The dataset represents micro computed tomography (µCT) images of undisturbed samples of constructed Technosol, obtained by sampling from the top layer of the biofilter in two bioretention cells. A bioretention cell is a stormwater management system designed to collect and temporarily retain stormwater runoff and treat it by filtering it through a soil media called a biofilter. Soil samples were collected at 7, 12, 18, 23, and 31 months after the establishment of bioretention cells. The constructed Technosol was composed of 50% sand, 30% compost, and 20% topsoil. The bioretention cell 1 (BC1) was designed to collect water from the nearby building roof, and bioretention cell 2 (BC2) was without regular inflow for possible irrigation events. This allowed for the capture of the dynamics of early soil structure development. The dataset comprises a total of 120 three-dimensional µCT images. The 16-bit µCT images obtained by industrial scanner have resolutions of 12 and 20 µm. The characteristics of total porosity, volumetric weight of the dry sample and field capacity were determined in the laboratory for each sample. The generated dataset captures the soil structure development within the biofilter during the initial years of operation of bioretention cells with two distinct water regimes. Originally produced to describe the development of the macropore system during early biofilter evolution, this extensive and high-quality dataset can be reused for further studies on constructed Technosol evolution, focusing on soil structure or hydraulic properties. It is particularly beneficial for research into macropore network development and changes in hydraulic properties in constructed soils. The dataset can support model validation and improve understanding of soil property variability in bioretention systems. It serves as a valuable resource for researchers who lack the means to collect and scan their own samples.
