1.0 — Position on hydrant & establish own water supply

"The Engineer must recognize the need for and initiate supply line operations when required. When arriving other than first due, the Engineer must remain aware of water supply needs of units already on the scene."

The manual names three tactics the Engineer must be capable of performing: forward lay, reverse lay, and FDC supply. This evolution drills the first of them, on your own.

Where to put the rig

"The Engineer should position the apparatus for a Forward Lay whenever the need for water supply is determined. A hydrant in the immediate vicinity of the fire building may be used if it allows for a rapid stretch and will not interfere with ladder company positioning."

The manual repeats the constraint for hose stretches: the apparatus should be positioned so that it will not interfere with Truck Company operations.

What the connection is made with

"When performing a Forward Lay, the connection shall be made using 5″ LDH, in the event the 5″ LDH connection cannot be secured on the hydrant a minimum of 2-3″ hoses shall be connected, one on each side of the hydrant."

Pony lines are acceptable where connections are short, as long as the “5″ LDH first” rule is applied.

What you have to know once it is flowing

"In order to establish and maintain proper pumping pressures, all Engineers must know how many hoselines, the size and length of the hoseline, the type of nozzles being used, and their flow… They should also monitor the residual pressure of the pump master intake gauge to determine the capability of supplying additional volumes when available or as needed."

Engine Company Operations 2023 V-1, Firefighter Assignments, pp.1-9–1-11, figs. 1-1 and 1-2

Hydrants are the easiest source of water for an engine company, and the primary hydrant to expect is the dry-barrel. The standard hydrant has one 4½″ (steamer) outlet and two 2½″ outlets; commercial or high-occupancy areas may have hydrants with two steamers. Three basic components: barrel, discharge outlets, and stem (shut-off valve). All outlets carry National Standard Threads (NST) per NFPA, in 2½″ or 4½″.

When the stem valve is closed, the barrel is empty from the top of the hydrant down to the water main — the main valve sits below the frost line, which keeps water out of the barrel. When the stem opens, water supplies all outlets at the same time.

"It is important to remember, when a dry-barrel hydrant is charged no additional lines may be added to the other outlets unless the hydrant is shut down or a shut off valve is added prior to charging."

Common dry-barrel hydrants in Orem's response area: Mueller Centurion, Waterous Pacer, and Kennedy Guardian — the makes the current city code allows. There are also double 2½″ hydrants (no steamer, fed by a 4″ main, expected flows under 600 gpm), and a few privately owned hydrant systems whose maintenance and repair are the responsibility of the HOA or business owner.

Engine Company Operations 2023 V-1, Water Supply, pp.5-1–5-4, photos 5-1 to 5-5

Stem valve rotation

"The nationally recognized direction to open hydrant stem valves is counter-clockwise (“Open-Left”). All water districts and municipalities that surround the City of Orem follow these standards."

Basic hydrant flows

How much water a hydrant gives varies with main size, system pressure, and how many hydrants are being worked off the same main at once. The manual still gives figures you can rely on:

• A single 5-inch line may not flow all of the available water from a hydrant and/or water main.
• Provide one 5-inch hose line for every 1000 gpm to be delivered.
• A 2.5″ hydrant outlet delivers approximately 80% of the flow of a 4.5″ outlet.
• A 4.5″ hydrant outlet with a flow pressure of 15 psi = 2100 gpm.

This is the reason step 5 puts gate valves on both 2½″ outlets before you charge: the steamer alone may not be the whole hydrant.

Engine Company Operations 2023 V-1, Water Supply, p.5-5

The hydrant bucket/bag stores the tools and adapters needed to complete a hydrant hook-up, and rides in the rear compartment. Depending on arrival order and the type of supply lead, either the 1st due or 2nd due engine leaves it and its contents at the hydrant. Contents:

• Screw handle hydrant wrench — opens and closes the hydrant on the bonnet nut; double claw sides for coupling lugs
• 5″ Storz × 2.5″ female — connects a 5-inch supply line into a 2.5″ hydrant outlet
• 2.5″ and Storz spanner wrenches — tighten and loosen hose couplings and valves
• Two 2.5″ hydrant gate valves — attached to the 2.5″ outlets when additional GPM is required
• 2.5″ double-female — for a hydrant outlet when a 3-inch supply line is used
• Rubber mallet — for loosening stuck hydrant caps and hoseline couplings

Engine Company Operations 2023 V-1, Water Supply, p.5-6, photo 5-6

"A Forward Lay is a supply line evolution that starts with the laying of a hose-line from a hydrant / water source, and proceeds to the fire (hydrant-to-fire)."

The engine stops at the hydrant, “lassoes” the LDH around it, and drops the supply line toward the fire building. It is typically done by an engine company providing its own water supply — which is what this evolution is — or by one company supplying another already on scene. Depending on the lead the officer selects, the Back-Up firefighter can be left at the hydrant to complete the connection.

Two operational modes for the LDH lead

• The “wet” lead — the Back-Up firefighter remains at the hydrant and charges the line when the command to do so is received.
• The “dry” lead — the Tailboard firefighter anchors the hose, leaves the hydrant bucket, and proceeds to the fire with the crew; other personnel are assigned to charge the hydrant.

