The authors regret that there was as error in Figure 9 in their original paper and apologise for any inconvenience caused. Labels for Type 2 and 3 were exchanged by mistake. The correct version of Figure 9 can be found below:

Figure 9

Annus et al. (2020). Dependence between the velocity correction coefficient and the relative roughness (for all pipe types, D = 100 mm and D = 200 mm).

Figure 9

Annus et al. (2020). Dependence between the velocity correction coefficient and the relative roughness (for all pipe types, D = 100 mm and D = 200 mm).