An atmospheric river has deluged the region, leaving sodden fields and broken hillsides in its wake. I've emerged will little damage. The roof rain gutter feeding my cisterns fed more water than my overflow drain could handle, creating an undesirable four inch pool of standing water against my house. My only real-time option was to attach a hose to the drain valve and give up the water I'd planned to water with later in the year.
There will need to be a long-term solution as well, of course. But isn't that how we get by with life's disturbances? Implement the best accommodating solution to move past the problem for now, then reassess later for a longer-term plan. Distributed distribution of the inflow? More generous overflow capability? Eliminate the cisterns all together? We buy ourselves time, hopefully with little or no irrecoverable damage.
The photograph shows my arrangement. The guttered cistern sits a few inches higher than the other. The roof gutter output flows into one cistern, who's bottom output feeds the bottom of the other, such that they fill equally. The upper spigot on the second feeds the overflow hose that is sunk under the rocks to the sidewalk. The brighter green hose with a hose bin is my temporary addition that stopped water from spilling over the cistern top and flooded the planter area.
The purpose of this arrangement is to trap winter rain water for my front yard plants. They are native plants, shrubs and tree that thrive in our Mediterranean climate. Their common characteristic is getting the majority of their water need from the atmosphere, and not the ground. The leaves, harder and more reflective on the top than the bottom, are shaped to funnel water down their stems. It is why they will regrow after fire, so long as their root structure was undisturbed.
After a first year of maturation, my plantings get a deep soak every three months, with some nutrients added. Each fifty-five gallon cistern shown here is enough for one complete watering. With a nominal amount of rainfall, I'm able to go the year with just this. Combined with additional cisterns for my back yard plantings, my household water usage has dropped so low that I'm unaffected by the recent drought-driven water rationing mandates. A win-win all around.