The Prince and the Troll by Rainbow Rowell

This is how fairy tales really should be told.  In this case a man, who lives by a road and loves his job, crosses a bridge every day.  The problem is that building the road has caused the river under the bridge to silt-up and instead of clear water, there is just a lot of mud.  One day, when he has stopped to look at the river, he drops his phone.  But it is caught by the bridge troll.  She manages to toss the phone back up to him.  Over time, he builds up a friendly relationship with her, finding a way to get down near her and bring a cup of coffee each day from her from Starbucks.  He falls in love with her, but she is wiser than he is and knows nothing good can come from such a relationship.  Eventually it rains a lot and the river flows once again, sweeping everything in its path away, including the troll.  But in spite of this the man continues to stop each day at the bridge, waiting for her return.