Erica beat me to it
Go to this link and select "picnic shelters" and you shouldnt have a problem from there. If not the contact info is also available on the site. http://www.edmondswa.gov/parks-recreation-departments/rental-facilities.html
You can call the number at the bottom part of this link, in the section for picnic shelters. Note that there's two rates, which is a $50 difference, depending on the day of your picnic. http://www.edmondswa.gov/parks-recreation-departments/rental-facilities.html
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