Surface Tension, Meg McKinlay (Walker)
The day that I was born, they drowned my town.
The town of Old Lower Grange was flooded to become a catchment on the day that Cassie was born. The town's Mayor pulled a lever, let the water in, and now all their houses are at the bottom of a lake and they all live in New Lower Grange in new houses that look just like the old ones.
Cassie is twelve now and she has to swim laps of the pool every day to help her lungs, which didn't develop properly on account of being born too early. One day, sick of swimming in the town pool (after a particularly disgusting "seven-bandaid swim") she goes down to the lake, to a spot that no one goes to - so she can swim in peace.
Liam, about the same age as Cassie and with a past that also distances him a little from people in their town, joins her at the lake and the two of them form a fast friendship and act as sounding boards for one another's theories when strange truths start to appear from the murky depths.
For the water level is dropping - revealing dead trees, forgotten objects and one humdinger of a mystery. Cassie is smart, she questions things, she has insight and listens to what isn't said - more so than any adult within these pages.
This is an eerie tale, a real page-turner and a wonderful read for anyone about ten and up.