8 ms·

It's directly beside a river.

JshWright 7y ago
It's unlikely an urban fire department is set up for any significant amount of drafting (pulling water from surface sources), if it's something they can do at all. You're absolutely right though, if you want big water, that's the way to get it. It's just that "big water" doesn't even begin to approach the scale of the water that would be necessary to directly fight this fire.
- vonmoltke 7y ago
  I would expect the fire department of a large city with navigable waterways to have fireboats, though, which by their very nature draft water. Even if the boat's own nozzles don't reach. they can generally be used as pumps for hoses on shore.
  - stcredzero 7y ago
    The devil is in the details. A "short" distance on a "small" island might well amount to a huge amount of hose. Then there's the logistics of getting all of that in place and hooked up. The trucks on site would need to pump to increase the pressure to usable levels, and all of that would have to be compatible. Getting enough trucks onsite might be a logistical challenge just in itself.
    - trickstra 7y ago
      like, really short: https://www.google.com/maps/place/Notre+Dame,+Paris,+France/@48.8525779,2.3488674,16.59z/data=!4m5!3m4!1s0x47e671e39dd448af:0xe95d8ec82cfaf643!8m2!3d48.8527288!4d2.3505635 https://www.google.com/maps/place/Notre+Dame,+Paris,+France/...
      - stcredzero 7y ago
        like, really short: The real world is complex. It's not all like software or taking multiple choice exams. Again the devil is in the details. Pay really close attention to the map legend. It looks like there's nearly 200 feet of distance from the closest water shown on that map and the nearest side of the cathedral. I really doubt that all fire trucks carry 200 feet of hard suction hose, or have pumps designed to draft through 200 feet of hard hose. "The NFPA 1901, Standard for Automotive Fire Apparatus – Requires pumpers to carry: 15 feet of large soft sleeve hose or 20 feet of hard suction hose" http://tkolb.net/tra_sch/FireHose/HoseBasics.html http://tkolb.net/tra_sch/FireHose/HoseBasics.html
        JshWright 7y ago
        Also, even if you had a pump by the river, hand-jacking that length of LDH requires a huge amount of physical effort, and would tie up a lot of manpower during a critical phase of the operation.
        mindcrime 7y ago
        You would never try to draft through 200 feet of hard suction. In fact, I'm relatively sure it would be impossible, since no matter how well you tighten the connections, there's pretty much always going to be a minute amount of vacuum loss at each coupling. In practice, few fire departments ever draft though more than 20 feet (2 sections) of hard suction, and even then it can be a challenge getting the pump primed, depending on any elevation difference between the water surface and the engine location, etc. In real life, if you were going to draft in an environment like this, (leaving aside any reference to fire boats for a moment), you'd drive an engine to within 20' or so of the water, have it draft, and then relay water to the fire scene using (usually) 5" LDH. But sometimes even getting an engine to within 20' of the water can be a challenge, based on the geography and circumstances. If the body of water you're drafting from is (strongly) subject to tides, that adds another complicating factor as your water source is now moving around, which could require constant re-positioning of the apparatus. Lay people always see fires near large bodies of water and think "Why is water supply a problem, they're surrounded by water?!?" But it's often more complicated than that. Source: was a firefighter and firefighting instructor for about a decade in a former life.
        7y ago
  - JshWright 7y ago
    I wasn't able to find any hard sources, but I don't see any evidence that the Paris Fire Brigade has any boats with any significant pumping capacity. Most of their boats seem to be rescue/dive focused, with small master stream deck guns.
- stcredzero 7y ago
