Category Archives: Irrigation Water

No Relief In Sight For Parched West

Capital PressThe West is experiencing low stream flows but the summer dry season is far from over, so drought conditions are expected to become more severe.

Stream flows across the West are now running as low as they normally would in late summer, but autumn storms won’t be coming to the rescue anytime soon.

And neither did record rainfall in California last weekend.

With seasonal dry weather likely to continue over the next couple of months, experts say the area is facing extremely parched conditions barring an unlikely stretch of low temperatures and high precipitation.

“We’re expecting it to get worse. You’re going to see deterioration in the region,” said Dave Simeral, research meteorologist at the Western Regional Climate Center.

Given higher-than-normal temperatures over the past two months, streams and rivers are likely to heat up to the point of causing fish kills in some areas, he said.

Waterways should currently be receiving an infusion of cold water from melting snowpacks, but that snowfall was severely lacking last winter, Simeral said.

“You’re not getting that cool water being put into the system,” he said. “You saw a lot more rain than snow.”

Snowpacks melted up to 12 weeks earlier than normal in Oregon and rainfall was insufficient to support stream flows, said Scott Oviatt, the state’s snow survey supervisor for the USDA’s Natural Resources Conservation Service.

“It’s unprecedented, what we’ve been able to observe,” Oviatt said.

If the current trend continues, it’s likely that some streams will completely dry out over the summer, he said.

For agriculture, that has meant senior water rights holders have “called” water up to a month and a half earlier than average, effectively cutting off irrigation for junior water rights holders, according to the Oregon Water Resources Department.

Some growers are trying to direct water toward higher-value crops like onions and potatoes at the expense of irrigating their hay, said Oviatt.

“A lot of hard decisions are coming into play,” he said.

The problem isn’t limited to surface water, as groundwater levels are also depleted, he said.

Low soil moisture must be replenished with steady rains, as heavy but short-lived storms fail to fully penetrate the ground, Oviatt said.

“To build that back up, it will take significant and slow precipitation events,” he said.

Washington is facing a similar scenario, as 80 percent of its streams and rivers are below normal or at historic low flows, said Dan Partridge, communications manager for the Washington Department of Ecology’s water resources program.

The current situation is worse than in 2005, which was Washington’s last statewide drought, he said.

The potential for significant streams to run dry is “most certainly a possibility,” which raises concerns about fish passage and mortality, Partridge said.

In California, state wildlife managers have been conducting “rescues” in which they manually remove fish from shallow pools and move them to better habitats, said Jeanine Jones, interstate resources manager for the California Department of Water Resources.

Recent rainstorms that flooded Southern California haven’t provided much help in terms of irrigation, she said. “A lot of it ran off right away.”

With stream flows “way low,” farmers are expecting to idle roughly half a million of the state’s nine million irrigated acres, said Jones.

Roughly 75 percent of the precipitation in California occurs between November and March, so any eventual reprieve from the drought isn’t likely to come soon, she said.

“We’ve got a long ways to go before we see any real activity on that front,” she said.

Idaho is also dealing with low stream flows but farmers had anticipated even worse conditions earlier in the year, said Liz Cresto, hydrology section supervisor for the Idaho Water Resources Department.

Irrigators are worried about the low water carryover in reservoirs that will be available for 2016, but this year, spring rains delayed the need for stored water use, Cresto said.

“We’ve been able to stretch the season more,” she said.

Ways For Growers To Maximize Irrigation Water

Growing Produce. 4 November 2014.   Dire. That is just one of many terms being used to describe the drought situation in California. As water, or the lack thereof, is a focal point in the state, managing this precious resource is critical for those producing high-value crops such as vegetables.According to The National Drought Mitigation Center, as of Sept. 28, 70% of California’s rangeland and pastures were rated to be in very poor to poor condition. It isn’t just California that is facing this issue. The report states that Oregon, Nevada, Washington, New Mexico, and Texas are also dealing with drought affected areas. Continue reading Ways For Growers To Maximize Irrigation Water

Efficient Nitrogen Use in Walnuts Tied to Irrigation Management

Western Farm Press. 17 March 2014.   Protecting groundwater quality from nitrate contamination when fertilizing walnut trees requires being on top of your game in managing not only your nitrogen applications but also your irrigation system.

The goal is to allocate your total N budget through the season so that you feed the trees only the amount of N they need and only when they need it, explains Allan Fulton, University of California Cooperative Extension irrigation and water resources advisor for Tehama County. 

Previous research suggests that about 20 pounds of N per 1,000 pounds of dry in-shell walnuts may be exported from an orchard at harvest, he notes. Because these studies of N use by walnut were conducted more than two decades ago, researchers are now doubling checking this rule of thumb for modern walnut varieties.

Apply too much N or put it on at the wrong time and unused portions of the nutrient can leach out of the root zone in the form of nitrate, threatening groundwater quality.

