Seems like we’re already a couple months into 2019, right?
In terms of calendar year, the answer is “yes.”
|Diagram showing the relationship|
between calendar and water years
But in terms of water year,
We are only now approaching the start of Water Year 2019.
The reason is semi-explained in the diagram above.
The six month summer span (May-Oct) marks our reliably rainy half of the year whereas the six month winter span (Nov-Apr) marks the time when rains are the exception, not the rule. October and May are actually “shoulder seasons.” They can go either way. And of course all it takes is one big storm front in any winter month to significantly refill the swamp.
In terms hydro bookkeeping, May 1st marks the calendar day for starting the water year anew.