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Human burial in cemeteries facilitates the decomposition of corpses without posing a public health danger. However, the role of cemeteries as potential environmental reservoirs of drug-resistant pathogens has not been studied. Thus, we investigated cemeteries as potential environmental reservoirs of multi-drug resistant (MDR) pathogenic Escherichia coli. E. coli isolates were obtained from water samples (collected from surface water bodies and boreholes in three cemeteries) after isolation using the Colilert® 18 system. Pathogenic potentials of the isolates were investigated using real-time polymerase chain reactions targeting seven virulence genes (VGs) pertaining to six E. coli pathotypes. The resistance of isolates to eight antibiotics was tested using the Kirby–Bauer disc diffusion method. The mean E. coli concentrations varied from <1 most probable number (MPN)/100 mL to 2419.6 MPN/100 mL with 48% of 100 isolates being positive for at least one of the VGs tested. Furthermore, 87% of the isolates were resistant to at least one of the antibiotics tested, while 72% of the isolates displayed multi-drug resistance. Half of the MDR isolates harboured a VG. These results suggest that cemeteries are potential reservoirs of MDR pathogenic E. coli, originating from surrounding informal settlements, which could contaminate groundwater if the cemeteries are in areas with shallow aquifers.

Highlights• The role of the fractured intermediate vadose zone is becoming increasingly important.• Discontinuity geometry affects flow, most notably due to changes in aperture, roughness and infill.• The applicability of the cubic law is often queried.• Better understanding will contribute to issues of slope and excavation stability and contaminant transport.• Open questions requiring addressing concluded the paper. Abstract:Fracture flow is fairly well documented with the widespread application of, for instance, the cubic law and assumed smooth parallel plate model.Geometrical intricacies such as aperture, roughness and infill do however significantly influence the validity of the cubic law with even its application to smooth parallel systems being contestable. Rock mechanical discontinuity surveys provide valuable information regarding the discontinuity geometry that can likely contribute to the evaluation of flow through individual fractures with variable properties. The hydraulic aperture is available for the transmission of flow, while normal and shear stresses alter discontinuity properties over time. In this, numerous advances have been made to better accommodate deviations of natural discontinuity geometry to that of smooth parallel plates and at partial saturation. The paper addresses these advances and details conditions under which the cubic law, even in local form, fails to adequately estimate the

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