The depth of the root zone depends on the age of the walnut tree and soil characteristics. In uniform, loose soils, mature walnut trees may sink their roots as deep 8 to 10 feet into the ground. In layered, compacted soils, these roots may be able to push no deeper than about 3 to 5 feet, Fulton reports.

“The younger, finer roots that take up nutrients most efficiently are usually found in top 3 feet or so of the soil profile,” he says. “The deeper roots are not as dense and are more involved with taking up water and anchoring the tree than taking up nutrients.”

Even if your timing and rate of nitrogen application is optimum, an inefficient irrigation system can still put ground water quality and your profits at risk. Consider the case where faulty emitters are applying more water in some areas of your orchard than your trees need, causing the excess N to leach out.

“Then, you’ve set yourself up for a double whammy,” Fulton says. “If you’ve limited nitrogen applications to no more than the crop needs, but you lose some to leaching, you can add nitrates to groundwater. Plus, the trees won’t get all the nitrogen they need for proper growth and nut production.”

Timing of your N applications should coincide with the trees’ nutrient needs, he notes. University of California research shows that prior to bud break, walnut trees draw N from reserves stored in the tree from the previous season and not from fertilizer applied to the soil in the current season. So, rather than risk the loss of any N applied during dormancy or near bud break, Fulton recommends waiting to make the first N application until after bloom is complete. read more


Western Farm Press. 17 March 2014.  Salinity and scarcity of water were very much in the spotlight at the 2014 California Plant and Soil Conference in Fresno.

Multiple speakers showed pictures of what they labeled “California snow,” salt that had precipitated out atop soil where trees and other crops fight to grow.

They painted a grim picture of a year in which sparse winter rains have done little to drive toxic minerals deeper, away from plant roots. They said an expected lack of available water will take away one of the weapons growers can use to combat the toxins.

But they also talked of water management and steps growers are taking to find salt-tolerant crops or varieties and research on just how “tough” some crops can be.

Among those looking for crops that can survive the less than friendly soils on the Central Valley’s west side is Gary Banuelos, a researcher with the Agricultural Research Service in Parlier.

Banuelos said the villain is not simply limited to salts. Also included as potentially toxic are selenium and boron. He talked of alternate crops for high salt and boron conditions.

Leaching in tiled fields has been one way of coping with the toxins, he said. But leaching boron out of the root ball requires three times the amount of water than that required to leach salt.

“It can be done with water, but it’s almost non-existent (this year),” Banuelos said. “That’s why a lot of land is fallow.”

Banuelos has been looking for plants that can grow in toxic soils, including some varieties of poplars for biomass to generate electricity, cacti with fruit that can be used in juice and other products, grasses that may be blended into cattle feed, mustard, broccoli, safflower and other plants.

“We’re always looking to at least being able to earn between $1,000 and $1,500 an acre or otherwise the crop will not even be considered,” he said.

Others who addressed the conference included:

• Rick Snyder, with UC Davis Cooperative Extension, who had some advice on evapotranspiration-based scheduling during a drought.

He said producers need to take into account fog, morning dew, solar radiation or light interception by the foliage and other factors.

Applying less water will reduce deep percolation, he said, but it could result in higher salinity with the rooting zone so that eventually, deficit irrigation will become more problematic, especially if practiced over a long term drought.

He said producers may want to sort out a percentage of irrigation availability that will still bring profit, idling some land if necessary to assure they have a percentage they can apply to achieve that goal.

In some cases, he said, it might be better to reduce the area planted and apply more water to smaller cropped area to maintain higher production.

If water supplies are inadequate, Snyder said, it is best to irrigate orchards and vines at about the same frequency as in non-drought years, but apply less water per irrigation.  read more


Wall Street Journal. 18 October 2012. Few people in the world are more water-conscious than California farmers.

The state leads the nation in farm revenue and produces nearly half of the domestic supply of fruits, nuts and vegetables. It also boasts nine of the top 10 producing counties in the nation, according to the California Department of Food and Agriculture.

Yet California is one of the driest states in the U.S., getting an average of just 22 inches of precipitation annually compared with more than 40 inches for states like Missouri and New York. And, with nearly 40 million people, California is also the most populous state—meaning there’s a lot of competition for that precious rain and snow.

How do the farmers make do with so little water? They use technology and the state’s topography to stretch existing supplies as far as they can.


100-ppm of anything in irrigation water amounts to 270 lbs. per acre-foot of water.  Example:  A bicarbonate level of 250-ppm (very common in California and other parts of the world) delivers 675 lbs. of bicarbonate per acre foot of water.  Many crops may need 2.5 acre-feet of water, so a grower could deliver a surprising 1,688 lbs. of bicarbonate per acre into the soil each year.  Each pound of bicarbonate ties up one pound of soluble calcium.


