Acquia Desktop & MAMP: No Drupal site found, only 'drush' cache was cleared
To fix this answer I created a new Alias called adrush which points to the Acquia DevDesktop Version. 

In my .bash_profile file in my home directory I added 

alias adrush='/Applications/DevDesktop/drush/drush'

now when running drush commands for sites that are in my Acquia DevDesktop environment I enter adrush cc all