Water Pressure - Universal Studios fire?

[1OLDTIMER]

http://http://cms.firehouse.com/web/online/News/Water-Pressure-Blamed-for-Universal-Studios-Damage/46$59693

At one point, Sunday's fire was two city blocks wide, and low water pressure forced firefighters to get reserves from lakes and ponds on the 400-acre property. The blaze was contained to the back lot, but burned for more than 12 hours before the final flames were extinguished.

"The water pressure situation was a challenge," Los Angeles County Fire Chief Michael Freeman said. "This fire moved extremely fast."

I don't mean to be a S/A, and I may be missing something here, but LOW water PRESSURE? Isn't that what PUMPING ENGINES are used for...to INCREASE prssure? Water SUPPLY was not mentioned...only pressure.

[txgp17]

More details will have to come out before we pounce on this issue. I would assume that someone misspoke about the water volume, and somehow that got transformed into "low pressure" before it went to print.

Low water pressure doesn't mean anything if you maximize the water connections and put a pumper at the hydrant, assuming the hydrant has a 4½" steamer.

[chiefengineer11]

http://http://cms.firehouse.com/web/...amage/46$59693


I don't mean to be a S/A, and I may be missing something here, but LOW water PRESSURE? Isn't that what PUMPING ENGINES are used for...to INCREASE prssure? Water SUPPLY was not mentioned...only pressure.

What do they use for supply lines? Hopefully, LDH of some sort.

Back in the day, we always blamed low water pressure for our instant parking lots. The reality is that we were using 2-1/2" and single 3" lines for water supply. The water was there, we just didn't have the means and the knowledge to move it from where it was to where it was needed. By knowledge, I mean a chief who said that friction loss was 10 lbs./100', period.

Stay safe out there, everyone goes home!

[Eng3ineer]

What do they use for supply lines? Hopefully, LDH of some sort.

Back in the day, we always blamed low water pressure for our instant parking lots. The reality is that we were using 2-1/2" and single 3" lines for water supply. The water was there, we just didn't have the means and the knowledge to move it from where it was to where it was needed. By knowledge, I mean a chief who said that friction loss was 10 lbs./100', period.

Stay safe out there, everyone goes home!

It was on news today that they were flowing 18,000 plus GPM at the height of fire, sounds like to me they may have just over taxed that entire water grid... Hell i'd be happy if I had 18,000 gpm at hand...

On hose size from what i've read in the past they use 4" LDH for supply...

Jason

[chiefengineer11]

It was on news today that they were flowing 18,000 plus GPM at the height of fire, sounds like to me they may have just over taxed that entire water grid... Hell i'd be happy if I had 18,000 gpm at hand...

On hose size from what i've read in the past they use 4" LDH for supply...

Jason

Your assessment seems quite reasonable. Thanks for the info. Even though I personnally prefer 5", enough 4" lines with adequate relay engines should do the trick. For that amount of water, the same thing should be said for 5".

[1OLDTIMER]

It was on news today that they were flowing 18,000 plus GPM at the height of fire, sounds like to me they may have just over taxed that entire water grid... Hell i'd be happy if I had 18,000 gpm at hand...

The fact is that I don't understand all that I know about anything anymore... however...it appears that there are a number of small lakes and ponds ON the property, with their OWN paid fire protection. I would think if the water grid is/was a problem, that pre-planning would have included DRAFTING from any of the ponds...providing an unlimited supply?

[Chief1FF]

The fact is that I don't understand all that I know about anything anymore... however...it appears that there are a number of small lakes and ponds ON the property, with their OWN paid fire protection. I would think if the water grid is/was a problem, that pre-planning would have included DRAFTING from any of the ponds...providing an unlimited supply?

Most big (Not ALL) metropolitian fire departments I have found do not have a clue when it comes to drafting. Because they are usually well Hydranted. In the tonwnship I live in we have two departments, the department I run with has 50% of the area with no hydrants. The run district of the other department is all hydrant. Guess who is not used for drafting operations!

Again most departments with areas that are all hydrants don't ever draft and therefore when they have too they are lost. I have seen departments in these areas, when they train drivers they don't even cover drafting operations because they believe with hydrants they will never have to draft!

[txgp17]

Most big (Not ALL) metropolitan fire departments I have found do not have a clue when it comes to drafting. Because they are usually well Hydranted.

Here Here!

My Dept of 21 Stations doesn't even equip the Engines properly to allow the drivers to draft. A lot of our Engines don't have a suction strainer at all, and they carry 4.5" suction tube that is choked down to a 4" Storz adapter so they can go through the Piston Intake Valve. This limits flow to no more than 750-800 GPM.

[1OLDTIMER]

My Dept of 21 Stations doesn't even equip the Engines properly to allow the drivers to draft. A lot of our Engines don't have a suction strainer at all, and they carry 4.5" suction tube that is choked down to a 4" Storz adapter so they can go through the Piston Intake Valve. This limits flow to no more than 750-800 GPM.

