What would you rather do, dump the water off the tanker into a dump tank and get it back on the road to get more water or call in numerous tankers and have them tied up having them pump off into a pumper??? Just trying to get some input on what others do?? The Department i am on we set up dump tanks and dump and go on working fires.
We are a predominately rural fire district (525 sq. miles, 10 stations, 140 firefighters). Our hydrant locations are limited. As a result, we use our tankers for almost all of our structure fires!
Our primary objective is to drop folding tanks, dump the tanker quickly, and get it back on the road. All of the formulas used to calculate fire flow delivered by tanker seem to indicate that travel time cannot be reduced without compromising safety, The only way to improve water delivery is to shorten the tanker's fill time or the tanker's dump time. Fill time and dump time includes the time get the dump site set up or the fill site set up, service the tanker, and get the tanker on the road again. It is turnaround time that determines whether tanker shuttles are efficient or not.
Our standard response to structure fires is two stations (engine with 1000 gal tank and tanker with 2000 gal tank at each station, plus other vehicles for manpower). At most of our working structure fires, we set up two 2100 gallon folding tanks (dropped off by the first and second due tankers). The drafting engine uses a low-level strainer connected to flexible hard suction to draft with, and uses a second low-level strainer and flexible hard suction to move water between the two tanks. When possible, we dump into the 2nd tank so that dumping water doesn't disrupt the draft. All of our tankers have 100 sq inch quick dumping valves (one at rear, one on driver's side). If two tankers cannot keep up with fireflow demand, then additional tanker(s) are requested. At the edges of our district, we work with mutual aid districts, both giving and receiving assistance from other tankers.
We have quite a few pictures of our tanker shuttle operations on our district's webpage. Feel free to ask questions. I hope this helps!
Jeffery A. Hartle, CFPS, MIFireE
Johnson County Fire Protection District