A course in pump station hydraulics

Head, Loss and Lift

A hydraulics course in pump station design for sanitary sewage and potable water — head loss, hydraulic profiles, pump selection and the details that decide whether a station works.

Water only moves downhill. A pump station is where the ground stopped cooperating, and every element in it is an answer to a specific failure.

8 modules43 lessons43 instruments, every one verified37 concept pages

The descent

Each stratum answers one question and is honest about what it is still treating as a black box. Read down: nothing below is needed to understand anything above it, and nothing above is safe to apply until you have been below it.

Stratum 0system

The station as one object

What is this thing, and why does it exist at all?

What you get
The whole hydraulic chain, in order, with names. Two liquids and two problem sets. What capacity you can actually rely on.
Still a black box
Every number. Nothing is calculated yet — this stratum only makes sure you know what the parts are called and what each one is answering.

0/5

Stratum 1principle

The one equation

What conserved quantity is a pump station bookkeeping?

What you get
Energy per unit weight — head. Elevation, pressure and velocity as interchangeable currency. Total dynamic head assembled from its terms.
Still a black box
How big the loss terms are. You will know that friction belongs in the equation before you know how to size it.

0/5

Stratum 2subsystem

Where the head goes

How much energy does the pipework take, and how do I draw the proof?

What you get
Darcy-Weisbach and the Moody chart. Hazen-Williams and its traps. Fittings, valves and entrances. Then the hydraulic profile that puts all of it on one drawing.
Still a black box
The pump. Here it is a black box that supplies whatever head the system demands — which is exactly the assumption Stratum 3 destroys.

0/15

Stratum 3component

Inside the machine

What can a real pump actually deliver, and where will it sit?

What you get
How a pump makes head. Reading a curve. Specific speed, NPSH, the affinity laws. Then matching the pump to the system and optimising against lifecycle cost.
Still a black box
The mechanical detail of the station around the pump — the wet well, the valves, the controls that decide when it runs.

0/12

Stratum 4detail

The details that decide it

What makes a hydraulically correct station fail in service?

What you get
Wet well cycling and submergence. Screening and solids. Check valve slam and surge. Controls, alarms and the failure modes that show up years later.
Still a black box
Nothing. This is the stratum where the black boxes run out, which is why it is last and not first.

0/6

Field notes

The quirks: unit traps, coefficients that silently assume a pipe size, standards that disagree, and the mistakes that survive peer review.

Final examination

A station sized end to end — flows, losses, profile, pump, NPSH check, and a defence of the choices.