Again most departments with areas that are all hydrants don't ever draft and therefore when they have too they are lost. I have seen departments in these areas, when they train drivers they don't even cover drafting operations because they believe with hydrants they will never have to draft!

REALLY! To me, this is a VERY, VERY sad state of affairs...to the point of embarrassment. If I may ask [without appearing to have completely to have lost my mind], what is the reason(s) for not carrying hard suction, and [at least] train on drafting today...it is not rocket science?

I thought [my fault for thinking] that ALL REAL fire PUMPERS carried at min., 2 sections of hard suction. A pump should be able to pump from ANY scouce, not just from hydrants or "slop tanks." This then may help explain the LOW PRESSURE mentioned in the original story, or as we use to say...getting caught with your pants down in public.

Thanks for the information.

[Eng3ineer]

Here Here!

My Dept of 21 Stations doesn't even equip the Engines properly to allow the drivers to draft. A lot of our Engines don't have a suction strainer at all, and they carry 4.5" suction tube that is choked down to a 4" Storz adapter so they can go through the Piston Intake Valve. This limits flow to no more than 750-800 GPM.

Same here there not one section of any hose that you can draft with... Then again there not any static water source that we could reach if did carry any... Everything here within the city limits has hydrant's 3000+ of them...

On if we could draft there might be 10 guys at the most that could do it, but those 10 me included also belong to Vol. depts. were we have to draft for water supply... pond,dumptanks,etc...


Jason

[1OLDTIMER]

Same here there not one section of any hose that you can draft with... Then again there not any static water source that we could reach if did carry any... Everything here within the city limits has hydrant's 3000+ of them...

Jason,

Borrow a couple sections of H/S from your vol. dept., and conduct a mini-class on "drafting," just in case the supply from within the [3000+ hydrant] city mains would be interrupted during a fire. I think there are more static water sources than realized, i.e., a backyard pool, ditch, small creek, etc. This has happened more than we realize, from a contractor accidently damaging a main, or from just "plain ole" infrastructure failure/collapse. At least you would have a PLAN-B in the big city.

Whata ya think?

[Bones42]

Whata ya think?

I think a lot of people are going to be very upset if the local FD shows up and starts drafting from their backyard pools for no reason other than to practice an unlikely event.

There are plenty of places that don't have a need for drafting operations. There are plenty of places that don't have a need for hydrant operations.

[1OLDTIMER]

I think a lot of people are going to be very upset if the local FD shows up and starts drafting from their backyard pools for no reason other than to practice an unlikely event.

I don't think I suggested PRACTICING at/from someone's pool...just practice DRAFTING [for those who do not know how]...in case the supply from within the [3000+ hydrant] city mains would be interrupted during a fire...possibily THEN from someone's pool.

There are plenty of places that don't have a need for drafting operations. There are plenty of places that don't have a need for hydrant operations.

an unlikely event?

Yes...like at Universal Studios...my entire POINT in this thread. Water, water everywhere...but we can't hook-up to a hydrant or tanker...so we'll just blame insuffient water supply...instead of being able to DRAFT.

Help me understand...what is the problem with not knowing HOW and/or being ABLE to DRAFT if needed...one of the very first thing's the FD EVER did? I thought [obviously my fault] this would be automatic on learning how to run a pump.

[N2DFire]

http://http://cms.firehouse.com/web/online/News/Water-Pressure-Blamed-for-Universal-Studios-Damage/46$59693


I don't mean to be a S/A, and I may be missing something here, but LOW water PRESSURE? Isn't that what PUMPING ENGINES are used for...to INCREASE prssure? Water SUPPLY was not mentioned...only pressure.

I figured that someone would have answered this already but anyhow - here goes.

If you turn on the tap in any given sink served by a municipal water system (or a fire hydrant) what happens?
Water comes out (hopefully - if you get beer call me!!)

What makes it come out?
Pressure (from within-the municipal system)

Where does the pressure come from?
Pressure comes from 2 basic sources:
1) Pumps - typically located at the water source and/or treatment facilities. However larger systems may have pressure boosting pump stations in outlying areas (works the same as fire engines in a relay pumping situation).

2) Gravity - Ever wonder why most storage tanks are built above ground (or even elevated into the air)? It's to add pressure to the system from gravity. Also you get some pressure from elevation gain - that's why reservoirs are typically built at a higher altitude than the community they serve.

Given that someone said that they pumped as much as 18,000 plus GPM & the fact that the fire burned for more than 12 hours - that's a total of 12,960,000 gallons (18,000 GPM * 60 Min * 12 Hours).

