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Juanita Beach was reopened on 08/05/2005 after fecal coliform levels met standards for three consecutive samplings.
Click here to see the current measurements.
Why was Juanita Beach closed?
The routine fecal coliform bacteria sampling on July 26 was 1000 colony forming units per 100 milliliters of waster (cfu/100 ml). Beaches are closed when a single sample of >1000 cfu/100ml is collected. After a beach is closed three samples are collected across the beach. Re-sampling done on July 28 resulted in bacteria counts of 1800 cfu/100ml on the east end of the beach, 1200 cfu/100 ml in the middle (routine) sampling site, and 70 cfu/100ml at the west end of the beach. A similar pattern was observed in the e. coli data.
What is the source of the bacteria at this beach?
At Juanita Beach we usually suspect the urban runoff that enters adjacent to the beach from Juanita Creek. The bacteria sample collected in Juanita Creek on July 26 was 120 cfu/100ml, and on July 28 was 255 cfu/100ml, and it hasn’t rain in the past several days (we typically see elevated bacteria in several of our urban streams after rainstorms). The creek is also located along the western edge of the swimming areas, which had the lowest bacteria counts collected on July 28. While we do get periodic inputs to the swimming area from Juanita Creek, it doesn’t look like Juanita Creek was the source of the bacteria responsible for the recent closure.
Kirkland Parks Department has reported a flock of about 100-150 Canada Geese that have been resident at the beach fro the past several days. The geese are currently molting which would tend to keep them much closer to the beach (as they cannot fly while molting). Maybe it’s the geese here.
What was the justification fro re-opening the beach?
Additional samples were collected on Friday July 29, and the first three days of August . All of the bacterial samples collected were < 1000 cfu/100 ml. If a beach achives standards for three subsequent samplings, the beach is re-opened. The bacteria levels at Juanita Beach continue to meet standards and the beach was opened on August 5. We will continue to monitor this beach on a weekly basis until mid-September.
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