This study presents a systems modeling methodology to determine the quantity of water to supply among wetland units to increase ecological performance. Ecological performance is measured by a parameter defined as weighted usable area for wetlands (WUAW). The WUAW represents the surface area available that provides suitable condition to reach specific wetland management goals and is measured in square meters. The systems model considers water depth, flow duration, and vegetation coverage as decisions variables to improve wetland performance. Input data include water depth/area relationships in individual wetland units, wetland water distribution network of canals and remote sensing images. Hydrological and ecological decisions are limited by water availability, spatial connectivity, and hydraulic infrastructure. These decision variables, performance indicators, and constraints were identified through participatory meetings and discussions with wetland managers at the Bear River Migratory Bird Refuge (BRMBR). The BRMBR is located on the northeast side of Great Salt Lake, Utah and constitutes one of the most important habitats for migratory birds for the Pacific and Central Flyway of North America. The study showcases a methodology to allocate water to improve ecological benefits in wetlands. © 2010 ASCE.