Now if you factor in the following:
1) During the fire the regular load (drain) on the system didn't stop
2) The pumping capacity of the water system is not designed to keep pace with this type of demand (hence the use of gravity fed storage i.e. tanks)

Eventually the total fire flow is going to surpass what the system can supply and then the pressure in the water mains will fall & flow is therefore diminished.

Now for those that have forgotten (or were never taught) you can not simply hook your hard sleeve suction to a hydrant and attempt to "pull" water out of the system. Doing so could result in pulling a vacuum on the water mains (which they are not designed to withstand) and thus collapse them. This will not only make your water supply problem much worse, it also results in major repair cost to the city water system.

That's where "low water pressure" enters the equation, how it results in decreased water supply, and thus why it hampered firefighting efforts.


Also - I don't mean to be a S/A either but the article simply said that firefighters were forced to get water from lakes and ponds. Exactly where did it say anything about them having trouble in doing so or not knowing how to draft from a static source?? I don't understand why everyone seems to be up in arms over an inability to draft when as far as I can ascertain - there wasn't a problem other than an extremely large fire that I'm sure would have taxed the resources and capabilities of any fire department.

[txgp17]

REALLY! To me, this is a VERY, VERY sad state of affairs...to the point of embarrassment. If I may ask [without appearing to have completely to have lost my mind], what is the reason(s) for not carrying hard suction, and [at least] train on drafting today...it is not rocket science?

My Dept has a Class 1 ISO rating, and it was done completely with pressurized hydrants. As a result, people developed a "we don't need to draft" attitude, and from there, things only went downhill.

I thought [my fault for thinking] that ALL REAL fire PUMPERS carried at min., 2 sections of hard suction. A pump should be able to pump from ANY source, not just from hydrants or "slop tanks." This then may help explain the LOW PRESSURE mentioned in the original story, or as we use to say...getting caught with your pants down in public.

Thanks for the information.

The point is, my Dept can draft, just not well. We can't always make connections to dry hydrants with 6" threads, and we can't draft more than 750 GPM with our present equipment. Only two engines in our Dept have 6" suction hose, so those are the only ones that can exceed 1,000 GPM from a Draft.

[Bones42]

Yes...like at Universal Studios...my entire POINT in this thread. Water, water everywhere...but we can't hook-up to a hydrant or tanker...so we'll just blame insuffient water supply...instead of being able to DRAFT

they pumped as much as 18,000 plus GPM

but the article simply said that firefighters were forced to get water from lakes and ponds. Exactly where did it say anything about them having trouble in doing so or not knowing how to draft from a static source?? I don't understand why everyone seems to be up in arms over an inability to draft when as far as I can ascertain - there wasn't a problem other than an extremely large fire that I'm sure would have taxed the resources and capabilities of any fire department.

Please don't let FACTS get in the way of a good rant.

[Eng3ineer]

Jason,

Borrow a couple sections of H/S from your vol. dept., and conduct a mini-class on "drafting," just in case the supply from within the [3000+ hydrant] city mains would be interrupted during a fire. I think there are more static water sources than realized, i.e., a backyard pool, ditch, small creek, etc. This has happened more than we realize, from a contractor accidently damaging a main, or from just "plain ole" infrastructure failure/collapse. At least you would have a PLAN-B in the big city.

Whata ya think?

It could be done if needed and it has before in 2000 we had big ice storm hit here and knocked out all power for weeks... Guess what the water dept at the time didn't have back up power at the two treatment plants and pumping stations, so no water at all for few days and this was more than just our city it effected 9 or 10 other city's as well since our city supplys there water also... We had few fire during that time, but luck on our side the low area's still had some pressure from all the above ground storage tanks... We have some where around 10 above ground tank with the biggest being 1 millon gallons and the smallest being 500,000 gals...

Now for drafting from pond/lakes/creeks/pools in the city it could be done but a floating pump or something like the turbo draft would be needed due to distance from the road to water's edge... I can think one maybe two ponds that we might be able to reach with hard suction...

Jason

[chiefengineer11]

Jason - Quite off the subject, but what's the structure there? Are Texarkana, Ark. and Texarkana, Tex. different departments, or do you function as one?

[neiowa]

Now for those that have forgotten (or were never taught) you can not simply hook your hard sleeve suction to a hydrant and attempt to "pull" water out of the system. Doing so could result in pulling a vacuum on the water mains (which they are not designed to withstand) and thus collapse them. This will not only make your water supply problem much worse, it also results in major repair cost to the city water system.

Who said anything about hooking hard suction to a hydrant?

Actually you can pull a significant vacumn in a PCV main (properly installed) without damaging the main. There is some difference of opinion regarding potential damage to system from water hammer as a result of hydrant hookup (see USDA rural water systems vs the rest of/the real world).

[Eng3ineer]

Jason - Quite off the subject, but what's the structure there? Are Texarkana, Ark. and Texarkana, Tex. different departments, or do you function as one?

I'll PM or e-mail...

Jason