Several articles ago, we discussed the initial response to an emergency call, and stated that in future articles we would examine other response considerations in greater detail. This month, we will be giving an introduction to Water Supply operations. Water supply for fire suppression operations is both at the same time rather simple, yet can become extraordinarily challenging and complex depending on the situation.
In order to grasp the concept of water supply, it is first important to review some basics of fire science. The Fire Triangle refers to the basic requirements for a fire to start and burn, and consist of the following three elements: Oxygen, Fuel, and a Heat Source. All three of those components must be present for a fire to start and burn, and in order to extinguish a fire, a minimum of one of those elements must be removed from the equation. The majority of the time, fire suppression attempts to eliminate the heat source by cooling the fire. Most often, this is done through the use of water, though at times chemical foam agents are used to accomplish the same goal.
There are two basic ways in which the fire department can access water for fire suppression. The first is a municipal (city) system that consists of utilizing the existing municipal water supply that is accessible through fire hydrants. This is a relatively simple process, where we connect directly to existing water supply. If the system is working properly, we generally have a consistent and secure access to a suitable water supply. One unique challenge, as we approach winter, is when a hydrant freezes and we cannot gain access to the water. Another winter concern is when hydrants are covered by snow, or blocked by piles of snow. This increases the chance that the hydrant can be frozen and inoperable, as well as adds up to several vital minutes on to our response while we have to remove the snow from the hydrant to gain access.
The second way involves what is referred to as rural water supply. In this scenario, the fire department is required to haul all the needed water to the fire scene from a fire hydrant in the city. Depending on the nature of the fire, such as a large barn fire, the amount of water that must be hauled (or “shuttled” as we often refer to it) can be substantial. In the fire services, there are several different types of apparatuses (trucks) that are used to accomplish fire suppression. Engines are used to actually pump the water on to the fire and carry a limited amount of water in their internal tanks. For smaller fires, such as a vehicle fire or fire limited to one room of a building, this is often enough water to accomplish the task. For larger fires requiring more water, tenders are used to haul large amounts of water to scene. Depending on the size of the tender, 1-3 thousand gallons can be hauled at a time. At one time, and you may still hear this on occasion, tenders were commonly referred to as tankers. Now, with the Incident Command System, the term tanker is reserved for the large aircraft that are sometimes used in forest fire situations.
Upon arriving at the scene, tenders can either pump water directly in to an engine, or empty the water in to a large drop tank that is similar in some ways to a small swimming pool. What makes rural supply challenging is that the officers in command at the scene must account for the amount water being used in suppression, and then account for the travel and refill time it takes for a tender to return to a fixed water source to refill. In the event that multiple hose lines or engines are being used in the fire attack, several thousand gallons can be used in just a matter of minutes. It is always very important to keep a reserve of water in place in case of an emergency, so we never want to use all the available water at the scene.
In order to keep enough water moving to the fire scene, most departments rely on mutual aid from other departments that provide tenders and crews to haul water to the scene. In a rural area our departments work very closely with each other to maximize our collective resources. Fennimore is surrounded by excellent departments that we often rely on for this type of assistance when we have a rural fire in our district. Another way that we have increased our rural water supply capabilities is through the use of dry hydrants. These are used to pump water directly out of streams to resupply our tenders, and Fennimore has two such hydrants. One is located on Collins Road and the other is located on County Q near Castle Rock.
In order to grasp the concept of water supply, it is first important to review some basics of fire science. The Fire Triangle refers to the basic requirements for a fire to start and burn, and consist of the following three elements: Oxygen, Fuel, and a Heat Source. All three of those components must be present for a fire to start and burn, and in order to extinguish a fire, a minimum of one of those elements must be removed from the equation. The majority of the time, fire suppression attempts to eliminate the heat source by cooling the fire. Most often, this is done through the use of water, though at times chemical foam agents are used to accomplish the same goal.
There are two basic ways in which the fire department can access water for fire suppression. The first is a municipal (city) system that consists of utilizing the existing municipal water supply that is accessible through fire hydrants. This is a relatively simple process, where we connect directly to existing water supply. If the system is working properly, we generally have a consistent and secure access to a suitable water supply. One unique challenge, as we approach winter, is when a hydrant freezes and we cannot gain access to the water. Another winter concern is when hydrants are covered by snow, or blocked by piles of snow. This increases the chance that the hydrant can be frozen and inoperable, as well as adds up to several vital minutes on to our response while we have to remove the snow from the hydrant to gain access.
The second way involves what is referred to as rural water supply. In this scenario, the fire department is required to haul all the needed water to the fire scene from a fire hydrant in the city. Depending on the nature of the fire, such as a large barn fire, the amount of water that must be hauled (or “shuttled” as we often refer to it) can be substantial. In the fire services, there are several different types of apparatuses (trucks) that are used to accomplish fire suppression. Engines are used to actually pump the water on to the fire and carry a limited amount of water in their internal tanks. For smaller fires, such as a vehicle fire or fire limited to one room of a building, this is often enough water to accomplish the task. For larger fires requiring more water, tenders are used to haul large amounts of water to scene. Depending on the size of the tender, 1-3 thousand gallons can be hauled at a time. At one time, and you may still hear this on occasion, tenders were commonly referred to as tankers. Now, with the Incident Command System, the term tanker is reserved for the large aircraft that are sometimes used in forest fire situations.
Upon arriving at the scene, tenders can either pump water directly in to an engine, or empty the water in to a large drop tank that is similar in some ways to a small swimming pool. What makes rural supply challenging is that the officers in command at the scene must account for the amount water being used in suppression, and then account for the travel and refill time it takes for a tender to return to a fixed water source to refill. In the event that multiple hose lines or engines are being used in the fire attack, several thousand gallons can be used in just a matter of minutes. It is always very important to keep a reserve of water in place in case of an emergency, so we never want to use all the available water at the scene.
In order to keep enough water moving to the fire scene, most departments rely on mutual aid from other departments that provide tenders and crews to haul water to the scene. In a rural area our departments work very closely with each other to maximize our collective resources. Fennimore is surrounded by excellent departments that we often rely on for this type of assistance when we have a rural fire in our district. Another way that we have increased our rural water supply capabilities is through the use of dry hydrants. These are used to pump water directly out of streams to resupply our tenders, and Fennimore has two such hydrants. One is located on Collins Road and the other is located on County Q near Castle Rock.
It is our hope that you have a better understanding of why and how we use water to fight fires. Until next time, stay safe and try to stay warm during these cold months.
