Water / Don't Water calculations in Interval watering vs. weekly watering


#1

How does the Water / Don’t Water decision tree due to rain calculation work? If the “amount of rainfall” greater than a certain threshold is triggered in the weekly watering scenario, does the Iro just skip watering for that week? What about subsequent weeks to an earlier period’s (week’s) large rain event?

Alternatively, how does the Iro handle Water / Don’t Water decision tree for lengthy watering intervals of (up to) 21 days? Particularly if the “amount of rainfall” threshold trigger occurs early, or late, in the interval period?


#2

@eganders‌ Currently we look at 1 day observed and 1 day predicted precipitation. If we don’t meet the threshold we also look at the last week’s worth of evapotranspiration (ET) data and if precipitation offsets ET, we also skip. This is helpful for significant rain events that happen more than one day in the past. We are working with a water expert on how to combine this with water budgeting and have one unified view.

We don’t currently look ahead to the next scheduled event, but it is very easy to do.

All of this is being looked at for one more pass at smart water optimization. We’ve learned a ton and have a very flexible system where by now we can do some really cool things with all of the data we have access to.

Hope this helps, let us know if you have any more feedback or thoughts.


#3

@franz; Rather than it being exactly a week, perhaps an easy short run adjustment could be to use the user selected interval period instead, whether 7 days, or the max 21 day interval, for prior period rain event lookback. As an option, you could then allow a user defined period of time if they didn’t want to go the full interval.


#4

@eganders – i use IFTTT to set the rain delay for the maximum of 1 week if it detects rain in the next day’s forecast. this ensures that on a rain event, an entire week is skipped. i only water my lawn once a week so looking at 1 day forward / backward, etc. does me no good.


#5

although I’ll be the first to admit my methodology has its holes. my watering day is wednesday. thursday is sunny. friday it rains. on wednesday it will check thursday’s forecast to see if it rains and since it’s sunny, the wednesday sprinkler schedule will run even though friday it rains :slight_smile: it would be cool if i could delay if the 7 day forecast has rain in it but wunderground ifttt doesn’t support that i don’t believe.