Engine Company Operations 2023 V-1, Water Supply, pp.5-7–5-8, figs. 5-7 and 5-8

"The reverse lay option may be employed by either the first due engine or the second due engine and occurs when the engine arrives at the fire building first and then proceeds to the hydrant location."

This can be advantageous because it places the engine at the source of the water, so that engine can supplement the pressure from the hydrant to the engine that ends up in front of the fire. Two sub-types:

• Supply evolution — LDH connected between the suction side of the pump and the hydrant.
• Attack evolution — LDH connected between the discharge side of the pump and an appliance or master stream.

Engine Company Operations 2023 V-1, Water Supply, p.5-9, fig. 5-9

The third option. The first due engine may have to place the apparatus somewhere with no water — a cul-de-sac, a limited-access apartment complex, a commercial structure whose supply sits out on the main thoroughfare. The company officer drops LDH at the entrance to the area they will be operating in, and must transmit the intention to start a split lay.

The second due engine completes the split: depending on their direction of travel relative to the split, they either lay out from the split to the hydrant, or lay in from the hydrant to the split.

Engine Company Operations 2023 V-1, Water Supply, pp.5-11–5-12, figs. 5-12 and 5-13

Three basic tactics for getting the most water out of a distribution system, listed by the manual from least preferred to best preferred:

• Multiple supply lines from a single hydrant.
• Pumping the hydrant with the 2nd or 3rd due engine supplying the attack pumper.
• Multiple supply lines from different hydrants sharing the same water main.
• Multiple supply lines from different hydrants not sharing the same water main.

Read backwards, this is the argument for step 5: the gate valves you hang on the 2½″ outlets at the onset are what make the first of those tactics possible later without shutting the hydrant down.

Engine Company Operations 2023 V-1, Water Supply, p.5-13, photos 5-14 to 5-17

"Regardless of arrival order, or whether a Tailboard firefighter is staffed the BackUp Firefighter is responsible for the hydrant connection on a forward lay."

On the 2nd due engine at a working fire the same rule holds for both lays: the back-up firefighter is responsible for the hydrant connection on a forward lay or reverse lay. For LDH hose work the manual gives one instruction:

"Hand jack LDH back to the plug and complete the hydrant connection for water supply operations."

So as Engineer you are not making this connection alone by default — but this evolution drills you to establish your own supply, so you own every step of it here.

Engine Company Operations 2023 V-1, Firefighter Assignments, pp.1-23–1-24, photo 1-11

Task #19 is the skill behind out-of-cab steps 7–12 above: moving the pump from tank water to a pressurized external source — a hose-line supplied by another apparatus, or a hydrant. Its operating procedure, verbatim:

• Step 1 — Position the apparatus in a safe position, and immobilize it by setting the parking brake and chocking the wheels.
• Step 2 — Engage the pump, and select the proper gear in the road transmission. Lock the gear into place.
• Step 3 — Open the tank-to-pump valve (if necessary).
• Step 4 — Set the transfer valve to the series (to PSI or RPM) position depending on application.
• Step 5 — Increase the throttle setting to obtain the desired pressure, priming (if necessary).
• Step 6 — Set the relief valve or pressure governor.
• Step 7 — Open the circulator valve or partially open the tank fill valve.
• Step 8 — When an external supply becomes available, open the intake valve while closing the tank-to-pump valve (if necessary). As soon as an adequate supply of water is available, divert enough of it through the tank-fill line to replenish the supply in the tank.
• Step 9 — Adjust the engine throttle to achieve the desired discharge pressure (if necessary).

Note the tank-fill valve: Task #19 says it "should be left partially open until the water tank has been refilled" — which is what printed step 12 is asking for.

One control caution: the task book's PSI mode button and Task #19's transfer valve are different controls, not two names for one action. PSI/RPM mode is a PUC feature — among Orem's pumps it is on Engine 34 only.

ADO Task #19 — Basic Pump Skills, Changeover (Transition to an External Water Supply); rig-specific control per department review, 2026-08-30

This is what printed step 11 is for. Orem's method for judging how much more water a hydrant has left is the 1st Digit Method: take the first digit of the intake (residual) pressure and multiply it by 1, 2 and 3 to set the brackets. The manual prints it worked at a 90 psi intake:

• 90 × 1 = 9 — a residual drop (R-difference) of 1–9 psi = 3 more like volumes remaining
• 90 × 2 = 18 — a drop of 10–18 psi = 2 like volumes
• 90 × 3 = 27 — a drop of 19–27 psi = 1 like volume
• A drop of 28 psi or more = 0 like volumes

Do not carry 9/18/27 to a different hydrant. Those numbers come from the 90 psi intake the manual worked the example at. On an 80 psi intake the brackets are 8/16/24. The rule is the first digit × 1, 2, 3 — not the numbers.

And it is a check on a gauge, not a licence to add lines on arithmetic alone: the manual pairs it with the standing instruction to monitor the residual pressure on the pump master intake gauge (Engine Company Operations p.1-11).

OFD Hydraulic Manual, §4 “Calculating Like Volumes” — 1st Digit Method with 90 intake pressure