In recent decades, watershed managers have increasingly turned to collaborative models of governance for water resource planning in the Western United States. By involving a wide array of stakeholders in decision-making, these place-based partnerships promise many benefits: better understanding of local needs, increased public support, and reduced conflict. Yet, many basins involve powerful, non-local stakeholders, who may not participate in place-based partnerships but can still hinder the collaborative process and derail implementation. One such case is the Icicle Creek Subbasin of Washington State, where a local partnership has been involved in comprehensive watershed planning since 2012. In order to mitigate the impact of droughts and boost instream flow, the Icicle Work Group’s plans have included infrastructural upgrades to storage dams in a federal wilderness area. These projects have drawn intense criticism and threats of litigation from conservation and recreational organizations, who see their wilderness interests threatened by the projects. This research examines the Icicle Creek case study and asks the following research question: How did the Icicle Work Group incorporate input from external stakeholders into their collaborative planning process? Did their process address external concerns in ways that mitigate the chance of future conflict? This study uses the well-documented environmental review process to identify the key concerns of external stakeholders and examine how effectively the collaborative partnership was able to address those concerns. Comment letters from external stakeholder organizations were analyzed using reflexive thematic analysis and the agency responses were identified for each theme. Ultimately, the analysis found that the key concerns of outside stakeholders remained throughout the process, as the agencies and work group were unwilling to make major modifications to their plan. This suggests a number of conclusions: 1) place-based partnerships favor maintaining internal consensus over avoiding conflicts with outside groups; 2) the environmental review process is a limited platform for outside stakeholders to shape planning efforts; 3) state agencies involved in the collaborative planning should consider should delegating the environmental review process to an outside agency to avoid perceptions of a conflict of interest; and 4) watersheds with federal wilderness may not be well-suited for local collaboration.