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There was mention of springs drying up after wildfires.
If so, why?

I'm not a hydrologist, but the main thing that comes to mind loss of vegetation and erosion allows water to run off faster and buffers less of it, thereby reducing the replenishment of aquifers that feed the springs. There's probably more to it than that. I wish I kept track of such things, but I remember a couple once-reliable springs in the Catalinas that dried up or became much less reliable after fire.

It depends. Where did you read this?

In the Gila, they started to allow fires to burn, as they should have, because springs were flowing less and drying up. Trees were sucking up all the water before it got into the rock to later emerge from the springs.

If the springs water is old enough, then there would be no affect.

But, if soils become hydrophobic, springs or streams silt up, and the soil that once helped recharge a spring is now washed into the spring, then what Load says is true.

My understanding of it is similar to big_load in that the faster runoff prevents replenishment but also that a flash flood event as is typical here can actually alter how water reaches the aquifer in an area.

Jim_H wrote:Where did you read this?

Thought I read it on HAZ but only found light references looking back.
At any rate... =)
I tried several google searches of the subject with no substantial supporting results.

big_load wrote:the main thing that comes to mind loss of vegetation and erosion allows water to run off faster and buffers less of it, thereby reducing the replenishment of aquifers that feed the springs.

Seems feasible for an intermittent seep or a spring that is known to struggle.
Reavis Creek @ Fireline might dry up. Albeit typically dependable it was slightly finicky.

Had not considered flash flooding, good point.

Doubting Horton or Thunder River dry up unless there is a shift in tectonic plates.

@joebartels
It is a commonly supported idea, I think. I was just wondering if there was a specific area being talked about.

Maybe @arizona_water is still lurking? I think he might be able to provide educated, factual data specific to Arizona.

(I can't add anything of substance but the replies above seem logical to me).

@chumley
Thanks, chumley! Still lurking ;) You all hit the key points, I think. I reached out to a couple hydrologists and I'll get back to you with their professional answers. But I think the short answer is:
Yes, surface water runoff is more immediate after a fire removes vegetation. But in general, springs are more affected by human activities than by natural ones. If you ever hear of a spring going dry after a fire, it's more likely the compounding impacts of well pumping. Most perennial springs in AZ are a product of shallow aquifers. Yes, aquifers are impacted by increased runoff. But in (most of) Arizona, that runoff has a marginal impact on aquifer recharge compared to groundwater pumping.
And while I'm on that subject, most recharge in central AZ is artificial, i.e. done by humans.

@arizona_water So what you’re saying is if the fire destroyed the Pinto mine, then then the springs would be better than ever!?

@chumley

I hiked to Hopi Spring just a year after the Willow Fire in the Mazatzals. The area was nearly moonscape but the spring still flowing in late June but the water was undrinkable. Casterson Seep seemed unaffected by the fire.