On May 18th, the Lakes Region Mutual Fire Aid Training Division sponsored our 8-hr LDH/Relay Pumping Seminar at the Bristol FD. The seminar began with a classroom review of large diameter hose, relay pumping, and drafting practices. The seminar culminated in the afternoon with a 3,100 ft, 5-pumper relay pumping drill. Several tests were run using different pumping configurations and the participants got to see the effects of various discharge pressures on flow results in 4-inch hose. A complete summary will be posted in a few weeks. Instructors for the seminar were Mark Davis and Shane Darwick.
We are also pleased to report that the t-shirt raffle raised enough money for the 33rd brick in the NFFF Walk-of-Honor!
The beginnings of a 3,100-ft relay pumping operation with 4-inch hose.
Gilford FD's "Old Ironsides" Engine 4 (1,500 gpm) drafted from a pond using dual suction intakes in order to maximize flow.
A deck gun was used to keep circulation going at the "source" pumper until such time that the relay pumpers were ready to flow water. Then, the deck gun was shut down and a "trash line" was used to circulate water.
The older pumper did not have a LDH discharge - so two, lines were "siamesed" into one 4-inch line using a double-clappered siamese. This arrangement produced a 1,300 gpm flow capability.
A 4-way hydrant-assist valve was used as one of three, in-line relay devices in the 3,100 ft hose lay.
Bristol's Engine 4 is shown here pumping a Jaffrey Z-valve at the midway point in the hose lay. The Z-valve allows for a long hose lay to be completed and water flow started before a relay pumper arrives. Once the realy pumper arrives - they simply hookup to the Z-valve and become a "pumping station."
A HoseMonster flow diffuser was used to obtain accurate flow readings during the drill. Water was discharged back into a stream that was part of the source pond's overflow path.
Wenworth FD's Engine 1 (1,000 gpm) operated as the attack pumper at the end of the 3,100 ft hose lay. This pumper was the smallest capacity pumper in the relay event.
HoseMonster pressure reading converted to a flow using a cross-reference table. Flow was maximized at around 700 gpm.
