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Our View: No hard science? No sewer-fee hike!

What happens when Ventura County farmers want to grow something even more delicate?

Posted: June 26, 2010 2:39 p.m.
Updated: June 27, 2010 4:30 a.m.
 

Avocados. Strawberries. Flowers. Ventura County farmers say we’re killing their crops because we’re sending too much chloride — salt — down the Santa Clara River.

Are we?

We know what the politicians say.

The governor-appointed members of L.A.’s Regional Water Quality Control Board, who kowtow to the downstream farmers, say we must reduce our chloride discharges to 117 milligrams per liter of water — or else.

Or else they can levy fines up to $10,000 for every day we’re out of compliance.

The other set of affected politicians — the city and county officials who serve on the SCV Sanitation District board — are freaking out.

Under state law, they’ve got no choice but to comply with whatever the Water Quality Control Board says. They’ve got to suck enough salt out of the water to hit the 117-milligrams-per-liter mark, even if it means they must hike every homeowner’s sewer fees to pay for new water treatment facilities.

The political repercussions of hiking sewer fees could be immense.

But their backs are against the wall.

Given the debate that’s raging, one would expect science to conclusively prove that avocados, strawberries and nursery plants start to wither and die if their water contains more than 117 mg/l of chloride.

Right?

Wrong.

Science doesn’t say that at all.

In the 1990s, the Water Quality Control Board limited our sanitation districts’ chloride discharges to 190 milligrams per liter.
Ventura County farmers thought that was too high, so the Water Quality Control Board conducted a three-year study and brought the limit down to 100 mg/l.

It was an impossible target. During drought conditions, when there isn’t enough water to push salt deeply enough into the soil, we were barely meeting the 190 ppm mandate.

Turns out, the “science” didn’t support the 100 ppm level. The only “science” the Water Quality Control Board conducted was a peer review of studies done elsewhere, dating back to the 1960s.

According to the sanitation districts in 1999, “the 100 mg/l value is the result of an incorrectly interpreted reference.”

But it was the mandated target, as set by the Water Quality Control Board, and our sanitation districts were legally required to hit it.

Complicating matters, our chloride discharges were on the rise, thanks to the increased use of self-regenerating (salt-discharging) water softeners in our valley.

In 2003, the sanitation districts outlawed the installation of new salt-discharging softeners, and the voters later authorized the removal of existing ones — but that wouldn’t bring us down to 100 mg/l.

We needed to get the Regional Water Quality Board to raise the limit, which was faulty anyway.
We could live with the old standard of 190 mg/l.

In 2004, the downstream (Ventura County) agencies and the upstream (Santa Clarita Valley) agencies got together and agreed to conduct new scientific studies to “evaluate the appropriate chloride threshold for the protection of sensitive agriculture.”

Now we’d know for sure which was right — 100 mg/l or 190 mg/l or another number.

The joint agencies presented their findings to the Regional Water Quality Control Board, which revised the chloride limit to 117 mg/l.

Sadly, one thing was missing from the multi-agency studies of an “appropriate chloride threshold for the protection of sensitive agriculture”: a study of chloride impacts on crops in the Santa Clara River Valley.

You see, they did it again.

Instead of conducting an actual scientific study of downstream crops, the agencies hired the environmental engineering firm CH2M HILL to perform a peer review of the literature.

No new studies. Just the same-old, same-old rereading of the literature that didn’t necessarily apply directly to conditions in the Santa Clara River Valley.

And what did the literature say?

CH2M HILL filed its report in 2005. It read all of the studies of chloride uptake in avocados, strawberries and flowers from the 1950s to the mid-1990s — studies conducted everywhere from controlled greenhouse environments to places as far away as Israel.

For strawberries, CH2M HILL reported that the results “vary widely” and “did not provide sufficient data to determine an appropriate chloride threshold for irrigation water.”

For nursery crops — flowers — CH2M Hill said the most relevant study “showed evidence of adverse effects with sprinkler irrigation at 300 mg/l chloride.”

Let’s see. Strawberries: We don’t know. Flowers: 300 mg/l. The culprit must be the avocados.

Here is what CH2M HILL said about avocados:

“First, it must be noted that the literature provided no absolute thresholds, with supporting scientific evidence, that indicate a maximum concentration of chloride at which avocado trees will not grow or produce.”

CH2M HILL said some of the studies-done-elsewhere showed avocado leaf burn and flower damage starting at 120 mg/l. Some showed damage starting at 178 mg/l. The rest fell somewhere in the middle.

Avocados grown in greenhouse conditions — controlling for chloride — could withstand levels closer to 178 mg/l.

Avocados grown in nasty environments, with plenty of other factors to stunt growth, started suffering closer to 120 ppm.

To be on the safe side, CH2M HILL recommended a threshold of 100 mg/l to 120 mg/l, even though “there is clearly not enough evidence to propose an absolute threshold with the literature presently available.”

In 2007, another firm re-reviewed CH2M HILL’s review. It noted: “There is no literature stating that chloride or salt stress during flowering affects or does not affect (the) fruit.”

The 2007 study cited chloride levels at Camulos Ranch, 10 miles down Highway 126, where the chloride problem is considered most severe.

From June 2000 to December 2006 — when we still had many salt-discharging softeners in the Santa Clarita Valley — the rolling three-month average chloride level topped 150 mg/l just twice (150.67 and 153).

In the two hottest months of a drought year, we didn’t come close to 178 mg/l.

The average for all 79 months was 125.67 mg/l.

It makes you wonder. What is this really about?

The 2007 study noted that avocados in the Santa Clara River Valley face a plethora of dangers. Too cold, they freeze. Too hot, they burn. Too wet, they develop root rot. Too dry, the chloride level spikes. Too windy, they shrivel up.

After all, avocados are tropical fruit. They come from Mexico and Central and South America. Ventura farmers use sensitive Mexican rootstock. Guatemalan and West Indian rootstocks “are well known to be more salt tolerant than Mexican rootstocks,” CH2M HILL reported.

In the late 1880s, the favored crop in the Camulos Ranch area was grapes. Grapes are particularly chloride-resilient.

At the turn of the last century, citrus became the big cash crop. Oranges, lemons and limes are only slightly more delicate than grapes.

They can withstand about as much chloride as humans can handle in their drinking water (250 mg/l).

Only in the last decade has strawberry and avocado production eclipsed that of citrus.

What happens when the Ventura County farmers want to grow something even more delicate — something that can’t tolerate more than, say, 50 mg/l of chloride?

Will we have to subsidize their farms by paying to reduce the chloride level even further?

Under state law, the answer appears to be “yes.” We can’t impede a “beneficial use” of the river.

Where to go from here?

One: We need state law to redefine “beneficial use.” At the risk of telling downstream farmers what to grow, we “upstreamers” shouldn’t have to pay if they try to grow something that isn’t supposed to grow here.

Two: We know of no other sanitation district in California that is being held to such a low tolerance for chloride.

We need to fix a system in which political appointees who aren’t accountable to the voters can set water quality thresholds based on nothing more than a “feeling” — feelings that can cost communities hundreds of millions of dollars.

Three: We need our SCV Sanitation District board to say “no” to raising sewer fees and building new treatment facilities when it meets July 27.

We SCV residents shouldn’t be expected to pay to suck more salt out of the Santa Clara River if there is no scientific basis for doing so.

We did our part when we got rid of the salt-discharging water softeners.

Show us the hard science that says exactly how much chloride an avocado, strawberry or nursery plant in the Santa Clara River Valley can tolerate, and we’ll think about further reducing our salt discharges.

Until then, forget it.

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