A peer-reviewed study has proposed that ancient Egyptians may have used a water-powered lifting system to build the Step Pyramid of Djoser at Saqqara, the oldest of Egypt’s seven monumental pyramids. The paper, published in PLOS ONE, reinterprets several large-scale features surrounding the pyramid as components of a hydraulic apparatus, an idea that has drawn both attention and skepticism from the broader archaeological community. If the hypothesis holds up under further scrutiny, it would rewrite long-standing assumptions about how the earliest monumental stone structures were raised roughly 4,500 years ago.
A New Reading of Familiar Ruins
For decades, Egyptologists have cataloged the structures around the Step Pyramid without connecting them into a single engineering system. The new study changes that framing. Researchers propose that three distinct features at Saqqara worked together as a hydraulic elevation mechanism never previously reported in the archaeological literature. The three components are the Gisr el-Mudir enclosure, the southern Dry Moat (also called the Deep Trench), and the pyramid’s own internal north shaft.
Each feature, the authors argue, played a specific role. The Gisr el-Mudir, a massive stone enclosure located west of the pyramid complex, is reinterpreted as a check dam or sediment trap designed to capture and control floodwater. The southern Dry Moat, a long trench running along the complex’s perimeter, is cast as a multi-compartment water-treatment sequence that filtered and channeled water toward the pyramid’s core. And the internal north shaft, long studied as a burial or ritual passage, is proposed to have served as a vertical conduit through which pressurized water could float stone blocks upward during construction.
The PLOS ONE article belongs to a broader ecosystem of open-access research that encourages unconventional approaches to long-standing questions. Journals in this family routinely issue themed calls for papers that invite cross-disciplinary work, and the editorial policies, outlined in the editor resources, emphasize methodological transparency over consensus with prevailing theories. That context helps explain how a speculative but carefully argued idea about ancient hydraulics reached publication while still being presented as a hypothesis rather than a settled explanation.
What the Dry Moat Reveals
The Dry Moat has been studied for years by Polish archaeologists working at Saqqara. The Polish Centre of Mediterranean Archaeology at the University of Warsaw maintains a dedicated project page that records the trench’s approximate dimensions and provides a bibliography stretching back to Nabil Swelim’s publications in 1985, 1988, and 2006. Geophysical surveys by Herbich and Jagodziński in 2008 confirmed the trench’s artificial origin, and Karol Myśliwiec published further analysis in 2006.
What the new study adds is a functional reinterpretation. Rather than viewing the Dry Moat as a defensive boundary or quarry remnant, the researchers describe it as a staged water-processing channel. Compartments within the trench, they argue, would have allowed sediment to settle progressively, delivering cleaner water to the pyramid’s internal shaft system. This reading depends on the assumption that Saqqara received significantly more rainfall during the Old Kingdom than it does today, a point supported by paleoclimate data indicating wetter conditions in the Nile Valley about 4,500 years ago.
In this scenario, seasonal floodwaters or heavy rains would have been diverted first into the Gisr el-Mudir, where coarse sediments dropped out. Partially clarified water would then flow into the Dry Moat, passing through successive basins that further reduced suspended material. Only after this multi-stage settling process, the authors suggest, would the remaining water have been suitable for use in a hydraulic lift, minimizing abrasion and clogging inside the pyramid’s internal structures.
How the Internal Shaft Fits
The most striking element of the hypothesis centers on the Step Pyramid’s north shaft. The authors propose that this vertical passage was not purely ceremonial or funerary but was engineered to exploit water pressure. In their model, water channeled from the Dry Moat into the shaft could generate enough upward force to assist in lifting heavy limestone blocks during the pyramid’s construction phases.
This idea directly challenges the conventional explanation that ramps and sledges were the primary tools for raising stone. Ramp theories have dominated Egyptology for over a century, supported by physical evidence at later pyramid sites and by experimental archaeology. The hydraulic hypothesis does not necessarily replace ramps entirely but suggests that, at least at Saqqara, builders may have combined water-based lifting with other techniques. The article’s abstract describes the Step Pyramid as the earliest of the monumental pyramids and frames the proposed system as a previously unreported construction method.
