Firefighters are enjoying the quiet of a summer afternoon in their fire station discussing the night’s dinner when the stationhouse speakers crackle. The dispatcher announces “a reported structure fire” with a sense of urgency. Within seconds, firefighters are hustling toward their...
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If you know your community, then you should know where the good water supplies and the bad water supplies are located.
The forward stretch is used to quickly establish a water supply and can help firefighters start a fire attack and keep it going without interruption of water.
Firefighters are enjoying the quiet of a summer afternoon in their fire station discussing the night’s dinner when the stationhouse speakers crackle. The dispatcher announces “a reported structure fire” with a sense of urgency.
Within seconds, firefighters are hustling toward their apparatus. The alarm is repeated twice. A few more seconds and fire companies are rolling. Firefighters are aware of the neighborhood from the address given. Enroute, firefighters are talking in the cab while donning their gear and equipment. As the first-due engine turns the last street corner before arriving at the reported address, it becomes obvious – a well-involved, two-story, wood-frame mixed occupancy about halfway down the block is sending heavy black smoke into the afternoon sky. Lots of fire is rolling from the structure, plus there is a severe exposure problem with a nearby two-story converted single-family dwelling on the number 4 side.
The first engine is staffed with an officer, a driver/pump operator and two firefighters. The engine has slowed its response before arriving at the fire building, even though there is a lot of excitement and an urge to rush to do things. Firefighters are looking for a close-by hydrant to “catch” before arriving at the scene – the engine is going to perform a forward stretch (also called a forward lay).
A hydrant is spotted and the engine stops across from it. A firefighter takes the large-diameter hose (LDH) from the hosebed, a wrench and wraps the hydrant, then waves the engine on. The engine proceeds slowly toward the fire. At the scene, the officer tells the driver/pump operator to spot the engine for a deck gun operation and then radios in a well-involved two-story frame structure fire with a frame exposure problem. Other fire companies will be arriving in a few minutes.
The pump operator stops the engine at the designated spot, applies the brakes and engages the pump. The other firefighter on the company gets out, disconnects the LDH and hooks it into the pump’s large-diameter intake. The pump operator then radios the hydrant firefighter to charge the supply line as soon as he can and opens the air bleed. The officer has climbed on top of the engine, swings the deck gun into position and calls for water. The pump operator starts water from the engine’s tank and the water supply from the hydrant will be at the pump in seconds. The firefighter has been ordered by the officer to start stretching a 2½-inch handline with a solid-bore nozzle between the exposure and the fire building. He takes the working length and nozzle and begins taking the line while the pump operator helps him get the hose out of the bed.
The hydrant firefighter has rejoined his company and takes over stretching the 2½-inch handline for the pump operator. The pump operator has the supply line ready to feed the pump. The supply line is exhausted of air and then the intake is opened – a water supply is established. The two firefighters have stretched the 2½-inch handline into position and are calling for water. Their hose stretch is a 200-foot layout.
The pump operator reads his master gauges – his pump pressure for the deck gun is at 80 psi. His residual pressure is around 60 psi. He then opens the discharge for the handline. The pump pressure starts to drop as the firefighters flow water, so he builds pressure back up to approximately 75 to 80 psi while flowing. The deck gun has stacked tips and the 1¼-inch tip is being used now. The handline has a 11/8-inch tip. The water supply is adequate for both operations and knockdown is being achieved. The exposure is saved and the main body of fire is knocked down.
This small crew of firefighters accomplished several objectives early in this incident by good use of their equipment, using proper procedures and possessing a “can-do” attitude.
Getting Water To the Attack Engine
The forward stretch is used routinely by many fire departments for getting water from a source (hydrant) to an attack engine. When employed properly, it provides an engine company with a quick, secure water supply and flexibility in fire attack operations. This evolution is especially effective in the early stages of an intense and/or growing incident. It lets an engine be positioned with its hose and equipment near a fire building or incident with an established water supply.
This operation is different from a reverse stretch, where an engine company arrives at a working fire and drops its attack hose (and tools) at the fire and then takes off to a nearby hydrant or water source with hose trailing behind the engine. The pump operator in a reverse lay makes all the hookups unless help is available. The “reverse” pumping engine then pumps water back to the fire. The forward stretch is also not like an “attack” engine that responds to a fire and begins the fire attack with water from its booster tank while a supply line is hand-stretched to a nearby hydrant or where a second engine supplies the attack engine with water in a relay.
In its simplest form, the forward stretch involves an engine company locating a hydrant before arriving at a fire scene; having one firefighter get off the engine with a supply hose, a hydrant wrench and any other tools necessary for making the hookup; “wrapping” the hydrant with the supply hose, and then signaling the engine to proceed to the fire or address. When the engine is in its proper or selected fireground position, the supply hose is then broken and hooked into a pump intake. Once that is done, the “call for water” is made to the hydrant firefighter, the line is charged and the water supply is established.
What Works & What May Not
In short, the forward stretch is used to quickly establish a water supply and can help firefighters start a fire attack and keep it going without interruption of water. This procedure has its pros and cons, and we will look at some of each. Maybe your department has a few of its own.
One pro has already been mentioned – that is where the engine stops and secures a water supply before reaching the fire and then finishes responding to the location with the supply hose being laid or “stretched” as the engine moves forward. When the engine stops on the fireground, the pump operator (or another firefighter) breaks the supply hose coupling, hooks it into a pump intake and makes a call for water to the firefighter at the hydrant. That firefighter acknowledges the call and turns on the hydrant fully. When water reaches the pump, the supply is established.
