“Hey, catch that hydrant” is probably the best phrase to hear in the fire service. Those four words solidify the fact that you are about to go to work. The necessity of a reliable water supply makes that job so much easier. If only those four simple words were uttered at every job. Reality sets in at this point.
It’s 3:00 a.m., and you find yourself on a backcountry road with a livestock barn rocking. No hydrants are in sight, the driveway is 800 feet long, and your next due is a tanker with 2,000 gallons of water to add to the 750 in your booster tank. You find yourself laying in with your large-diameter hose and stretching 2½-inch lines either directly hitting the fire or providing a water curtain to protect exposures. Your 750 gallons of tank water are gone in a matter of minutes. All the while, that next-due truck, the tanker, is dropping portable tanks or setting up the rural hitch at the end of the driveway.
This all seems fine and dandy, but now what? You are 800 feet down this driveway and your only hope for water is sitting in a portable tank at the other end of the drive. Let’s hope the third truck to arrive is an engine capable of pulling a draft from a portable tank and supplying the first due.
Hydrant Review
Catching a hydrant is likely one of the most rehearsed and crucial roles of a firefighter. Capturing that needed water supply is of the utmost importance. Wet vs. dry barrel doesn’t even matter at this point. You have a solid, pressurized water source that will hopefully suffice for the fire at hand.
But, what if you don’t have a plug to catch? What if there are no pressurized hydrants in your first due? Welcome to rural water supply!
Most structural fires in a metropolitan area are handled by engine, ladder, and rescue companies. In the rural setting, that is not always the case. Rural fire departments don’t necessarily have the same resources available—and for good reason. The likelihood of a rural department owning and operating an aerial apparatus or a rescue is at times farfetched when water supply is crucial. Water tankers/tenders are the common apparatus found in the rural setting. They allow you to establish and hopefully maintain a coordinated water supply.
1 A dry hydrant. (Photos by author.)
In the rural setting, there are water supplies; they come in the form of ponds, lakes, and other static sources. There are two main concepts to acquiring water from these sources. The use of a dry hydrant is ideal, but the use of a floating strainer is also a practical option if no dry hydrant is available.
Dry hydrant. A dry hydrant is a simple concept involving, in most areas, simple polyvinyl chloride (PVC) pipe, a strainer, threaded or cam-lock connections, and a body of water. Typically, 6-inch PVC pipe is installed underwater, resting on the bottom of the body of water with a strainer on the end. The pipe then continues underground and pops through the ground at an access point for an apparatus to make a connection to. The connection point is traditionally either standard 4½-inch threaded or an equivalent cam-lock setup. At this point, you can draft from this dry hydrant from its static source.
Floating strainer. At times, a body of water may not have a preestablished dry hydrant set up for use. You can overcome that obstacle with ease using basic drafting equipment and principles. Equipment used in this process is similar to that used with a dry hydrant except adding in a floating strainer.
Hauling Water
Whatever the verbiage, tanker or tender, you need to get water to the fire. You have your water source ready, whether a preestablished dry hydrant or just a simple static source. Now what? How are you supposed to get that water to the fire scene? The answer is simple: with basic drafting principles and equipment.
2 A hard stick to a portable tank.
Let’s start with equipment—an apparatus capable of drafting, a hard stick (the length varies), and a low-level strainer if no dry hydrant is available. Traditionally, with conventional tankers, an engine is required at a fill site to pull a draft and pump water to the waiting tankers. However, some departments have transitioned to a hybrid tanker known as a vacuum (vac) truck. These hybrids work off the basic concept of creating a vacuum to fill a void space. The vac trucks have quicker filling capabilities because of their ability to create negative pressure. Regardless of traditional tanker vs. vac truck, you have a means to haul water.
Drafting Basics
The engine shows up to the fill site and is ready to set up. The operator puts the pump in gear and sets the chocks. The jump seat firefighters grab whatever lengths of hard stick they need to reach the dry hydrant or enough hard stick and a low-level strainer to reach the water if no hydrant is present.
Now, basic drafting says that any air in the system will not allow the engineer to properly pull a prime and effectively draft. Tight connections are a must, and a rubber mallet often ensures connections are tight. You now have a tight connection to your truck’s intake as well as to the hydrant itself or from the truck’s intake to the strainer submerged in the water.
3 A hard stick with tight connections and closed valves and drains.
Make sure all valves are closed, caps are tight, and drain valves are closed. If you don’t check the truck and make certain things are closed and tight, you will introduce air into the system and create issues drafting. A rule of thumb when drafting is to idle your revolutions per minute up to roughly 1,000 before obtaining your draft. Whether fitted with a manual primer or an auto primer, trucks must be in proper working order to achieve the end result. Pull the primer or switch on the auto primer to begin the process. Remember, you are not necessarily sucking water but rather lifting water from the source to the pump.
Now comes the part of the process where your senses need to be sharp. You can visualize and hear that you have achieved prime and created a draft. If the hard stick is translucent, you will be able to see the water moving up the stick and into the pump. By listening to the primer in action, you can easily deduce that you have achieved a draft when you hear a bogging down of the system. If you see it and hear it, you likely have pulled a draft and have an established water supply.
You can also use gauges to judge the effectiveness of the drafting attempt. As air is displaced and water is introduced to the pump, the intake pressure will rise, and the vacuum pressure will remain at zero. If you encounter issues, restart the process. Likely there is air being introduced to the system somewhere; simply close a valve or drain, and you will be in business.
At this point, your fill site is up and running completely and able to supply tankers with water to haul to the fire scene. The vac truck eliminates the need for an engine at the fill site; it can create a vacuum to fill the tanks instead of relying on, in essence, a relay pumper.
Back at the Barn
Now that you have secured a water source and can shuttle water to the scene, you can effectively mitigate the fire. The portable tanks that were dropped at the end of the driveway are now in action. As tankers are offloading their water, you have established a steady water supply needed for suppression. The next-due engine can simply act as a relay pumper drafting from the portable tanks to supply the first due’s suppression efforts.
The amount of work and effort firefighters put into battling a fire is intense, to say the least. When water supply is as simple as catching a hydrant, that workload can decrease considerably, not to mention freeing up much-needed staffing and resources. When water supply becomes complicated and there is no hydrant to catch, not only does the workload increase, but the need for increased staffing and resources skyrockets.
At the end of the day, we all have our water supply issues. Some are minuscule in comparison to others but, overall, we will prevail.
Thomas Gross is a captain and training officer with the Seville-Guilford (OH) Fire Department and a firefighter/paramedic with the Central Fire District in Smithville, Ohio. He is a first-generation firefighter with 15 years of experience. He has a Firefighter 2 certification as well as paramedic, fire instructor, and emergency medical instructor certifications.
