EPA WaterSense testing of irrigation controllers and sprinkler timers is the WRONG standard for water conservation.
The IA SWAT testing of weather based irrigation controllers is the wrong standard for people interested in water conservation. The nearly identical score shown below shows that IA SWAT testing is meaningless. Click on this link and read the complete adoption of IA SWAT into the WaterSense standard. The IA SWAT protocol is 70% of the EPA's spec on Watersense testing of irrigation controllers. WaterSense is the wrong standard for people interested in water conservation for the same reasons that IA SWAT is wrong:

These reasons are why Accurate WeatherSet has NOT submitted its controllers for EPA WaterSense testing.

With these "for the manufacturers standards," note that nearly all manufacturers of irrigation controllers scored 100% on Irrigation Adequacy. With these "for the manufacturers standards," nearly all irrigation controllers scored 0% on Irrigation Excess or overwatered. Hunter with their solar sync and Toro's and Irritrol's copy of Hunter's solar synce all overwater even over this short 30-day interval.These nearly uniform scores and extremely short testing interval make the EPA WaterSense testing of irrigation controllerss useless when judging irrigation controllerss for water conservation.

IA SWAT testing results shown

The EPA should have used "standards set by water districts" with the purpose of establishing water conservation by manufacture of irrigation controllers and sprinkler timers in the Evaluation of California Smart Controllers Program which was funded by the people of California. Millions of dollars went to water districts to subsize the installation of 1000s of irrigation controllers and sprinkler timers. After the data was presented in first draft, the participating water district criticized and requested additions to the report. After a year of requested changes, the data was presented in this final report. So this report is based on evidence. This Evaluation clearly shows wide variations in water savings that happen when these controllers are placed in the hands of the consumers and contractors, and opearted for over a year. The chart below is simplified from Table 56 on page 110 of that report and shows the field performance of many of the irrigation controllers and sprinkler timer listed above or their technologies.

Chart showing water savings from Evaluation

Below is another reasons why MWD and EBMUD should continue with their 309-page procedures to test and report on Weather Based Irrigation Controlllers. The newest sensors for Hunter and Toro are NOT tested with the procedures in the 309-page report. Look at the EPA WaterSense testing for the Hunter controllers, you will see that Hunter replaced their ET System in 2011 with their Solar Synce sensor. They made this replacement to reduce cost from the ET System sensor which cost $260 to the Solar Sync which sells for $65. Yet in the EPA WaterSense testing, the Hunter Solar Synce sensor over-watered by 12.2 % in 2011 while their ET System sensor over-watered only 2.3% in 2007. I would have expected the second test (Solar Sync) to be better than the first test. If you look at at the Toro and Irritrol Climate Logic sensor, you see the same degradation in EPA WaterSense test results when compared to to ET Everywhere, also done to reduce cost. Since Toro/Irritrol Climnate Logic add-on their existing controllers copied Hunter's add-on to its existing controllers, it seems they also copied the degradation in water conservation. You can see the Accurate WeatherSet was the first company to use ONLY local solar measurements for its controller. We have the most experience and best water savings.

Hunter and Toro's newest sensors NOT in 209 page report

California led the way in reducing auto emission and established a world-wide standard. It should do the same with irrigation controllers and sprinkler timers and become standard for testing and reporting on this most important remaining part of water conservation. Such evidence-based tests will supplant EPA WaterSense and be used nationally by the EPA for their WaterSense labeling.