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How often are the swimming beaches sampled?
Swimming beaches are sampled once a week from May through September. Generally, samples are collected every Tuesday.
Who does the water quality sampling at King County swimming beaches?
Environmental Specialists from the King County Department of Natural Resources Environmental Services Unit sample King County swimming beaches.
How are samples collected?
Samples are collected in swimming areas where the water depths are approximately 1 meter (approximately 3 feet). All samples are collected in sterile 1 Liter wide mouth high-density polyethylene bottles, labeled for each sampling location. Care is taken to prevent contaminating the sample by washing hands before sampling, keeping fingers out of the inside of sample bottle, and inverting the sample bottle while scooping away from the person collecting the sample. At 1 location per sample run, a field duplicate sample is collected for quality control. Samples are preserved on ice in coolers during transport to the environmental laboratory.
What swimming beaches are tested?
The swimming beaches selected for this survey are public swimming beaches with officially designated swimming areas. These beaches were selected to provide a wide geographic coverage of beaches in lakes Sammamish and Washington, with Green Lake providing a small lake comparison.
Luther Burbank Park (King County), Idylwood Park (Redmond), Lake Sammamish State Park, Meydenbauer Bay (Bellevue), Juanita Beach (Kirkland), Newcastle Park (Bellevue), Andrew's Bay Beach/Seward Park (Seattle), Madison Park (Seattle), Matthews Beach (Seattle), Medina Park (Medina), Mt. Baker Park (Seattle), Yarrow Bay Park (Town of Yarrow Point), Magnuson Park, Sand Point (Seattle), West Green Lake (Seattle), Gene Coulon Park (Renton), Madrona Park (Seattle), and Pritchard Island Beach (Seattle).
Who analyzes the water quality samples from King County swimming beaches?
Samples are analyzed at the King County Environmental Laboratory. Microbiologists analyze the samples within hours of sample collection and can determine fecal coliform results in 24 hours.
What are fecal coliforms?
Fecal coliforms are intestinal bacteria that are routinely used as an indicator of sewage pollution in water, and as an indicator of the human health risk. Fecal coliform bacteria always occur at very high counts (several thousand CFU's) when sewage is present in the water; an example is when a sewer line breaks. However, high bacteria counts in water do not necessarily indicate human sewage pollution because many other mammals and birds also contribute to this type of bacteria. Low counts of fecal coliform bacteria, less than 50 CFU’s, are routinely found in high quality water. Typical fecal coliform bacteria counts from the middle of lakes Washington and Sammamish during the summer are less than 20 CFU's.
What is a CFU/100mL?
CFU’s are a unit of measure and stand for Colony Forming Units. After incubation, bluish colonies of bacteria should appear on the sample dish. It is then necessary to count all of the colonies that are in each dish. A calculation must be performed to determine the number of colony forming units per 100 milliliters of sample.
What is the method being used to determine fecal coliform?
The method used at the King County Laboratory is Standard Method 9222 D, 17th edition ( Standard Methods for the Examination of Water and Wastewater)
Why don't we use the RNA test for routine sampling of the beaches?
A technique that has been used to identify the source of the fecal bacteria is to use the genetic material RNA (ribonucleic acid) from the bacteria. This provides information on the species of animal which added the bacteria to the water.
A 1993 study using this RNA method conducted in Piper's Creek in Seattle's Carkeek Park identified domestic cats as the major source of bacteria. Studies conducted at Juanita Beach in 1998, identified ducks and geese as the major source of fecal coliform pollution, with seagulls and dogs as secondary sources. The RNA tests are expensive and time consuming, taking weeks to obtain the data. While the results are valuable in designing our long term water quality protection programs, the results are not available fast enough to use this technique for routine monitoring of the beaches or the sewer system. The fecal coliform testing (without RNA analysis) takes less than 48 hours, allowing a much faster response to a potential problem.
What is the protocol for closing a swimming beach?
The state Department of Health has not developed pollution standards for bathing beaches. When asked by local health departments, the state has recommended use of one of two standards: 1. the fecal coliform standard developed by the federal Water Pollution Control Federation, which is a geometric mean of 200 fecal coliforms, with not more than 10% of the samples exceeding 400. 2. the ten state standard which is a geometric mean of 200 fecal coliforms with no single sample exceeding 1000.
There is no consistent approach among local health departments regarding when or if a beach is to be closed. Also, there is no consistent indicator or level of contamination used to signal the need for a closure action. Agencies may use total coliforms, fecal coliforms, or even alternatives such as E. coli and Enterococcus bacteria. Although the state Department of Health may be consulted, no standard protocol for closure of swimming beaches exists.
What is the standard used by King County to determine if a swimming beach should be closed?
The Ten State Standard.
What is the cause for high bacteria counts?
