RURAL FIRE COMMAND

Tender Tactics: Mobile water supply methods for the rural setting

Story & Photos By Keith Klassen

In many areas of the country, apparatus carrying large amounts of water to the scene are called water tankers. In fact, according to the National Incident Management System, tanker is the correct term for such a thing. But in the western United States, if you request a tanker to respond to your fire scene, you’ll need to look skyward—because what you’ll get is an airtanker, most likely carrying a load of fire retardant!

For what it’s worth, in the west, tankers are called water tenders. In this column, we’ll examine ways to use water tenders on the fireground.

Tenders & Tanks
One way to use a water tender: have the pumping engine nurse off the tender. In this operation, the tender effectively becomes an extended booster tank, connected directly to the inlet of the pump. An advantage to this operation: One operator can manage both apparatus.

The connection between the two apparatus must use some type of suction hose to prevent collapse as the pump creates a negative pressure. A clear flex hose is best because it will allow you to see air in the line and will allow for bends. The connection will most likely require two sections of suction hose, but ultimately this will be determined by the placement of the two connecting apparatus.

Note: The suction hose may need to be supported, particularly if large-diameter suction line is used, because the weight of the water in the line will place a lot of force on both the hose and couplings.

A second method is to drop a portable tank and fill it from the tender. The tank then becomes a water source from which engines can draft. An advantage here is that more than one engine can draft from the same tank.

Portable tanks come in a variety of sizes, as well as in frame-supported and self-supporting versions. Tank size and type will be determined by the space and location available on the apparatus to carry the tank and the type of operations for which it will be used. Generally speaking, structural departments favor the frame-supported versions, while wildland agencies use the self-supporting type because they are deeper, making them easier for helicopter bucket operations.

It’s a good idea to carry a tank that will hold the capacity of the tender. This allows the apparatus to empty its full load and immediately leave for a second load.

Setting Up
When placing the tank, look for a relatively flat area that is clear of objects that would damage the tank. Ensure there’s ample space around the tank for apparatus and personnel. Place the tank drain at the lowest point to facilitate draining the tank after the incident.

Tip: Place a volleyball in the tank during operations. As the tank level drops, the water movement at the end of the suction line will create a vortex that can draw in air and cause a loss of prime, but the volleyball will be drawn to the vortex and effectively prevent air from entering.

Another tool that can maximize the effectiveness of the tank: a low-flow strainer. It will allow the water level of the tank to be pumped down to within inches of the bottom and still provide full flow. Multiple tanks can also be set side by side and connected by hard suction hose, which will allow water to be siphoned between tanks.

Long Driveways
In the rural environment, long driveways are very common. To handle these situations, you may have the engine lay a supply line from the street up the driveway. If the tender is equipped with a pump, it can be used to relay pump from the tender to the pumper. This allows the two apparatus to be farther apart than if nursing, as discussed earlier, which can be advantageous if space on the scene is tight. The water tender can then remain on the street and pump the hose lay. This operation will require an operator at each apparatus to communicate their respective water pressures and levels and ensure water is constantly available.

As with any relay pumping operation, the objective is to simply move water to the apparatus pumping the fire. Although large volumes may be required, you only need enough pressure to overcome friction loss and provide a residual pressure.

An auxiliary-powered portable pump is one of the most effective ways to equip a water tender. Although a small pump can be useful, a 350–500-gpm pump is much more effective. A portable pump can be simply mounted on a quick-release bracket, or it can be both mounted and connected to the water tank. This second option is the most versatile, as it facilitates pump-and-roll operations, stationary pumping and easy removal for use as an independent pump.

Removing the pump and using it independently can be an effective tactic on a long driveway. Again, the engine lays a supply line from the street, and, upon arrival, the water tender drops a portable tank and fills it. The pump is also removed and set up as a portable pumping station, drafting from the portable tank and feeding the supply line. The water tender is then free to refill at the closest water supply and return, thus providing uninterrupted water for firefighting operations.

Conclusion
As you can see, there are many options available when it comes to mobile water supplies. How you supply water in your jurisdiction will be based largely on the storage space available on your apparatus, the unique features of your jurisdiction and the types of fires you most often encounter. Consider also how your strategies would change in a worst-case scenario. [Keith: I added these sentences and please edit/remove as you see fit] Be creative and examine the most effective ways to utilize your mobile water supply. The only limit is your imagination.

Keith Klassen is a career captain with the Summit Fire District, a rural combination department bordering Flagstaff, Ariz. He has 33 years of volunteer and career experience in both structural and wildland firefighting, and a background in mechanical and vocational education. Klassen is also an international fire service instructor.