The only option I believe you have is to ride on 2" tires (minimum), so when you bump the edge of the road at times (and you will), that you will stay stable. Get a fiberglass whip antenna about $10. Mount a Pool Noodle that sticks out horizontally from the side of the bike towards traffic ($1). Mount lights on each. (5 to $20) Get a GoPro camera to record all traffic coming up on you. (used older models are reasonable). Then take 1/3 of the paved surface to ride safely. When drivers act aggressive show the vids to the appropriate authorities. Is it only 1.7 miles? Come on man. Trust me when I say that you will need to learn these skills if you are going to ever get off "your" bike path. If you want some nightmares try the Astoria bridge at rush hour in a big ass storm.