The bitcoin cash (BCH) hard fork was created on August 1st, at bitcoin block #478558. If you had bitcoin in your wallet at the time of the BCH fork then you can enable BCH within your Blockchain wallet. This can be done by clicking on Settings and then General. Show Bitcoin Cash Balance will be listed at the bottom of this section.
The following message will be displayed. Please read over it carefully:
Click on See Bitcoin Cash Balance to view the balance of BCH in your wallet. Any accounts with BCH will be listed.
Please note: if you did not have any bitcoin/BCH in your wallet at the time of fork then this option will not be available. The Blockchain.info wallet is not a true BCH wallet. We are only making these funds available within our wallet to users who had bitcoin/BCH at the time of the fork.