SavingWater.org
This website is sponsored by the Saving Water Partnership, a group of local utilities that fund water conservation programs in Seattle and King County.

The Irrigation Water Management Society
Find watering calculators and real-time weather information for your irrigation system.

California Urban Water Conservation Council
This Web site features a "Product News" section with numerous studies on everything from toilets to irrigation. A few examples of the many studies include: Flapper Materials Durability, Testing of Popular Flushometer Valve/Bowl Combinations and After-Market Toilet Flappers: Compatibility and Flush Volumes. Also find the UNAR (Uniform North American Requirements) for toilet fixtures lists. UNAR encompasses two tiers of performance: conventional toilet fixtures flushing at 1.3 to 1.6 gallons (PDF, 62 kb) and HETs flushing at 1.28 gallons or less (PDF, 58 kb). SPU uses UNAR lists as their approved list for toilet rebates.

Connecting the Drops Toward Sustainable Water Strategies
Developed by the Global Environmental Management Initiative (GEMI), this site assists companies and other organizations to better understand what emerging water issues might mean for them, given their operations, needs and circumstances.

Rocky Mountain Institute - Water
Rocky Mountain's water efficiency page is a great place to view information on water efficiency policy and implementation, infrastructure and systems planning, commercial, industrial and institutional water efficiency and much more.

WaterWiser
Check out this water efficiency clearinghouse for articles, case studies, reference materials, papers and conference postings.