In a 4 to 6 quart heavy pot, combine blueberries, the water, maple syrup, and lemon juice. Using a potato masher, slightly crush the blueberries. Bring to boiling, reduce heat. Simmer, covered, for about 5 minutes or until blueberries are tender, stirring occasionally.
Stir the sugar and currants into the blueberry mixture. Return to boiling, stirring until sugar dissolves, reduce heat. Simmer uncovered for about 30 minutes or until mixture thickens, stirring occasionally. Remove from heat. Stir in pecans and cinnamon.
Ladle hot conserve into hot, sterilized half-pint canning jars, leaving 1/4" headspace. Wipe rims, adjust lids. Process in boiling water canner for 10 minutes.
Make 5 half pints.