Flood watches issued for L.A. burn areas as storm moves in

Los Angeles Times ^ | October 13, 2009 | Baxter Holmes and Robert J. Lopez

[americanophile]

The National Weather Service has issued flash-flood watches this morning for mountain burn areas from Santa Barbara to San Bernardino as a powerful winter storm moved into Southern California.

Rain was beginning to fall this morning, with the strongest portions of the storm expected late today and early Wednesday morning. The National Weather Service issued the flood watches for areas burned by the fires in Santa Barbara as well as the massive Station fire is Los Angeles County and the Sheep fire near Wrightwood.

The watch also includes areas burned in last year's large Sayre and Marek fires in the San Fernando Valley areas.

"Flash-flooding and debris flows will be a particular threat in and below the recent burn areas," the NWS said in its statement.

Officials said residents in burn areas should prepare for possible mudslides, rock slides and debris flows "even during periods with little or no rain falling."

The storm is expected to dump 3 to 6 inches of rain.

As news of the coming wet weather circulated, residents in charred foothill areas scrambled to fill sandbags or pack their belongings and flee areas prone to flooding. Officials also worked to place huge concrete mudslide barriers along roads in areas including La Cañada Flintridge.

[americanophile]

Personally, I can't believe it's actually raining...it hasn't rained here since April that I can recall...APRIL! Everything needs a bath. Still, this 'storm' is what the rest of the country would call simple 'rain.'

[alloysteel]

And, once again, the questionable wisdom of building a house on a terrace bulldozed out of a hilside will be exposed, as the downhill side of the lawn and a portion of the house will slide down the grade....

Will Californians NEVER learn - that the state is largely in a seasonal fire zone, and that when the vegetation is gone, everything churns up into mud when even a modest rain comes along?

And it can be some of the worst cursed mud in the world, slick and seemingly bottomless, affording almost no traction to the driven wheel. Only way out is attaching a winch to a solid structure that may be a quarter of a mile away.

Or wait for the mud to dry up.

[rahbert]

Vietnam has some pretty tenacious mud, based on seeing
M-48s and Cat D-8s’ getting stuck in it.

In WA we would call it a drizzle.

[americanophile]

...half the world builds on hillsides...it shouldn’t be difficult.

[Sporaticus]

Its raining here in the OC. ~Rare.
Most winters hardly any rain, luckier wet winters
it just rains mostly at night. This sucks.

[SZonian]

Well, I suppose with you living in a state whose highest point is about 300’ in elevation it would be difficult to argue with you. However, most of the homes that may be affected were built decades ago, although there has been alot of newer construction in the past few years. Many are building in the high desert areas now, but that only causes water “shortages”*

SZ

* man made shortages due to a non-native minnow that deserves more rights than farmers and taxpayers.

[alloysteel]

Didn’t ALWAYS live in Florida - I used to live in Carson City, Nevada. We got five inches of rainfall there - a year. Had to go UPHILL to get to Lake Tahoe, but then, almost everybody has to do that. There was a special clause in homeowners’ insurance to cover earthquake damage, and the first vegetation to spring up after a brush fire was cheat grass, which made the fuel for the NEXT brush fire, caused by dry-strike lightning.

Problems in Florida are a bit different. When the aquifer gets pumped dry, there are huge sinkholes that form, swallowing houses and streets. As the aquifers go down, the underlying marl, mostly calcium carbonate, collapses. And the marshes dry up, again a fire hazard, as the ground is mostly decomposed organic matter, and once a fire starts, it burns under the surface, as happened to the dried portions of Lake Okeechobee (which is only about two or three feet deep even when full).

Florida goes into drought status when we miss two consecutive weeks of rain. Most of the non-organic soil consists of either a clay that is totally unable to absorb water, or of sand that lets the water sink away within minutes of a rain. There is no middle ground.

[SZonian]

You’re correct, there really is “No middle ground.” Every state has it’s issues, some natural, some man made. I do agree with the premise that it’s foolhardy to build in areas that are prone to problems and I resent having to subsidize the rebuilding of homes destroyed in areas that have those problems.

SZ