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Zinc concentrations before and after the implementation of remediation strategies were examined in three sub-watersheds in southwestern Colorado. Three tributaries to the Animas River (Cement Creek, Mineral Creek, and the Upper Animas River) were analyzed for pre- and post- remediation changes in zinc loading. A fourth site below all tributaries was also included in this study to observe net effects of remediation strategies on zinc removal. Remediation techniques in Cement creek include water treatment (1989-2003) and installation of multiple bulkheads (1996-2003). Extensive surface remediation took place in Mineral Creek and Upper Animas River on similar timelines, and a single bulkhead was implemented in the headwaters of Mineral Creek. Using regression techniques, daily loads were estimated at each of the sites and analyzed using a Mann Kendall Trend test for time-dependent changes in zinc load. Zinc loads increased following bulkhead installation and cessation of treatment in Cement Creek with the largest increases occurring during baseflow months. Zinc loads in Mineral Creek and Upper Animas River decreased following surface remediation during all periods of the hydrograph. Interestingly, the combined downstream impacts yield small net changes with zinc load increases during low flow and decreases during high flow. Given the scale of the watershed and the interannual variability of flow, longer timescale studies may be more effective in determining efficacy of remediation.