Water? I hardly know her! (Part I: The Science of Discolored Water)
by The Editor and Sam Joaquin
If you're like us, this whole NE Fresno water "crisis" probably seems a bit confusing. You've got politicians squabbling, scientists sciencing, reporters misreporting, and people complaining of lead poisoning. We've decided to cut through all the noise and break down what's happening, who the major players are, and how Fresno has found itself in this situation.
Part I: The Science of Discolored Water
All of this begins with groundwater. What is groundwater? Essentially, it's water that's below the surface. This is the same water that people tap into if they have a well.
Despite its name, groundwater is not found on the ground---that's surface water. Lakes, rivers, oceans, ponds, sloughs, etc. If it's on the ground, it's surface water. All of these sources are useful for drinking and irrigation except for the ocean because it's full of salt.
In normal circumstances, groundwater is constantly being replenished by surface water which seeps down to something called an "aquifier" which is a fancy word for where groundwater is stored. However, we all know that the San Joaquin Valley (SJV) is anything but normal. Farmers have long been using groundwater because there simply isn't enough surface water to go around, and, once again, normally this wouldn't be so bad, but in the SJV the groundwater is part of what is supporting the valley floor. The water is stored in the porous spaces between grains of sand; when you take it out, the sand compacts and the space is gone. Like Fulton 55's "no in's and out's" policy, once it's out there's no going back, even if you were dancing with a pretty girl and forgot to get her number.
As the water is taken out, the valley floor loses elevation. Here's a famous picture from 1977:
The years on the poll mark where the valley floor's elevation was at those times. Since 1977, the valley floor has sunk another 17 feet.
California produces about 12.8% of our nation's food (based on revenue) and most of that comes from the SJV, but 75% of California's rainfall occurs north of Sacramento. In laymen's terms, this means we need a whole lot of water but have very little of it. We're running out of groundwater and the drought isn't helping.
So, what does all this have to do with funny colored water in NE Fresno?
The water in NE Fresno has traditionally been groundwater which is chemically inert (it's been sitting in the ground and bonded with anything it could possibly bond to.) As you can see, solely using groundwater is totally unsustainable, so the city began treating water from the Enterprise Canal and introducing it to the water supply.
So, where once water would flow cleanly through pipes and not bond with anything, suddenly you've got water that wants to bond with things, particularly galvanized pipes, which a lot of homes in NE Fresno have.
This might seem confusing because we found an article that said the chemistry changes when ground and surface waters are mixed together. That's wrong. It's all the surface water's fault.
What about the complaints of lead?
Lead is the big fear right now because of what recently happened in Flint, MI, so real quick, here's how Flint and Fresno are similar and how they're not:
In April of 2014, Flint started using water from the Flint River instead of from the Detroit Water and Sewage Department. The water in the Flint River was more corrosive (kind of like the water from the Enterprise Canal) and caused lead pipes to leech into the water. This caused about 5% of the children in Flint to test positive for high amounts of lead in their systems.
Fresno, however, doesn't have lead pipes. While it's true that 94 faucets in 64 homes have tested positive for lead, of the 376 homes tested for lead, only 4 kitchen faucets tested higher than the EPA threshold of 15 parts per billion (there's a reason they tell you not to drink water from your hose). For those keeping track, that's about 1.06% of homes.
The Bee estimates there are 15,000 homes in NE Fresno, so by our calculation that means there are probably 159 homes in Fresno that would test above the EPA threshold.
Is this something to take seriously? Yes. Of course.
Is Fresno another Flint? Absolutely not.
To quote the Fresno Bee:
So there you go, that's the science of it. Next time, we'll explain the history, the lies, and the cover-up that lead (no pun intended) us to this.
If you're like us, this whole NE Fresno water "crisis" probably seems a bit confusing. You've got politicians squabbling, scientists sciencing, reporters misreporting, and people complaining of lead poisoning. We've decided to cut through all the noise and break down what's happening, who the major players are, and how Fresno has found itself in this situation.
