beach • Maryland. Healthy. Beaches. com • Local Health Department website or Twitter. com • Phone/Hotline
Tools for Decision-Making Pollution source surveys • MDE and local health departments conduct sanitary surveys to identify sources of fecal indicator bacteria • Field personnel go house-to-house collecting information on waste disposal systems and other potential sources • When problem is identified, regulatory action is taken to mitigate the problem • Process has historically been conducted using the “clip board and paper” • New digital data collection system involves the use of field notebooks with integrated GPS/GIS capabilities
Tools for Decision-Making Pollution source surveys • MDE utilizes digital data collection system developed by Maryland Environmental Services to conduct shoreline surveys
Tools for Decision-Making Pollution source surveys • In this waterfront neighborhood there were 258 dogs recorded during a survey • In one month, these dogs deposit approx. 3 tons of dog waste • A simple educational program encouraging residents to pick up their dog’s waste might address this issue
Tools for Decision-Making Pollution source surveys During sanitary survey, field personnel found discharge pipe over creek near beach. During sanitary survey, field personnel found raw sewage from broken sewage pipe in community near beach.
Tools for Decision-Making Predictive modeling • MDE has worked with Maryland DNR, NOAA, and local health department to develop a predictive model at popular beach • Used water bacteria data and various water quality and weather parameters • Thus far, unable to develop a predictive model because there was no strong correlation between observed bacteria levels and measured parameters
Tools for Decision-Making Precipitation tracking • Maryland Beaches Program is working with NWS and MDE GIS staff to collect precipitation information at beaches. • Providing information in maps to local health departments to help them determine which beaches are sensitive to significant rain events
Issues • Educating the public about the weaknesses of fecal indicator bacteria is difficult because of the scientific complexity of the criteria in use: • Fecal indicator bacteria do not cause illness--they are just indicators of recent fecal pollution • Risk to human health from human sources may be higher than the risk from other sources • Studies have shown that fecal indicator bacteria, in the absence of human or animal sources, can thrive and grow in sediments. • Current monitoring and lab analysis for fecal bacteria do not distinguish between sources or indentify if they are from re-growth in sediments
Issues There is an inherent delay in getting laboratory analytical results for beach samples. Beaches can remain closed when they should be open while beach managers are waiting for samples results Conversely, beaches may be open when there should be an advisory Pollution source surveys at beaches help managers better understand monitoring results and protect swimmers Inland beaches are not funded by the BEACH Act
Issues Current bacteria criteria were developed in areas where there were known human sources of fecal pollution, and are inadequate to address non-point sources of bacteria. The majority of Maryland’s waters are not impacted by untreated sewage sources from failing infrastructure, combined storm/sewer systems, or failing septic systems. Fecal pollution at some beaches is primarily from nonpoint sources where there is no observable problem to mitigate or on which to take action.
Thoughts about Rapid Testing Methods • If a more rapid testing method is developed, the question of how frequently a beach should be sampled needs to be answered • Current molecular methods being considered present a problem because they can detect viable and non-viable indicators and pathogens (i. e. , pathogens or indicator bacteria that have been destroyed by sewage treatment disinfection or naturally by UV rays and time outside the host)
Thoughts about New Criteria • Support current direction of EPA and others that consider pollution source surveys an important tool in protecting public health at beaches • Support consideration given to determining how human health risk can be different depending on source (for example human vs. wildlife) • Support recognition and consideration given to studies which prove that indicator bacteria are sometimes present in the absence of pollution sources
Maryland Department of the Environment Science Services Administration Beaches Program Contacts: Kathy Brohawn 410 -537 -3608 [email protected] state. md. us Heather Morehead 410 -537 -3618 [email protected] state. md. us 1800 Washington Boulevard | Baltimore, MD 21230 -1718 410 -537 -3000 | TTY Users: 1 -800 -735 -2258 www. mde. state. md. us