Flood Control: The base of the annual flood control and multi-use zone will remain at 57.1 million acre feet (MAF) This is the target storage for the reservoir system on March 1 each year.

Navigation Support Triggers: These are the storage levels that trigger releases for navigation service flows and season length. Lower levels trigger reduced releases for navigation earlier in droughts. During a drought, navigation target flows will be reduced by 3,000 cubic feet per second (cfs) if total system storage is less than 54.5 MAF on March 15. Target flows will be reduced by 3,000 cfs and the season shortened to 7.1 months if storage is less than 59 MAF on July 1. In a severe drought, target flows will be reduced by 6,000 cfs from July 1 to August 20 of the following year. A severe drought is defined as a year in which there is no gain in total storage between March 15 and July 1.

Minimum Storage: This establishes the minimum total storage in the reservoirs during droughts. The new minimum will be 43 MAF in a drought like the 1980s. The low point during that event was 40.9 MAF in January 1989.

Navigation Preclude: This is the minimum storage level on March 15 for navigation support that year. If total storage is less than 31 MAF, there will be no releases from the reservoirs to support navigation.

Flow Enhancement at Fort Peck: This will be an increase in cold water flows from the powerhouse in May and June and a warm water release from the spillway from May through August. These flows are expected to benefit warm water river fish such as the endangered pallid sturgeon.

Flow Enhancement at Gavins Point: The current schedule of flat releases will be maintained to benefit nesting interior least terns and piping plover, two protected shorebird species.

Split Navigation Season: The preferred alternative does not include a split navigation season.

Intrasystem Unbalancing: This is a 3-year cycle of rotating variable water storage in the three largest reservoirs. This will encourage growth of vegetation around the shorelines to provide fish spawning habitat and hiding places for young fish. Lake levels will drop 3 to 5 feet and not affect access.