Neglected for more than 150 years, the simple ram pump has the potential to bring water to areas of drought, and protect communities from flooding.
Ask people to name the invention most closely associated with the Montgolfier Brothers, and most would plump for the hot air balloon.
But while this may remain the 18th century French pair’s most famous claim to fame, they also developed something which, over time, may prove to be even more celebrated – the ram pump: a device so simple that it strains credibility. It’s able to transfer huge quantities of water uphill without any external power source at all – apart from that of the water itself.
Essentially, it works like this: if you have a supply of water flowing downhill (from a spring or a stream, say) you can use the force of its fall to pump some of it uphill, using a simple pump based on the so-called ‘water hammer’ effect.
Ram pumps were very popular in the early 19th century, but fell out of favour with the advent of electric versions, which offered greater flexibility. They continued to be used on isolated farms, and have recently become more popular as a means of bringing water to off-grid communities in developing countries. And as fuel and maintenance costs rise, so the relatively simple ram pumps are beginning to look increasingly economical for the industrialised world, too.
But now a British company, Papa Pumps, is reviving ram pumpswith a different aim in mind: flood control and large-scale water transfer. As Director Hugo Swire explains, “We can put a ram pump inside a national park far from an electricity supply, helping prevent flooding by moving water higher up into the catchment area.”
Papa Pumps’ largest model is able to shift water up to 50km, raising the prospect of it being used for transferring significant quantities between regions with a water surplus and those suffering from drought.
On a smaller scale, Swire even envisages them being used for local urban flood prevention. “You could install small pumps in the drains beneath a supermarket car park, say.” As well as stopping dangerous levels of run-off during heavy rains, the water could be pumped back up for use in car washes, toilet flushing, or to irrigate green roofs, all at zero energy cost.
Not as glamorous as a balloon ride, maybe – but arguably a lot more useful in an increasingly turbulent climate. – Martin Wright
Photo: Martin Wright