This book had so much promise it should have rated more than three stars, but the storytelling never truly engaged me and never seemed to take off.
For starters, there was a lot of complex time and space stuff at the heart of the story, which was essential to the plot, but which came across so garbled I only felt I grasped the broad gist of what was going on. That was OK for the most part, but when the ending depended on specific things that the canal turned out to be able to do, my reaction should have been "of course, I should have seen that coming." Instead it was "yeah, sure, if you say so."
I could have forgiven some feelings of Deus Ex Machina if the world and characters were truly engaging, but here is where it really fell down for me. Most of the action took place in one single, and very bare, location. The rest of the world was talked about, but never in a way that made it seem real. Even those scenes that took us away from the canal lacked any kind of depth. Some visual details were described, but the settings overall lacked any substance, and no real feeling or atmosphere. It was as if the characters were acting out their parts on an almost bare stage.
The characters themselves were mostly well drawn, but most of the time the only facial expression anyone seemed to manage was to smile.
All in all, everything came across to me as too distant to really grab me, pull me in, and make me care.