Today's deltas are impacted negatively by (1) accelerated subsidence (e.g., from ground fluid extraction), (2) global eustatic sea level rise, and (3) decreased sediment supply, which increasingly starves these landforms of sediment necessary to sustain their footprint. This growing vulnerability threatens many megacities that have developed due to the rich resources offered by deltas and therefore urgently calls for efforts to maintain sustainability. The Yellow River of China is classic example of such a landform under threat and which requires human intervention to maintain its resilience. Since 2002, the Yellow River Conservancy Commission has enacted an annual water and sediment regulation scheme (WSRS) by coordinated operation of three large reservoirs in the mainstream. Here we evaluate the efficiency and sustainability of this man‐made experiment on delta evolution. The impulsive delivery of muds and sands, within ~20 day intervals (averaged duration of the WSRS), did indeed move the present Yellow River delta from a destructive phase to an accretion phase. With continuous scouring, however, the downstream riverbed erosion efficiency has decreased, due to coarsening of surface bed material sediment. Concomitantly, sediment delivery has decreased, resulting in the present delta once again entering an erosive (destructive) phase, since 2014. From a perspective of delta restoration, the WSRS on the Yellow River is effective but potentially unsustainable. Restoring delta resilience necessitates an enhanced, coordinated effort, relying upon new sciences advances, rather than simply assuming channel scour will address the sediment deficit of the delta.

The integration of multi-source, multi-temporal, multi-band optical, and radar remote sensing images to accurately detect, extract, and monitor the long-term dynamic change of coastline is critical for a better understanding of how the coastal environment responds to climate change and human activities. In this study, we present a combination method to produce the spatiotemporal changes of the coastline in the Yellow River Delta (YRD) in 1980–2020 with both optical and Synthetic Aperture Radar (SAR) satellite remote sensing images. According to the measurement results of GPS RTK, this method can obtain a high accuracy of shoreline extraction, with an observation error of 71.4% within one pixel of the image. Then, the influence of annual water discharge and sediment load on the changes of the coastline is investigated. The results show that there are two significant accretion areas in the Qing 8 and Qingshuigou course. The relative high correlation illustrates that the sediment discharge has a great contribution to the change of estuary area. Human activities, climate change, and sea level rise that affect waves and storm surges are also important drivers of coastal morphology to be investigated in the future, in addition to the sediment transport.

The quantity and grain size of river‐borne sediment are critical to geomorphological evolution and ecosystem health of river deltas. Compared to quantitative aspects of fluvial systems, however, studies describing the physical properties of river sediment are still quite limited. This work examines how an unprecedented engineering effort (the Water‐Sediment Regulation Scheme, WSRS) within the lower Yellow River system has caused important changes in the volume and grain size patterns of transported sediment. After the implementation of the WSRS, artificial floods dominated the delivery of water and sediment to the delta region—the natural (seasonal) rhythm of the hydrological cycle has been replaced by impulsive delivery. Compared to natural floods, the duration of the artificial flood due to WSRS is substantially shortened, and timing has changed to early summer (June to July), which is two to three months ahead of the usual flood season. Now, as a result of WSRS, there are high sediment loads over a shorter than usual time frame. The Yellow River's sediment load rebounded and coarsened, because artificial floods have strongly scoured the river channel. These changes turned the Yellow River delta from a recession phase to one of progradation, and caused impulsive delivery and rapidly buried of terrestrial organic carbon and pollutants. For other rivers worldwide, the lower Yellow River system provides an illustrative example of how transporting coarse‐grained sediment, otherwise deposited on river bed, may be used to mitigate coastal land loss on intra‐decadal time scales, however with the potential for adverse ecological impacts.