The first one downstream is just below Thomas Eddy. It's private and you need to get a permit before going there. Below that your next stop is the Maple Street ramp in Snohomish. It's a crappy ramp, but usable except at low tides.

That is a looong drift. If you hit that area on an incoming tide and with the usual upstream wind you will get your exercise rowing.
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No huevos no pollo.