China's oldest ceramic drainage system found — 4000 years old

Pingliangtai endured a temperate monsoonal climate with notable temperature and rainfall changes. During the summer, the site witnesses heavy rainfall, sometimes exceeding 500 millimeters (mm) per month.

Situated on a floodplain, the Pingliangtai settlement enjoyed convenient water access but also encountered climate-related uncertainties.

Prior studies across Asia hinted at links between water infrastructure growth and social hierarchy. Nonetheless, the varied paths of water management evolution, potentially beyond hierarchical systems, remain insufficiently explored.

In tackling this issue, Hai Zhang, Yijie Zhuang, and their team meticulously examined 147 sediment cores extracted from the Huaiyang region, home to Pingliangtai.

Their investigation uncovered signs of short-term precipitation fluctuations around 4200 BP (before present), encompassing notably intense rainfall episodes.

Furthermore, the researchers carried out an extensive excavation at the Pingliangtai site, delving into how its 460–600 inhabitants coped with flooding.

Their findings suggest a well-thought-out response. The community at Pingliangtai, it appears, established and maintained a two-tiered drainage system.

They discovered ceramic drainage pipes, dated to around 4100–3900 BP, alongside a network of drainage ditches adjacent to houses. These ditches led to a communal drainage area and displayed signs of multiple rounds of repair and reconstruction.

Interestingly, while household-centered ditches would have likely been constructed and maintained locally, the presence of ceramic drainage pipes and public space ditches indicated a higher degree of planning and coordination. 

It's worth noting that Pingliangtai wasn't characterized by a socially hierarchical structure. Hence, the authors posit that the management of this infrastructure reflects collaborative water governance.

Ultimately, the study sheds light on the dynamic approach to water management undertaken by Pingliangtai's inhabitants, revealing a cooperative and thoughtful strategy to handle the challenges their flood-prone location posed.

The complete study was published in Nature Water on August 14 and can be found here. 

Study abstract:

The earliest ceramic drainage system unearthed at the Pingliangtai site on the Central Plains of China represents an unprecedented social and environmental manipulation as societies faced surging environmental crises in the Late Holocene East Asian Monsoon region. Here we present results of excavation and a geoarchaeological survey of the water-management infrastructures and environment which reveal the operation and maintenance of a well-planned and regulated two-tiered drainage system. Rather than a 'centralized hierarchy', the drainage activities were mainly practised at household and communal levels, through which Pingliangtai society was drawn to more pragmatic aspects of social governance. Through their emphasis on spatial uniformity, cooperation in public affairs, and a series of technological innovations, water management at Pingliangtai gravitated to collective shared interest as the society responded to recurrent environmental contingencies. Such a pragmatic focus on public affairs constituted a previously unrecognized, alternative pathway to the development of power structure and social governance on the Central Plains regimes in late Neolithic and later times.