Two independent multirate flow experiments were conducted in 1994 in the open hole depth interval of a well bore at the hot dry rock (HDR) test site Soultz. The steady state and transient downhole pressure records gave clear indications of non-Darcian flow. A numerical model has been set up to evaluate these two measurements. An excellent fit of the transient pressure responses of the two flow tests could be achieved by assuming one model of simple geometry. The model predicts fluid transport along a conduit with substantial surface area in which fully turbulent flow is occurring. All the parameters required by our best-fit simulation fall into a physically reasonable range. Sensitivity analysis demonstrates a non-Darcian flow regime along highly conductive features. The existence of high capacity far-field faults as postulated in our model confirms earlier characterizations of the Soultz test site.¿ 1997 American Geophysical Union