Could be fresh water, however the entire canal shore line will have this
thin crust. I often drive the So. Shore (SR106)early in the morning and see
this when the air temp is down in the 20s. Once the sun comes up and the
shadow of the have been eliminated, the ice goes away.

Steve
s/v Good Intentions


"Gordon" wrote in message
...
That crust of ice is probably fresh water lying on top of the salt
water.
Is there a creek or river entering the canal near your moorage? I've seen
that inside the marina at Pt Angeles.
Gordon