In practical terms, the model imagines stone blocks loaded into a water-filled chamber connected to the shaft. As water levels rose, buoyant force would reduce the effective weight of the blocks, allowing smaller teams to guide them upward or onto higher tiers. The concept draws on basic hydrostatics rather than advanced machinery, but it would still imply a level of planning and hydraulic control not usually attributed to Third Dynasty builders.
Scientific Reception and Open Questions
Coverage in Nature has linked the hydraulic-lift claim to the PLOS ONE paper and described it as a debated and novel interpretation. That framing is telling. A short news-style highlight signals that editors consider the work interesting enough to bring to a wider scientific audience, but the format also carries an implicit caveat: it flags novelty without endorsing conclusions, and it often notes where other specialists see weaknesses.
Several gaps in the evidence deserve attention. No primary excavation report has yet confirmed the presence of water channels or hydraulic infrastructure inside the pyramid’s north shaft. The current evidence rests on geophysical modeling, architectural analysis, and historical analogies rather than direct physical proof of water flow. No official response from Egyptian antiquities authorities has been reported in connection with the hypothesis. And no leading Egyptological institutions outside the study’s own authors have published formal assessments of the claim.
The absence of sediment core samples or hydrological models tied to specific Nile flood records from the Old Kingdom era also limits the hypothesis. The authors rely on general paleoclimate evidence to argue that enough water was available at Saqqara, but site-specific data on water volume and seasonal timing has not been presented. Without that, the mechanical feasibility of the proposed system remains theoretical and difficult to test against the known mass and number of blocks used in the Step Pyramid.
Some of the broader discussion around the study has unfolded in venues that require registration or institutional access. Readers who want to follow expert commentary in more detail may need to create a personal account with the publisher hosting Nature’s content, which controls access to certain discussion tools and saved-article features.
Why Ramp Theory Persists
The dominance of ramp-based explanations is not simply tradition. At Giza and other later pyramid sites, archaeologists have found physical traces of construction ramps, including the remains of a ramp system at Hatnub that dates to roughly the same era. Experimental teams have demonstrated that wooden sledges on wetted sand can move multi-ton blocks with surprisingly modest labor forces. These findings give ramp theory a material basis that the hydraulic hypothesis has not yet matched at Saqqara.
That said, the Step Pyramid is architecturally distinct from later pyramids. Its stepped profile, smaller individual layers, and position at the dawn of large-scale stone construction make it plausible that builders experimented with different methods before the straight-sided pyramids of the Fourth Dynasty. The new study leverages that uniqueness, arguing that a one-size-fits-all explanation for pyramid building may obscure local innovations and short-lived techniques that were later abandoned.
For now, most specialists appear to regard water-powered lifting as an intriguing but unproven possibility. The burden of proof remains high: researchers would need to uncover clear archaeological traces of channels, valves, or wear patterns consistent with sustained water flow, and to show that the proposed system could have operated reliably under the climatic and logistical constraints of the Old Kingdom.
Open Science, Costs, and Communication
The debate also illustrates how open-access publishing shapes public understanding of controversial ideas. Because the PLOS ONE paper is freely available, non-specialists can examine the diagrams, calculations, and references for themselves. At the same time, publishing in such venues involves practical considerations. Prospective authors must navigate article processing charges, which support open access but can be a barrier for researchers without institutional funding, and rely on editorial workflows designed to assess technical soundness rather than consensus.
Once a study appears, its visibility often depends on how effectively journals and authors communicate with journalists and the public. Organizations like PLOS maintain dedicated press and media channels that highlight selected articles and provide context for reporters, which can amplify controversial findings far beyond specialist circles. In parallel, news outlets such as Nature’s newsroom play a gatekeeping role, deciding which papers merit additional attention and framing them for general audiences.
As the hydraulic-lift hypothesis circulates through this ecosystem, its fate will likely hinge less on headlines than on slow, cumulative work at Saqqara itself. Targeted excavations in and around the Dry Moat, detailed hydrological modeling, and renewed study of the Step Pyramid’s interior could either strengthen the case for ancient water-powered engineering or relegate the idea to the long list of imaginative but unsupported pyramid theories. Until then, the proposal stands as a reminder that even the most familiar monuments can yield radically new interpretations when viewed through a different lens.
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*This article was researched with the help of AI, with human editors creating the final content.