There may be multiple bacterial sources for high fecal coliform counts. Potential sewage spills are the highest concern because of the increased risk of transferring disease from a human source. Fecal contamination from waterfowl, dogs and cats, surface run-off from poorly drained grassy areas adjacent to the beach, high concentrations from nearby creeks, and poor water circulation in the swimming area may contribute to the high bacterial counts.
Who determines if a beach should be closed for swimming?
Municipal and King County Park Departments determine if their respective swimming beach facility should be closed.
Public Health - Seattle and King County advises local park departments on swimming beach closures related to health and safety concerns.
If a beach is closed, can my dog swim in the area?
Dogs should not be taken to public swimming beaches. There is a $500 fine for having dogs on public swimming beaches in Seattle. Also, pets are more likely to go into various types of water to swim and drink than people. This can increase their risk of getting sick because of their higher exposure; however, many animals have a higher degree of tolerance to water-borne viral and bacterial infections. The best thing to do as soon as the animal leaves the water is to wash the animal thoroughly with soap and rinse it very well. If your animal develops diarrhea you can initially treat it by withholding food. At this stage it would be wise to consult with your veterinarian about what to do next. Be aware that if your animal is quite young or old, it could be at higher risk. If the animal seems unusually ill, call your vet immediately.
What are the symptoms if I swim in a contaminated area?
Ingestion - If a person incidentally or accidentally swallows contaminated water, your risk of becoming sick would probably increase slightly over swallowing water outside the area of contamination. The degree of risk would depend on 1) the amount of water swallowed, and 2) general health of the person (healthy, sick, immuno-suppressed). Gastrointestinal distress is a common symptom.
Dermal - Your risk of becoming ill or getting infection from skin contact is likely very low. The skin provides a very good barrier against most common bacteria and viruses. Your risk would increase slightly if contaminated water comes in contact with the inner ear, eyes or cuts/abrasions. Any infections resulting from this type of exposure would likely be treatable. Swimmer’s Itch is a common symptom.
Who is responsible for cleaning up the goose poop in the park?
The parks department staff is responsible for cleaning the walkways, piers and floats.
Why are there so many geese at these county parks?
In recent years, non-migratory ducks and geese have been living the good life, protected and encouraged by human development in King County. These waterfowl love to feed on the succulent grasses of well-kept lawns, particularly the new growth shoots that sprout after mowing. With few natural enemies to keep their numbers in balance, geese and ducks can overpopulate and become a nuisance. Large flocks can compete with other species of waterfowl, overgraze lawns, and litter yards and docks with droppings and molted feathers. Their droppings pollute lakes with nutrients, and, to make matters worse, their intestines may contain a tiny parasite that can cause a condition known as "swimmer's itch."
Canada geese are protected by the International Migratory Bird Treaty Act and should not be harmed. However, these and other waterfowl can be discouraged by deterrents such as two-foot-high fences, large helium balloons, scarecrows, streamers or reflectors. Because geese and ducks are attracted to lawns or domestic grass growing along shorelines, a buffer of native vegetation between the water's edge and a home-owner's lawn will deter them. Most importantly, do not feed waterfowl-and discourage others from feeding them as well.
What is the role of Public Health - Seattle and King County?
Public Health - Seattle and King County determines the public health implications of the bacteria data collected from this program and conveys this information to elected officials, local park departments and the public.
What is the role of local Parks Departments?
The parks departments are responsible for the operation and maintenance of park facilities.
What is the Water Quality Standard for Fecal Coliform in Streams?
According to the Washington Water Quality Standards WAC 173-201A-030, freshwaters rated AA (extraordinary) shall not have fecal coliform levels exceeding 50 colonies/100 ml and not have more than 10% of all samples exceeding 100 colonies/100 ml (for Class A excellent - 100 colonies/100 ml and less than 10% of all samples exceeding 200 colonies/100 ml). These concentrations are often exceeded in urban streams in King County.
What are some best management practices (BMP’s) that King County is implementing to help keep swim beaches open this year?
If fewer geese spend less time at the parks, there will be fewer feces and the bacterial load will decrease. Goose control using trained dogs is occurring at some parks outside of the King County park system.
Park personnel and the King County Marine Patrol have replaced the practice of washing duck and geese feces off of the walkways and into the swimming area.
An option would be to spray geese feces with dilute hydrogen peroxide would kill bacteria and would photo-oxidize, posing little or no water quality threat.
Comparison data indicate lower bacterial counts at beaches on open shorelines and in areas where there is greater exchange of water. Beaches in more enclosed bays, or with streams from an urbanized watershed discharging into them tend to have higher bacterial counts.
At Juanita Beach pumps have been installed that increase the water circulation in the swimming area by bringing in cleaner water and pushing out the fecal coliform contaminated water.
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