Treadle Pump — Irrigation by Foot

Groundwater sat just metres below the fields — but without power or fuel, farmers couldn't reach it. The answer was a pump you drive with your own legs.

At a glance

•      Origin: northwest Bangladesh, late 1970s — engineer Gunnar Barnes with the Rangpur Dinajpur Rural Service (RDRS); scaled by Paul Polak's iDE.

•      Maturity: Scaled — over 1.5 million sold in Bangladesh alone; replicated across Asia and Africa.

•      Energy: none but human. Powered like a StairMaster — the rhythm of your legs drives the pistons.

•      Licence: Open — the core design is not patented.

The story

In northwest Bangladesh in the late 1970s, small farmers faced a cruel paradox: groundwater lay a few metres beneath their feet, but without electricity or fuel they couldn't reach it. In the dry season, crops failed — and landless farmers rented water from big landholders at prices that kept them poor.

A Norwegian engineer, Gunnar Barnes, working with the RDRS, built the first treadle pump — a foot-powered device that used the weight and rhythm of a person's legs to drive pistons and pull water from shallow aquifers. Then, in the early 1980s, Paul Polak of iDE saw it and recognised the real gap: the technology existed, but the market didn't. iDE built the network of local manufacturers, dealers, and installers that could put the pump in farmers' hands at a price they could actually afford.

Over 12 years, 1.5 million pumps were sold in Bangladesh. The programme cost $12 million (12 000 000) — where conventional dams and canals to irrigate the same land would have cost around $1.5 billion (1 500 000 000). During the programme, farmers earned an estimated $150 million (150 000 000) a year in additional net income — a figure reported by Paul Polak and carried in iDE’s own account.

It changed more than economics. Where large landholders had monopolised water and charged high fees, the treadle pump gave small farmers their own source — quietly restructuring who held power in the village.

The problem it solves

Smallholder farmers with shallow groundwater but no electricity or fuel can't irrigate in the dry season — so crops fail, or they pay exploitative rates to rent water from those who can pump it.

The treadle pump turns a person's own effort into reliable irrigation, at a price a small farmer can own outright.

How it works

The user stands on two treadles and steps as if climbing stairs. That motion drives two pistons in cylinders; the pistons create suction that lifts water up an intake pipe, and pushes it out through a delivery pipe to the field or channel.

It's a suction pump, so it works best where the water table is within about 7 metres of the surface. The original could be built largely from bamboo and local materials; sturdier manufactured metal versions last longer.

What to expect — and what not to

A capable pump for shallow-water smallholdings — a person can irrigate roughly half an acre to an acre depending on conditions.

•      Needs groundwater within reach of suction (about 7m) — deeper water needs a different tool.

•      It is human-powered, so it takes real physical effort; output depends on how long someone can treadle.

•      Not a substitute for large-scale irrigation, and not suited to deep water tables.

When it doesn't work — the honest part

The honest limit is bodily: this runs on human energy, and there's only so much treadling a person can do in a day, especially in heat. It suits small plots, not large farms.

And its history carries the same lesson UnaMente keeps finding: the pump succeeded not because the device was clever but because iDE built the market and supply chain around it. A good tool with no way to buy, repair, or replace it doesn't spread. Plan for the supply chain, not just the pump.

Credit & licence

Original design by Gunnar Barnes with the Rangpur Dinajpur Rural Service (RDRS), Bangladesh; scaled through the market-building work of Paul Polak and International Development Enterprises (iDE). The core design is unpatented and open.

For the commercial-scale version, KickStart International makes the well-known MoneyMaker pump; the open DIY design is documented on Akvopedia.