Western Farm Press.  21 March 2012. A recent U.C. Davis study about nitrate contamination in underground water supplies throughout California’s Central Valley and the Salinas Valley revealed that agricultural fertilizers were principally responsible for the contamination. However, the general public may not realize that the problem of nitrates draining into drinking water tables has been a complex issue that agriculture has been tackling for many years.

Regarding the U.C. Davis study highlighting the problem, the fertilizer industry acknowledges the importance of dealing with the problem of nitrates seeping into California’s groundwater, and the industry has not been sitting idly by and not doing anything about it.

Granted, the new study did note the scope of the problem and the numbers of those people affected by nitrate pollution, along with pointing out financial remedies to deal with the situation, but general readers might not know that the industry has been working hand-in-glove with agriculture and state agencies to reduce nitrate loads on croplands.

It is even accurate to state that had it not been for the research and education funded by the fertilizer industry and the improved farming practices over the last many years to deal with the nitrate issue, UC Davis researchers may have reported numbers that greatly exceeded their findings about the extent of the problem and the amount of those residents impacted. To put the nitrate issue into context, it should be pointed out that during the past 30 years the fertilizer industry in California has self-funded research on the issue working in tandem with the California Department of Food and Agriculture.

More specifically, CDFA’s Fertilizer Research and Education Program (FREP) has concentrated on developing extensive “best management practices (BMPs)” to mitigate contributions from fertilizers. Over the years, with the support of the fertilizer industry, CDFA/FREP has contributed millions of dollars in grant funds to combat the nitrate problem. Through nutrient management projects, farmers are implementing BMPs that optimize the efficiency of fertilizer usage by matching nutrient supply with crop requirements and to minimize nutrient loses. read more

Water Usage Report for California Growers

Central Valley Business Times.  16 November 2011.  Farmers have nearly exhausted conservation methods of agricultural use of irrigation water in the Central Valley, concludes a report from Fresno State Wednesday that was paid for at least in part by water interests.  The report by the Center for Irrigation Technology at California State University, Fresno, says that claims that California farmers are wasteful and inefficient in managing their water supplies are inaccurate.  Funding for the report was provided by the U.S. Bureau of Reclamation and the California Farm Water Coalition.


The report is based on a thorough review of published research and technical data as well as state of California publications to assess the overall potential for agricultural water-use efficiency to provide new water supplies, the university says. The authors of say they did no original research for the report.  They conclude that little potential exists for new water unless large swaths of agricultural land are taken out of production, which technically is not water-use efficiency.  The study is an important addition to the ongoing discussions about California water and specifically what decisions must be made to assure adequate supplies for the future.  read more


Current Sierra Nevada Snowpack Report

SACRAMENTO. 24 February 2011  — The Department of Water Resources (DWR) will conduct its third manual snow survey of the winter at 11 a.m., Tuesday, March 1, 2011, near Echo Summit on Highway 50, not far from Lake Tahoe.  Currently, electronic readings reflect an increase in snowpack water content for this month. The water content is at 100 percent of the April 1 seasonal average, with an increase of 6 inches from February 1.

After a wet December, conditions were unusually dry during January and the first half of February. Then a week of storms delivered almost normal amounts for the month, offsetting the deficiency of the first two weeks. The statewide precipitation for January was about 30 percent of average. “We are hopeful March will help improve our water supply, especially with the upcoming weather predictions,” said DWR Director Mark Cowin. “With our ever-changing weather conditions, as well as delivery restrictions, conservation will continue to remain as a top priority.”

Manual surveys are conducted up and down the state’s mountain ranges on or about the first of the winter months. The manual surveys supplement and provide accuracy checks to real-time electronic readings as the snowpack builds, then melts in early spring and summer. April 1 is when snowpack water content normally is at its peak before the spring runoff.

The State Water Project (SWP) delivers water to more than 25 million Californians and nearly a million acres of irrigated farmland. The mountain snowpack provides approximately one-third of the water for California’s households, industry and farms as it slowly melts into streams and reservoirs. DWR estimates it will be able to deliver 60 percent of requested SWP water this year. The estimate will be adjusted as hydrologic and regulatory conditions continue to develop. 

Soil Structure Problems

Tokay Grapes, west of Lodi, California

Sorry, I can’t help it…  I see water penetration problems due to poor soil structure wherever I go and I have to stop and take pictures…. and the problem has certainly gotting worse and worse in recent years. 

I stopped a took this photo last week [Friday 23 April 2010] after a light rain.  The soil is very sandy… probably a sandy loam, but after just a light rain, the water is standing in the lower areas.  This condition is very indicitive of poor soil structure from using snow-melt water for years, which has led to this serious problem.  Not only does the water not move down into the soil well, oxygen can’t move into the soil very well, and of course, the root system is suffering, too.  If you have any problems with your crops like this, contact us… we can help improve your production and profit.  Like the Men’s Wearhouse guy, we guanantee it…   Dr. B.