Relative to what National Weather Service gauge location: Missouri River at Nebraska City and Nishnabotna River at Hamburg.
Background: Levee was overtopped/breached on or before 19 Mar 2019. there are 7 breaches identified in the L575 levee system.
Initial closure at breach L575_A_I to return river to the channel. L575_A_I contract awarded 14 Apr 2019, expected completion 03 Jul 2019. Initial closure at breach L575_B_I to return river to the channel. L575_B_I contract awarded 19 Apr 2019, expected completion 08 Jul 2019.
Anticipated construction start: Work started at both locations on 4 May 2019.
Cost: L575_A_I $7.5 million; L575_B_I $12 million
Contractor: L575_A_I - Western Contracting Corp., Sioux City, Iowa; L575_B_I - Newt Maritime Services, Dubuque, Iowa
Risk to normal Spring Runoff operations? Yes
Risk to elevated Spring Runoff operations? Yes
1. Provide an interim level of flood risk reduction at both breach locations.
2. When river returns to channel and levees are accessible, conduct physical damage assessment.
3. Design and construct levee restoration to authorized level of flood risk reduction.