Capturing water data

Capturing water data

I'm aiming to put together a habitat map for our parish. I'll digitise data from surveys, DEFRA's MAGIC datasets and other sources to delineate woodland, hedgerows, grassland etc.
I want to include aquatic habitats such as rivers, streams, rhynes and ponds.
I could digitise by tracing (snapping) from the OS background but that would be a laborious process.
Any ideas on a better way?