“But,” you might say, “if he developed Fremont, why is W Blewett Way in Queen Anne?”
As you can see in the map below, and in this plat he filed in 1888 of what is now Fremont and North Queen Anne before the Fremont Cut was dug, Ewing and Blewett Streets used to be part of both neighborhods. When they became separated, the names were left alone on the Queen Anne side; in Fremont, they were changed as follows: Kilbourne to N 36th Street, Blewett to N 35th Street, and Ewing to N 34th Street.
It’s not quite that simple, though — Blewett never reached quite as far as 13th Avenue W. What appears to have happened is that a name was needed when what is now W Blewett Way was created in 1907, and because the street to the south was still Ewing, Blewett presented itself as a natural choice. The rest of Blewett south of the canal was vacated over the years, so this is all that’s left of the name.
Today, W Blewett Way begins at the north end of 13th Avenue W and goes east just about ⅒ of a mile before it becomes a private driveway.