You can switch to an alternative means of water conditioning, such as an exchange tank water softening system. Some vendors offer non-salt treatment units for water conditioning.
The Sanitation District of Los Angeles County (LACSD) offers a listing of more than 50 alternative water conditioning systems. The site includes reviews from community members on the various products and services. The IEUA does not endorse any particular water conditioning unit, or provide any assurances regarding the effectiveness of any unit.