Folks bellyaching about their lawns being less green in order to meet a state mandated 25 percent water use cutback may want to consider themselves lucky.

Mary Hildebrand has already lost 40 percent of her “lawn” to drought.

Hildebrand is among a relatively handful of Californians that hold one of the two oldest legally recognized water rights — riparian rights. She farms 100 acres southwest of Manteca near the San Joaquin River. Her “lawn” is actually farmland that she has had to fallow due to the river dropping so much that it made pumping water futile along the slough that has provided water to grow crops for more than a century. The land that is not fallow is planted in asparagus.

She’s also a member of the South Delta Water Agency board of directors.

And perhaps more important being part of what should be the strongest water users in terms of rights besides point of origin Hildebrand is among the weakest in terms of numbers standing up to others from urban users to farms in the south San Joaquin Valley that import massive amounts of water. As such she has to be an astute student of water policy rights and politics in order to assure her survival as a farmer.

“The water that (riparian irrigators use) doesn’t disappear,” Hildebrand said from her kitchen table in her home perched atop a levee. “It is returned to the river.”

It is why claims last week by the Metropolitan Water District serving the Los Angeles Basin complaining that “massive amounts of water” were mysteriously disappearing as it snaked its way through Delta waterways before reaching the pumps at Tracy and inferring riparian water users were “stealing” it are easily shot down.

Hildebrand noted the water farmers take from the river and apply to crops almost all returns via runoff or percolation save for what little is lost to evaporation and “consumptive use” by the crops being grown. That’s because riverside water tables are so high, that the water that soaks into the ground is returned to the river within a matter of days.

Also water levels never drop in the Delta. If fresh water isn’t flowing through in adequate amounts seawater from the San Francisco Bay takes its place. It is why the state is moving forward with a $28 million emergency rock barrier across part of the Delta.

“It is why the issue at Vernalis is water quality,” Hildebrand said of a point near the confluence of the Stanislaus and San Joaquin rivers just a few miles south of her farm that place a pivotal role in California water politics.

At the same time there are no more farming operations in the Delta than there was a century ago as land farmed with water secured through riparian water rights is not expanding.

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Pressurized systems don’t create new water

Hildebrand also has a different view of the proposal to pressurize the entire South San Joaquin Irrigation District system as was done with Division 9 near her farm. The plan is to finance the $175 million project using the sale of estimated 75,000 acre feet of water that the project would reduce needing to be applied to crops and orchards.

She said if a hypothetical district had 500 acre feet of water and diverted 100 acre feet of water to crops and had a consumptive use of 75 acre feet that would return 25 acre feet to the river sending 425 acre feet downstream.

If a pressurized delivery system reduced the water diverted to farming to 75 acre feet with all it going to consumptive use to grow food, there would still be 425 acre feet sent downstream in the river.

In other words water that soaks into the ground and is not consumed by crops or evaporates ultimately continues its journey whether it is in a river or underground aquifer of which both are connected.

The hypothetical district may have an extra 25 acre feet to sell by more efficient delivery in its own district but is 25 acre feet that would have made its way back into the river and aquifer without pressurization.

“There is no new water to sell,” Hildebrand said.

That doesn’t mean pressurization isn’t a good thing. She’s talked to nearby Division 9 farmers who report using less water while seeing crop yields increase significantly.

Also by switching SSJID farmers from flood irrigation and even sprinklers, Hildebrand said it will have a significant impact on the aquifer serving the region.

The SSJID has conceded that is a legitimate question that must be addressed in environmental studies since the district has effectively been recharging area aquifers for a century using surface water from the Stanislaus River watershed. That would have an impact on farmers that use wells exclusively, domestic rural wells plus nearby cities.

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Only source of “new” water is in coastal cities

And while Hildebrand believes any effort by Manteca to recycle water does some good, it doesn’t create new water.

That’s because the treated wastewater Manteca current releases into the San Joaquin River is used by others whether its Delta farmers or Southern California urban residents via the California Aqueduct before it ultimately ends up in the Pacific Ocean.

It explains why she views San Francisco’s as one of the state’s wanton water wasters despite the fact the city’s residents consume 98 gallons of water per capita each day compared to the state average of 196 gallons.

“All they do is treat wastewater and then dump it into the ocean,” Hildebrand noted.

No one else in California will use that water.

Hildebrand said new California water will only be generated through developing desalinization plants and wastewater recycling plans in coastal cities.

She noted if Manteca recycled wastewater it would reduce surface and ground water they need but it would essentially take water away from downstream users.

“It’s good for the city to do but it doesn’t really create new water for California,” Hildebrand said.

One thing she believes needs to be done to give people a better understanding of water uses among various competing interests in California is for everyone to grasp the fact that studies show it takes a third of an acre foot of water to grow the food a typical person consumes in a year.

She noted it might make them think twice before complaining about how their lawns will have to be less green this year.