A 1948 study tested 58 dowsers' ability to detect water. None of them was more reliable than chance.[17] A 1979 review examined many controlled studies of dowsing for water, and found that none of them showed better than chance results.18

In a study in Munich 1987-1988 by Hans-Dieter Betz and other scientists, 500 dowsers were initially tested for their "skill" and the experimenters selected the best 43 among them for further tests. Water was pumped through a pipe on the ground floor of a two-story barn. Before each test the pipe was moved in a direction perpendicular to the water flow. On the upper floor each dowser was asked to determine the position of the pipe. Over two years the dowsers performed 843 such tests. Of the 43 pre-selected and extensively tested candidates at least 37 showed no dowsing ability. The results from the remaining 6 were said to be better than chance, resulting in the experimenters' conclusion that some dowsers "in particular tasks, showed an extraordinarily high rate of success, which can scarcely if at all be explained as due to chance ... a real core of dowser-phenomena can be regarded as empirically proven."[19]

Five years after the Munich study was published, Jim T. Enright, a professor of physiology and a leading skeptic who emphasised correct data analysis procedure, contended that the study's results are merely consistent with statistical fluctuations and not significant. He believed the experiments provided "the most convincing disproof imaginable that dowsers can do what they claim,"[20] stating that the data analysis was "special, unconventional and customized." Replacing it with "more ordinary analyses,"[21] he noted that the best dowser was on average 4 millimeters out of 10 meters closer to a mid-line guess, an advantage of 0.0004%. The study's authors responded, saying "on what grounds could Enright come to entirely different conclusions? Apparently his data analysis was too crude, even illegitimate."[22] The findings of the Munich study were also confirmed in a paper by Dr. S. Ertel,[23] a German psychologist who had previously intervened in the statistical controversy surrounding the "Mars effect", but Enright remained unconvinced.[24]

More recently a study[25] was undertaken in Kassel, Germany under the direction of the Gesellschaft zur Wissenschaftlichen Untersuchung von Parawissenschaften (GWUP) [Society for the Scientific Investigation of the Parasciences]. The three-day test of some 30 dowsers involved plastic pipes through which water flow could be controlled and directed. The pipes were buried 50 centimeters under a level field, the position of each marked on the surface with a colored strip. The dowsers had to tell whether water was running through each pipe. All the dowsers signed a statement agreeing this was a fair test of their abilities and that they expected a 100 percent success rate, however the results were no better than chance.