Meetings, Agendas and Background Documents

Flood Insurance Information

Read more information about flood insurance.

Land Use Applicatoin For Developers

The District’s Resolution that includes the FCD10 Land Use Change Application is available for download here. For questions, please contact Mike Dimmick, FCD10 Project Manager 208.861.2766

Studies

Impact of Channel Vegetation

A floodplain hydraulic model was developed to simulate the effects of channel vegetation on river water surface elevations and the extent of floodplain inundation along the Eagle Island section of the Boise River. This analysis investigated the impact of channel vegetation on both channel and the adjacent floodplain.

Glenwood Blocage

Here are the results of a computer simulation depicting potential flooding effects of a partial blockage of the Glenwood Bridge, during a flow of 16,600 cfs, the “100-yr Flood Event” on the Boise River.

Effects of Vegetation in Channels

One hundred and fifty years ago the Boise River was an un-managed, natural river. With the introduction of mining activities in the Boise River Basin in the late 1800s, the construction of Arrowrock Dam in 1915, Anderson Ranch Dam in 1950, Lucky Peak Dam in 1957 and the growth of population centers in the Lower Boise River Basin, the Boise River has evolved into a semi-channelized, managed urban river. Prior to these modifications the average bank-full width of the Boise River, just upstream of Eagle Island, was approximately 274 m. Now it is approximately 43 m. Before construction of the dams, the two year recurrence peak flow was approximately 10,700 cfs. Now it is 3,700 cfs. In its current configuration, the Boise River serves a broad range of constituencies including agriculture (through a system of irrigation canals), urban water supply, recreation (fishing, boating, municipal parks), habitat for a broad range animal species (including trout, deer and bald eagle) and provides an esthetically pleasing corridor for the cities of Boise, Eagle, Star and Caldwell. As these communities have grown and closed in upon the river, flood control has become a primary concern for those that live and work along the river as well as those who are responsible for managing the river and its environment.

Eagle Island Ecosystem Resotration Plan

Boise River at Eagle Island Ecosystem Restoration Project Background The Corps and Boise River Flood Control District #10 (FCD10) are partnering on the Boise River at Eagle Island Environmental Restoration Project. The project is being conducted in accordance with Section 1135 of the Water Resources Development Act of 1986, which authorizes the Corps to modify existing Corps projects to restore the environment or construct new projects to restore areas where Corps projects have contributed to degradation of environmental quality.

The Corps is preparing a Feasibility Report (FR) and Environmental Assessment (EA) that will identify and evaluate the effects of alternative plans. The study process and documents will be prepared to satisfy the requirements of the National Environmental Policy Act and other applicable environmental laws and regulations.

The Boise River at Eagle Island Environmental Restoration Project is located approximately 15 miles downstream of Lucky Peak Dam where the lower Boise River splits into north and south channels, creating Eagle Island. The project area is located within the floodplain of the Boise River near the cities of Eagle, Garden City and Boise in Ada County, Idaho. The project is focused from the head of Eagle Island, downstream along both the north and south channels, to approximately the west end of the existing gravel ponds.

The objective of the proposed project is to restore the biological (aquatic and riparian communities) and physical (floodplain functions, sediment transport and channel hydraulics) components at and near the head of Eagle Island to a more naturally functioning and self-sustaining state. This area has been affected by flow regulation, irrigation diversion, flood control projects, gravel mining and land development encroachment from the 1950s to the present day. The project would also accommodate short-term and long-term goals and priorities to improve floodplain functions.

Permits