The NAACC database is available at https://naacc.org.
Both the "new" database (with data assessed with the new NAACC protocol) and the "old" database (with data older than July 2015 for crossings assessed with the old Massachusetts protocol) can be viewed there along with data contributed by other states using their own protocols.
Looking for NAACC Documents? Click here
Looking for Photographs to borrow? Click here