"Challenges in Development of Water Monitoring Plans for the National Park Service: Examples from the Northern Plains Inventory and Monitoring Network" The National Park Service is currently engaged in an inventory and monitoring program to facilitate long-term management of park resources. The objectives of our effort were to (1) define existing water quality, habitat and biotic data that would support an I&M effort within the Northern Glaciated Plains Network (NGPN), (2) establish baseline conditions against which future monitoring of water quality, habitat and biota might occur and (3) develop a draft water quality monitoring plan for the NGPN. Focus sessions with park staff and historical data have identified water quality concerns, providing the basis for the current water quality plan. The current version focuses monitoring efforts mostly on medium stream and large river drainages. Assigned beneficial uses, water quality standards and 303d listing all contribute to parameter selection for individual streams and rivers. While the final statistical design of the monitoring network is still under discussion, it will be probability-based. The network will likely need to partner heavily with other state and federal agencies to stretch limited resources and will likely use established U.S. EPA EMAP protocols. Those drainages already intensively monitored by other agencies would receive less attention, allowing the NPS to focus efforts to fill data gaps in other monitoring programs. A delicate balance must be reached between the monitoring needs of the network, individual parks and partnering agencies. Sustainable implementation of this effort will require continued communication and commitment from these partners. Nels Troelstrup, South Dakota State University