Part I: The Science of Discolored Water
All of this begins with groundwater. What is groundwater? Essentially, it's water that's below the surface. This is the same water that people tap into if they have a well.
Despite its name, groundwater is not found on the ground---that's surface water. Lakes, rivers, oceans, ponds, sloughs, etc. If it's on the ground, it's surface water. All of these sources are useful for drinking and irrigation except for the ocean because it's full of salt.
In normal circumstances, groundwater is constantly being replenished by surface water which seeps down to something called an "aquifier" which is a fancy word for where groundwater is stored. However, we all know that the San Joaquin Valley (SJV) is anything but normal. Farmers have long been using groundwater because there simply isn't enough surface water to go around, and, once again, normally this wouldn't be so bad, but in the SJV the groundwater is part of what is supporting the valley floor. The water is stored in the porous spaces between grains of sand; when you take it out, the sand compacts and the space is gone. Like Fulton 55's "no in's and out's" policy, once it's out there's no going back, even if you were dancing with a pretty girl and forgot to get her number.
As the water is taken out, the valley floor loses elevation. Here's a famous picture from 1977:
The years on the poll mark where the valley floor's elevation was at those times. Since 1977, the valley floor has sunk another 17 feet.
California produces about 12.8% of our nation's food (based on revenue) and most of that comes from the SJV, but 75% of California's rainfall occurs north of Sacramento. In laymen's terms, this means we need a whole lot of water but have very little of it. We're running out of groundwater and the drought isn't helping.
So, what does all this have to do with funny colored water in NE Fresno?
The water in NE Fresno has traditionally been groundwater which is chemically inert (it's been sitting in the ground and bonded with anything it could possibly bond to.) As you can see, solely using groundwater is totally unsustainable, so the city began treating water from the Enterprise Canal and introducing it to the water supply.
So, where once water would flow cleanly through pipes and not bond with anything, suddenly you've got water that wants to bond with things, particularly galvanized pipes, which a lot of homes in NE Fresno have.
This might seem confusing because we found an article that said the chemistry changes when ground and surface waters are mixed together. That's wrong. It's all the surface water's fault.
What about the complaints of lead?
Lead is the big fear right now because of what recently happened in Flint, MI, so real quick, here's how Flint and Fresno are similar and how they're not:
In April of 2014, Flint started using water from the Flint River instead of from the Detroit Water and Sewage Department. The water in the Flint River was more corrosive (kind of like the water from the Enterprise Canal) and caused lead pipes to leech into the water. This caused about 5% of the children in Flint to test positive for high amounts of lead in their systems.
Fresno, however, doesn't have lead pipes. While it's true that 94 faucets in 64 homes have tested positive for lead, of the 376 homes tested for lead, only 4 kitchen faucets tested higher than the EPA threshold of 15 parts per billion (there's a reason they tell you not to drink water from your hose). For those keeping track, that's about 1.06% of homes.
The Bee estimates there are 15,000 homes in NE Fresno, so by our calculation that means there are probably 159 homes in Fresno that would test above the EPA threshold.
Is this something to take seriously? Yes. Of course.
Is Fresno another Flint? Absolutely not.
To quote the Fresno Bee:
The key difference between Flint’s well-publicized troubles and what is happening in Fresno is the widespread use of lead pipes in Flint, “and there’s no evidence there’s any lead pipes in Fresno,” [Marc Edwards, a professor of civil and environmental engineering at Virginia Tech] said.
“The health threat from lead pipe in Flint vs. galvanized iron pipe is at least 100 times higher,” Edwards said. “Take the lead pipe out of the equation, and you don’t have nearly the same problem (in Fresno). It’s two orders of magnitude lower to start with.”
He added that while Fresno has been treating its water to prevent lead and copper corrosion, “Flint obviously had no corrosion control program at all.”
[source]If you want to go a little further, here's a complete history of Flint's water crisis.
So there you go, that's the science of it. Next time, we'll explain the history, the lies, and the cover-up that lead (no pun intended) us to this.
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