Some fire departments perform the forward stretch with one added feature – after positioning the engine at a fire that is going to be fought using handlines, the initial attack line is stretched into position as quickly as possible and is charged with water from the booster tank. This is an excellent evolution that provides quick water application on the fire while the hydrant supply is being secured. Once the water supply is established, the pump is switched over to hydrant supply. Now, other attack lines can be stretched as needed. Any extra or unused water can be used to refill the engine water tank.
Keep in mind that the volume of an engine’s booster tank water supply must be watched during initial attack operations so as not to run dry before the hydrant supply arrives. A good rule of thumb is to charge only one handline for tank capacities of 750 gallons or less. (Note: That is predicated on the size of attack hoseline used, preferably 1¾ inch, and if a fire department meets or exceeds target flow in their attack lines or if it uses high-volume nozzles.)
If an engine arrives at a large fire that needs to be hit with a big amount of water, as from a deck gun, the engine performing the forward lay should first be positioned (with exposures in mind) for the best possible stream advantage and then supplied from a hydrant. Once the water supply is received, the heavy-stream attack can begin. By this method of supply hose stretch, your engine can start “big water” and keep water flowing without interruption, rather than using booster-tank water, as it would most likely be used up very quickly. However, if your engine is equipped with a large water tank, you can darken down a lot of fire, especially if your stream is well placed. Also consider the size of your solid-stream tips and how many gallons per minute they deliver at 80 psi.
One “con,” or downside, of the forward stretch occurs when an engine responds with less-than-adequate staffing (for example, one officer, one pump operator and one firefighter.) In this case, the firefighter making the hydrant hookup leaves the pump operator and company officer temporarily shorthanded to do the work of supply line hookup. The officer and pump operator will hook up the supply hose and may stretch an attack hoseline in the initial stages of fire operations by themselves.
Another con concerns a limited-supply water system. Where a community has a water system with small mains, small hydrants, dead-end mains and/or hydrants spaced at long distances, this can severely limit available water from a hydrant. This can be a serious problem where a large fire occurs in a remote setting and few hydrants are available, resulting in long supply hose stretches and excessive friction losses. In such cases, it is prudent to hook a supply engine to the hydrant, pumping into the supply hose pushing water to the attack engine.
In older neighborhoods, when several engines are performing forward stretches, they may experience reduced intake volumes because too many engines are drawing from the same grid source. It may be best to find the largest-volume hydrants and establish relays for maximum volume.
Steps for Implementing A Forward Stretch
1. Know your district or community and its characteristics – This is imperative and is an old axiom of the “job.” Firefighters in the past were always expected to know their districts. The senior firefighters of today should have been taught this by their senior firefighters years ago and should be passing these little tips on to their less-senior members. If you know your community, then you should know where the good water supplies and the bad water supplies are located.
If you work with other fire departments on a regular automatic-response system or mutual aid system, meet with everyone you will work to see how compatible your water systems are. You also want to look at your engines and see what size hose and couplings your neighbors are using. The worst time to find out your hose is different from your neighbors’ and no one has any adapters to overcome differences is when the fire is burning everything in front of you and you are powerless to get an effective attack moving!
2. Know your available water system, including fire hydrant locations, volume and pressure – Some municipalities have hydrants located every couple of hundred feet, while in some localities the spacing is much greater. In any case, it’s hard for everyone to know the water system. Some fire departments have developed hydrant, or “plug,” books that show all hydrant locations and their available water volumes. Departments with mobile data terminals (MDTs) in apparatus cabs entered this information in their data systems and locate hydrants by computer maps while responding. It is important to know your volume and flowing pressure from your system and the distance between your hydrants.
Do you have hilly terrain? If you have limited water availability and a hillside fire, an engine company stretching uphill will encounter the same elevation loss as if the water was going straight up as in a building standpipe. If you have this potential problem in your community, train now to overcome it. It may be as simple as setting an engine “on a hydrant” to push water to the fireground.
3. Use large-diameter hose (LDH) for supply purposes – Not that long ago, many fire departments were using supply lines consisting of 2½-inch hose. Today, LDH is the norm. Four- and five-inch hose appear to be the most popular sizes and are the most efficient at moving large volumes of water over long distances. (Some departments use six-inch hose, but it is not common; it is found in many industrial fire departments because of their particular threat potential.) However, it should be understood that even with LDH on your engines, there is still the factor of friction loss to consider, especially if you must make long stretches.
Many fire departments moving from smaller supply hose thought all of their water supply problems would go away with LDH This is not true. An example of this was illustrated by a fire department that routinely did forward stretches with 2½-inch hose, but moved to four-inch hose – a good move for that department. But the members did no homework or training on their new hose nor did they suspect anything other than fantastic water at every fire. At a large fire one night, they set their tower ladder (capable of discharging 1,500 gpm) at approximately 70-foot elevation being supplied by a single line of four-inch hose from a hydrant on an old water main 400 feet away. No engine was attached to the hydrant – it was a straight lay. Firefighters were puzzled when they could not get anything resembling a fire stream working. Fire departments must study their own conditions and determine what size and how much hose should be used in each system.
4. Train your officers and your firefighters – It gets repetitive, but it’s true. We don’t train enough. Because of the conditions found in many fire departments with small budgets and cutbacks, reduced staffing, working with different personnel (some departments staff their firehouses with combination crews), overtime and, yes, even working with other fire departments through mutual or automatic aid, we lose time to train on the basics of the job. There is a real need to understand the characteristics of the evolution and how to make it work – and how to overcome any problems out in the street and still get maximum flows. If your department works with other fire departments, meet with them and train with them. The worst time to find out that “this fire department has a different-size hose” or “that fire department has a different type of thread size” and that no one has any adapters to overcome this problem is at the scene of a major incident!
This article comes from the archives of Firehouse magazine. To read more magazine archives, click here to subscribe.