  It's unlikely an urban fire department is set up for any significant amount of drafting (pulling water from surface sources), if it's something they can do at all. My understanding, which is probably quite out of date, is that it's mostly harbor firefighting boats which had this ability. A coworker of mine points out that many of the San Francisco manholes are actually covers for cisterns of water, which exist primarily for fighting fires after an earthquake possibly takes out the water mains and starts many fires. I should hope that San Francisco fire trucks can draft water to use these.
  - i_am_proteus 7y ago
    Former (volunteer) firefighter here: Park the truck next to the cistern. Connect a length of hose to the pump supply, drop the hose into the cistern. The pump will move water until it loses suction pressure.
    - JshWright 7y ago
      Not just any hose though, you need rigid walled hose. Regular fire hose would just collapse flat under suction. https://en.wikipedia.org/wiki/Hard_suction_hose https://en.wikipedia.org/wiki/Hard_suction_hose
    - stcredzero 7y ago
      Is the hose to be dropped into the cistern different from the other hoses? I would expect it to be reinforced, such that it wouldn't collapse from air pressure. Hoses downstream from a high pressure pump wouldn't need such reinforcement. However, it's different upstream from such pumps.
  - evasote 7y ago
    You can recognize the cisterns because there are big (like 20 ft in diameter) brick circles inlaid into the street in SF to mark the cisterns. Neat once you know what to look for
- chrisseaton 7y ago
  > It's unlikely an urban fire department is set up for any significant amount of drafting (pulling water from surface sources), if it's something they can do at all. London Fire Brigade for example has nine special pumps that can draw 2000 gallons a minute each from river or lake supplies. So that's 18,000 gallons a minute just from them. And that's a smaller fire brigade than Paris.
  - JshWright 7y ago
    Yeah, but that's not "a significant amount". It's certainly less than half of what you would need to fight this fire head on. That's also assuming all those engines are in-service, staffed, and can get there and get set up within a reasonable amount of time.
    - anigbrowl 7y ago
      You were wrong, give it up already.
- Animats 7y ago
  It's unlikely an urban fire department is set up for any significant amount of drafting (pulling water from surface sources), if it's something they can do at all. SFFD trucks have that capability, and it was used in the 1989 earthquake. It's intended for pulling water from the underground cisterns marked by a big ring of bricks in SF intersections. Terrible for the equipment to run salt water, but they had to.
  - lucb1e 7y ago
    I thought SFFD was some brand used by the French, but of course it's just USA-centric naming. (Took me forever to understand BART and I still have to look up name-based time zones like MST, which, no, thanks Wikipedia, is not Malaysia Standard Time at +8 but Mountain time at -7.) For anyone else confused: this earthquake was in San Francisco and this is about their Fire Department. It doesn't mean that French fire trucks have that capability 30 years later.
- deleted 7y ago
  [deleted]
- etrevino 7y ago
  The BBC said they were pulling water directly from the river, fyi.
  - JshWright 7y ago
    Yeah, I've seen at least two draft lines running. But at best that's going to be 3-4k GPM. Enough for a couple of those big water streams. You'd need >10x that to fight a fire like this head on (which they clearly didn't have, since they immediately went to salvage and exposure protection measures)
bobwaycott 7y ago
The Seine is not directly beside Notre Dame. It’s a steep drop and 200-300ft away depending on angles. A standard fire hose is 50ft. A supply/relay hose is typically 100ft. They can’t just hook up a few hoses, dunk them in the Seine, and then instantly put the fire out. There were notable logistical issues to get enough firefighters on-site given it’s an island, and there were a ton of people around when the fire broke out. They wound up having 400 firefighters on-site until midnight to get it under control and save the structure. I’m pretty confident they did all they could, and HN’s armchair firefighters aren’t likely to have done any better.

