(NVR) - In the fourth year of drought, those who grow grapes in the Napa Valley say the vines are in pretty good shape.

Earlier this year, because of the early bud break, growers were concerned about the possibility of frost and having to use water from reservoirs to protect their vines. But there was no frost and, according to Silverado Vineyards’ Jon Emmerich, “We’re actually going into the growing season in pretty good shape,” with most reservoirs 80 to 90 percent full.

“A lot of us are reliant on wells. And unless you have a really shallow well, you’re probably going to be OK, because you’re not going to be tapping out,” he added.

Emmerich farms 400 acres throughout the Napa Valley, from Yountville to Carneros and from Soda Canyon down to Coombsville. He said most of the vines are 15 to 25 years old and drip-irrigated. He added, though, that he is looking at fairly new technology developed and licensed from UC Davis called Tule, a crop water use monitoring system that measures actual evapotranspiration, or how much water evaporates from a vine.

“It will allow us to drill down and see how much water the vine needs as opposed to blanket watering, 6 gallons an hour or 8 gallons an hour,” he added.

According to TuleTechnologies.com, the cost is $1,500 per sensor for the growing season, and one sensor can remotely monitor up to 10 acres. About 170 sensors are available for the 2015 season, since 329 have been sold, the website states.

David Pearson from Opus One said, “I think we can’t help but be concerned about the drought. We have been unexpectedly fortunate in that we’ve had rain in a timely fashion. During this growing season, we’ve had 21 or 22 inches of rain, which is sufficient for the vines to get through this growing season in fine fashion.”

Everyone needs to be concerned with the larger drought issue, he said, but “in a localized current sense, we’re comfortable.”

Although grower and winemaker Aaron Pott said the drought is “grim and sad, we need some rain for sure,” he added, “The vines don’t know it’s the fourth year of drought.”

The soils were filled with rain “pretty much at the right times, so the vines aren’t thinking there’s a drought going on.” Although he irrigated the vines earlier this season, he has stopped and is waiting for the vines to produce grapes.

St. Helena vintner Chris Phelps said he’s not worried about the health of the vines. “You know what is reassuring to me? I’m out hiking a lot in the hills around here and the creeks are still running. It was the same thing last year.” He said that’s unusual to see during June, even in non-drought years.