When attempting to support large fire flows using multiple dump tanks and large tankers, we generally find that the dump tanks need to be spaced out some in order to allow two tankers to offload simultaneously - this need becomes more and more apparent as we approach that 1,000 gpm flow. One "best practice" is to put some space betwen two dump tanks and span that space with an attic ladder or roof ladder. Both of these ladders are probably going to be present on the dump site drafting pumper - so it easy to grab one and use it. Of course, some suction hose will be needed to "stretch" the jet-siphon transfer line - but that is why you carry 40-feet on a rural pumper and carry suction hose on tankers.
At this 2006 water supply drill in Lineboro, Maryland, the third dump tank was set-up to allow space between it and the others. The space was spanned by a roof ladder (from the yellow pumper) and the suction hose was grabbed from the white tanker. The result - the ability for two, 3,500 gallon tankers to side dump on this rural road while supporting a 1,000 gpm fire flow.
Of course - the success was in the "planning phase" of the dump site set up. Crews knew what was needed in order make the site a success and carried that plan out.
