Movement through streams is critical for the maintenance of diadromous fish populations. Numerous fish passage improvement techniques exist and managers require knowledge of their effectiveness to conserve diadromous species. The passage success of young-of-year (YOY) Galaxias sp. through a pipe-culvert was monitored using a mark-recapture technique, before and following the creation of a pool within the culvert, to investigate whether fish passage improved compared to a control site. A lateral ridge rock-ramp fishway was installed downstream of the culvert to decrease water velocity within the culvert and baffles were installed in the upstream portion of the culvert to provide refuge from higher water velocity at this location. The passage success of YOY Galaxias sp. increased following these treatments to similar levels observed at a control site. Field evaluation and demonstration of the effectiveness of the fishway and baffles on a 70 m culvert provides managers with an important case-study to further adopt this technique to improve fish passage on a broader scale and fills a knowledge gap in the primary literature relating to the success of this technique.