  Regional frequency analysis is an important tool to properly estimate
hydrological characteristics at ungauged or partially gauged sites in order to
prevent hydrological disasters. The delineation of homogeneous groups of sites
is an important first step in order to transfer information and obtain accurate
quantile estimates at the target site. The Hosking-Wallis homogeneity test is
usually used to test the homogeneity of the selected sites. Despite its
usefulness and good power, it presents some drawbacks including the subjective
choice of a parametric distribution for the data and a poorly justified
rejection threshold. The present paper addresses these drawbacks by integrating
nonparametric procedures in the L-moment homogeneity test. To assess the
rejection threshold, three resampling methods (permutation, bootstrap and
P\'olya resampling) are considered. Results indicate that permutation and
bootstrap methods perform better than the parametric Hosking-Wallis test in
terms of power as well as in time and procedure simplicity. A real-world case
study shows that the nonparametric tests agree with the HW test concerning the
homogeneity of the volume and the bivariate case while they disagree for the
peak case, but that the assumptions of the HW test are not well respected.
