Iydlwood Beach Park

Managed by King County Department Natural Resources and Parks

Located on the shores of picturesque Lake Sammamish, Idylwood features a swimming beach, including a bathhouse and restrooms. Launch your car-top boat from the park’s small ramp. Spread out and play a game in the large open space or explore Idylwood’s playground area. Picnic shelters and picnic tables complete the picture for a perfect get-together. You will find plenty of parking here, as well.

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COVID-19

Keep your distance from other people.

Practicing social distancing is essential right now. Follow the advice of the health experts. If your community has asked that you remain indoors and away from others, do so. Heading to the beach should only be considered an option if social distancing practices can be followed. Spending a day in any crowded place is the worst thing we can do for our most vulnerable right now and will counter the efforts to curb the virus’ spread.

For more information, please visit the World Health Organization public resource on COVID-19.

Water Quality

Meets water quality standards
Current Status
This status is based on the latest sample, taken on May 26th, 2020. King County Department Natural Resources and Parks updates the status of this beach as soon as test results become available. These results were posted to Swim Guide on May 28th, 2020 at 6:43 PM.

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Current Weather

10°C

Clear and sunny

Report Pollution

Monitoring Frequency

Source Information

During the sampling period, Puget Soundkeeper Alliance regularly updates the Swim Guide to reflect the most current information. Local health officials use the following protocol to make closure determinations – A day’s average E. coli value is over 1000 CFU/100 mL – OR - The average of the E. coli values for the three most recent sampling days is over 200 CFU/100 mL. The three-day average is calculated using the geometric mean (geomean). The unit of measure is a CFU which stands for Colony Forming Units. A beach is marked Green (open) when both of these protocols are met. A beach is marked Red (closed) when these criteria are not met and the public health officials have closed the beach. A beach may also be marked Red if there is a Harmful Algal Bloom (HAB) reported at the beach. A beach is marked Grey when current water quality data is not available. The King County Water and Land Resources Division (WLRD) collects and analyzes the samples. Public Health Seattle & King County is alerted when bacteria or state algal toxin thresholds are exceeded and determines the health and safety implications of the bacteria and algal toxin data collected, and they work with King County WLRD and the local park manager to post an advisory. For more information go to King County Swimming Beach Bacteria Monitoring website: kingcounty.gov/swimbeach.

Water Quality Graph