It's unlikely an urban fire department is set up for any significant amount of drafting (pulling water from surface sources), if it's something they can do at all. You're absolutely right though, if you want big water, that's the way to get it. It's just that "big water" doesn't even begin to approach the scale of the water that would be necessary to directly fight this fire.

vonmoltke 7y ago
I would expect the fire department of a large city with navigable waterways to have fireboats, though, which by their very nature draft water. Even if the boat's own nozzles don't reach. they can generally be used as pumps for hoses on shore.
- stcredzero 7y ago
  The devil is in the details. A "short" distance on a "small" island might well amount to a huge amount of hose. Then there's the logistics of getting all of that in place and hooked up. The trucks on site would need to pump to increase the pressure to usable levels, and all of that would have to be compatible. Getting enough trucks onsite might be a logistical challenge just in itself.
  - trickstra 7y ago
    like, really short: https://www.google.com/maps/place/Notre+Dame,+Paris,+France/@48.8525779,2.3488674,16.59z/data=!4m5!3m4!1s0x47e671e39dd448af:0xe95d8ec82cfaf643!8m2!3d48.8527288!4d2.3505635 https://www.google.com/maps/place/Notre+Dame,+Paris,+France/...
    - stcredzero 7y ago
      like, really short: The real world is complex. It's not all like software or taking multiple choice exams. Again the devil is in the details. Pay really close attention to the map legend. It looks like there's nearly 200 feet of distance from the closest water shown on that map and the nearest side of the cathedral. I really doubt that all fire trucks carry 200 feet of hard suction hose, or have pumps designed to draft through 200 feet of hard hose. "The NFPA 1901, Standard for Automotive Fire Apparatus – Requires pumpers to carry: 15 feet of large soft sleeve hose or 20 feet of hard suction hose" http://tkolb.net/tra_sch/FireHose/HoseBasics.html http://tkolb.net/tra_sch/FireHose/HoseBasics.html
      - JshWright 7y ago
        Also, even if you had a pump by the river, hand-jacking that length of LDH requires a huge amount of physical effort, and would tie up a lot of manpower during a critical phase of the operation.
      - mindcrime 7y ago
        You would never try to draft through 200 feet of hard suction. In fact, I'm relatively sure it would be impossible, since no matter how well you tighten the connections, there's pretty much always going to be a minute amount of vacuum loss at each coupling. In practice, few fire departments ever draft though more than 20 feet (2 sections) of hard suction, and even then it can be a challenge getting the pump primed, depending on any elevation difference between the water surface and the engine location, etc. In real life, if you were going to draft in an environment like this, (leaving aside any reference to fire boats for a moment), you'd drive an engine to within 20' or so of the water, have it draft, and then relay water to the fire scene using (usually) 5" LDH. But sometimes even getting an engine to within 20' of the water can be a challenge, based on the geography and circumstances. If the body of water you're drafting from is (strongly) subject to tides, that adds another complicating factor as your water source is now moving around, which could require constant re-positioning of the apparatus. Lay people always see fires near large bodies of water and think "Why is water supply a problem, they're surrounded by water?!?" But it's often more complicated than that. Source: was a firefighter and firefighting instructor for about a decade in a former life.
      - 7y ago
- JshWright 7y ago
  I wasn't able to find any hard sources, but I don't see any evidence that the Paris Fire Brigade has any boats with any significant pumping capacity. Most of their boats seem to be rescue/dive focused, with small master stream deck guns.
stcredzero 7y ago
It's unlikely an urban fire department is set up for any significant amount of drafting (pulling water from surface sources), if it's something they can do at all. My understanding, which is probably quite out of date, is that it's mostly harbor firefighting boats which had this ability. A coworker of mine points out that many of the San Francisco manholes are actually covers for cisterns of water, which exist primarily for fighting fires after an earthquake possibly takes out the water mains and starts many fires. I should hope that San Francisco fire trucks can draft water to use these.
- i_am_proteus 7y ago
  Former (volunteer) firefighter here: Park the truck next to the cistern. Connect a length of hose to the pump supply, drop the hose into the cistern. The pump will move water until it loses suction pressure.
  - JshWright 7y ago
    Not just any hose though, you need rigid walled hose. Regular fire hose would just collapse flat under suction. https://en.wikipedia.org/wiki/Hard_suction_hose https://en.wikipedia.org/wiki/Hard_suction_hose
  - stcredzero 7y ago
    Is the hose to be dropped into the cistern different from the other hoses? I would expect it to be reinforced, such that it wouldn't collapse from air pressure. Hoses downstream from a high pressure pump wouldn't need such reinforcement. However, it's different upstream from such pumps.
- evasote 7y ago
  You can recognize the cisterns because there are big (like 20 ft in diameter) brick circles inlaid into the street in SF to mark the cisterns. Neat once you know what to look for
chrisseaton 7y ago
> It's unlikely an urban fire department is set up for any significant amount of drafting (pulling water from surface sources), if it's something they can do at all. London Fire Brigade for example has nine special pumps that can draw 2000 gallons a minute each from river or lake supplies. So that's 18,000 gallons a minute just from them. And that's a smaller fire brigade than Paris.
- JshWright 7y ago
  Yeah, but that's not "a significant amount". It's certainly less than half of what you would need to fight this fire head on. That's also assuming all those engines are in-service, staffed, and can get there and get set up within a reasonable amount of time.
  - anigbrowl 7y ago
    You were wrong, give it up already.
Animats 7y ago
It's unlikely an urban fire department is set up for any significant amount of drafting (pulling water from surface sources), if it's something they can do at all. SFFD trucks have that capability, and it was used in the 1989 earthquake. It's intended for pulling water from the underground cisterns marked by a big ring of bricks in SF intersections. Terrible for the equipment to run salt water, but they had to.
- lucb1e 7y ago
  I thought SFFD was some brand used by the French, but of course it's just USA-centric naming. (Took me forever to understand BART and I still have to look up name-based time zones like MST, which, no, thanks Wikipedia, is not Malaysia Standard Time at +8 but Mountain time at -7.) For anyone else confused: this earthquake was in San Francisco and this is about their Fire Department. It doesn't mean that French fire trucks have that capability 30 years later.
deleted 7y ago
[deleted]
etrevino 7y ago
The BBC said they were pulling water directly from the river, fyi.
- JshWright 7y ago
  Yeah, I've seen at least two draft lines running. But at best that's going to be 3-4k GPM. Enough for a couple of those big water streams. You'd need >10x that to fight a fire like this head on (which they clearly didn't have, since they immediately went to salvage and exposure protection measures)

bobwaycott 7y ago

The Seine is not directly beside Notre Dame. It’s a steep drop and 200-300ft away depending on angles. A standard fire hose is 50ft. A supply/relay hose is typically 100ft. They can’t just hook up a few hoses, dunk them in the Seine, and then instantly put the fire out. There were notable logistical issues to get enough firefighters on-site given it’s an island, and there were a ton of people around when the fire broke out. They wound up having 400 firefighters on-site until midnight to get it under control and save the structure. I’m pretty confident they did all they could, and HN’s armchair firefighters aren’t likely to have done any better.