When the electricity failed after 168 millimetres (6.6 inches) of rain fell in 11 hours on 28 September, Jéssica Macedo’s hydraulic ram pump kept feeding an uphill storage tank. The device, which uses the force of flowing water rather than a motor, helped maintain supply to 31 homes through a 14-hour blackout in the hills outside Lousã.
Macedo, 58, built the pump in 2019 from steel pipe, salvaged valves and a small concrete channel. It lifts water 41 metres (135 feet) from a stream to a treatment basin, where it enters the village supply. “People thought I was making an old machine for the pleasure of it,” she said. “Now they want to know why it isn’t on the emergency map.”
The pump that kept running
The storm drove the stream’s flow sharply higher, and the pump delivered about 12,600 litres (3,328 US gallons) to the basin over 18 hours, according to readings recorded by Macedo and checked by researchers. The village’s electric booster stopped during the outage. Macedo’s device did not need the grid, though the treatment system still required staff to monitor water quality.
The result was more than a lucky rescue. A field survey published on Wednesday by the fictional Institute for Catchment Engineering identified 12 functioning hydraulic ram pumps across 24 mountain villages. Their combined tested capacity was 44,000 litres (11,623 US gallons) a day, but none appeared on the emergency maps researchers examined.
Vid Radić, the institute’s lead hydrologist, said teams confirmed each pump on site and compared its location with municipal supply plans. “This is not a museum curiosity,” he said. “It is working infrastructure, but planners cannot send crews to equipment they do not know exists.”
The researchers say the pumps could provide backup supply when storms cut electricity or landslides block roads. They do not replace treatment systems, and their output depends on stream flow and regular maintenance. Radić said the survey was limited to villages in central Portugal, so the national number could be higher.
A missing line on the map
They are working machines, but planners cannot send crews to equipment they do not know exists.
Vid Radić, hydrologist
Macedo’s pump emerged from years of frustration with repeated summer restrictions and winter outages. She applied for €420,000 (about US$493,000) in municipal adaptation funding for a grid-powered booster and storage upgrades; the proposal was not selected in 2024. Her low-cost ram pump was built separately, with no formal role in the town’s emergency plan.
The municipal water office said it would review the researchers’ findings and add verified backup sources to its next emergency-planning update. It did not say when that work would be completed. The office’s current plan lists generator-powered stations and tanker delivery points, but no hydraulic ram pumps.
Macedo now checks the valves each week and has shown two neighbours how to spot a blockage. She wants the village’s pump inspected before the next storm, not praised after it. “We were lucky this time,” she said. “A plan should not depend on somebody remembering that a machine exists.”
