If El Niño doesn’t help this Christmas, Nacimiento will

Even if El Niño fails to bring enough water this winter, at least four communities in San Luis Obispo County could get more than enough water from Nacimiento.

Many of us hope for a Christmas visit from El Niño. “El Niño” is Spanish for “the boy.” It can also mean “the Christ Child.” El Niño also refers to a warm weather system over the Pacific Ocean, which sometimes brings rain around Christmas and the potential for a wetter-than-normal winter.

“Nacimiento” is Spanish for “birth.” It can also mean a Nativity scene. And in this county, Nacimiento is also a highly productive reservoir northwest of Paso Robles. Its dam was built in 1957 by Monterey County to provide water to irrigate the fields of the Salinas Valley and to fend off saltwater intrusion.

In a high-stakes game too complicated to explain here, San Luis Obispo County won the right to 17,500 acre-feet of Nacimiento water each year. Then about 10 years ago, Atascadero, Paso Robles, San Luis Obispo and Templeton got together and borrowed a bunch of money to build a pipeline. It brings Nacimiento Lake water to each of them. Part of Cayucos later joined for a small share. The pipeline started delivering water in 2011.

Water from reservoirs is measured in acre-feet. An acre-foot equals 325,851 gallons. Someone estimated that’s enough for three single-family homes for one year. I doubt that’s true in Paso Robles, where we have many days over 100 degrees.

Anyhow, Paso Robles signed up for 4,000 acre-feet per year from the pipeline; Templeton, 250; Atascadero, 2,000; San Luis Obispo, 3,380; and Cayucos, 25. An additional 1,750 acre-feet were reserved for the Nacimiento Lake vicinity. That left 6,095 acre-feet untaken. It was offered for sale. Nobody wanted it. They would have had to reimburse the original partners for part of their pipeline construction costs.

Now we’re in the fourth year of a drought. Lawns have dried. Trees have died. But Nacimiento is still a respectable lake. (This week it held more than 77,000 acre-feet.) So, the pipeline partners decided to increase their ownership of the lake by dividing up the unclaimed water.

They’d already paid all the pipeline’s construction costs with bond money. Acquiring the rights to the remaining water would cost them almost nothing. Paso Robles signed up for 2,532 more acre-feet per year. Templeton will soon consider whether to sign on for 158 more. Atascadero has signed on for an added 1,263 acre-feet, and San Luis Obispo claimed 2,130 more.

They did the right thing. Nacimiento Lake has one of the most productive watersheds in this region. This county has the annual right to 17,500-acre-feet of Nacimiento water. Monterey County can’t touch any of it. That’s why I say, if El Niño doesn’t help this Christmas, Nacimiento will.

In the meantime, the Nacimiento pipeline partners might sell any unneeded water to nearby farmers. It could help reduce the overpumping from the Paso Robles groundwater basin.

This story was originally published October 1, 2015 at 3:23 PM with the headline "If El Niño doesn’t help this Christmas, Nacimiento will."