Yes, the EPA Watersense Water Budget Tool can be used for v2009 BD+C and O+M projects. The thresholds in v2009 must still be documented; there is no v4 substitute. The v2009 controller efficiency criteria still holds (e.g. controller efficiency savings are limited to 30%).
EBOM Option 1: projects can use the theoretical calculation from Option 2 to establish the baseline for Option 1. The theoretical baseline case should be calculated using the month of July or the month with the highest irrigation demand and must be compared to metered water use data from that same month. Average values must be used for plant species, density and microclimate factor.
EBOM Option 2: percentage savings can be documented using the Water Budget Tool in place of the theoretical calculations.
EBOM Option 3: the Water Budget Tool can be considered an independent irrigation performance tool. Compare the project's metered water use against the baseline, not the landscape water allowance (LWA).