Environmental Impact Study (Septic Study) - Executive Summary 

Press Releases:
April 2013: Major study suggests efficiently run softeners do not hurt septic tank performance
June 2011: Study launched to look at softener effects on septics

Additional Resources:
Fill-in-the-Blank Monovalent/Divalent Cation Ratio Calculation Form
EPA Softener/Septic Factsheet
EPA Septic Smart Website
NOWRA/WQA Guidance Document
Softeners and Septic Performance Toolkit

Softened Water Benefits Study - Executive Summary

Energy Savings Study
This independent study tested devices fed with softened and unsoftened water under controlled laboratory conditions designed to accelerate the waterside scaling in the device and quantify the performance efficiency.

Detergent Savings Study
Laundry - Study investigated stain removal with varying levels of water hardness, detergent dose, and temperature.
Dishwasher - Study included tests for removing difficult soils and spot and film evaluation with varying levels of water hardness and detergent dose.

Press Releases:
March 2011: Studies show washing with softened water can significantly cut detergent use, energy consumption
April 2010: Independent study: Softeners among 'very best' household energy savers

Additional Resources:
Softened Water Benefits Study: New Reports Related to Detergent and More Energy Savings