NATOMAS LEVEE PROJECT

Natomas Levee Project—U.S. Army Corps of Engineers 

Goal:  Complete levee improvements started by SAFCA/State to provide Natomas Basin at least 200-year flood protection

Project Status:  Project is fully authorized by Congress (2014 Water Resources and Reform Development Act).  Appropriations are made on an annual basis

Cost Sharing Partners:  SAFCA (local) and Central Valley Flood Protection Board (State)

Operation and Maintenance Responsibility:  Reclamation District No. 1000

Construction Status:  See Construction Phasing Map

February 2021 Status:

Reach A

   i.      The Corps will issue its 100% plans for this reach in mid-February. These 100% plans will purportedly address utility relocations and modifications to Pumping Plants 1A and 1B and some grading details which have not yet been available. A one-week review period for local agencies has been requested by the Corps. 

   ii.      SAFCA continues acquiring necessary right of way including 5 homes upstream of I-80 and 7 homes downstream; relocation assistance is being provided to existing residents of the acquired homes.  An easement from the State Lands Commission may need to be acquired for Pumping Plant 1B outfall work.

   iii.      Removal of trees on the existing levee is proceeding.  Contract award is scheduled for September 2021 with cutoff wall and adjacent levee construction starting in spring 2022. Removal of trees in the newly acquired Right of Way will commence in December 2021.

Reach B

   i.      Relocation of the Riverside Canal is progressing from the north end of the project to Farm Road with the fusing of the HDPE pipe, backfilling of the pipe, and construction of the terminal and turnout structures. 

   ii.      Construction of the adjacent levee has commenced on a limited scale as the availability of 3:1 slope levee borrow material allows. The pace of levee construction is expected to accelerate in the spring once identified borrow sites become more available. 

   iii.      Relocation of overhead power and communication facilities is progressing at a steady rate.

   iv.      Design of the project to close the I-5 window crossing the Sacramento River in Reach B is complete but the bid process has been suspended pending negotiations between Caltrans and DWR/SAFCA on a framework agreement for all NLIP projects impacting Caltrans facilities.    This agreement is expected the first quarter of 2021.

   v.      The project schedule has slipped slightly due to delays in certifying a revised Environmental Document and delays in securing a CalTrans permit.

Reach C

   i.      The Reach C project was completed by SAFCA several years ago and the District’s role is now providing annual maintenance activities in this reach.

Reach D

   i.      The contract for reconstruction of Pumping Plant 4 has been bid and contract award is scheduled in late February.  Construction is scheduled for spring 2021. The Corps has requested the District’s assistance to prevent swallows nesting in the sump area—working with SAFCA,

   ii.      Relocation of the Vestal Drain and most levee work on Reach D was completed last spring.  The District continues to work with SAFCA, DWR and the Corps to resolve some minor clean up and repair issues.

Reach E

   i.      The revised 65% plans have been completed.  The 95% plans are due the end of April which is a hard deadline.   Project advertisement in September 2021 with award by January 2022 (construction 2022 and 2023).

   ii.      SAFCA and State DWR continue working on right of way acquisition and coordination with Sutter County on the Howsley Road bridge replacement project at the northern end of Reach E and several other critical design issues for inclusion by the 100% design in June 2021.

Reach F and Reach G

   i.      Reaches F and G are being designed concurrently as a single project along the Natomas East Main Drain Canal from Sankey Road to Elkhorn Blvd. 

   ii.      The 35% plans will be ready for our review in early February with 65% plans due in June.   RD 1000 is coordinating with SAFCA, DWR and the Corps on a final design water surface profile as well as channel improvements south of Sankey Road to address potential overtopping during the 200-year flood.

   iii.      Current plans propose levee widening and potentially limited cutoff walls.  Current schedule is for Contract Award in spring 2022.

Reach H

   i.       Levee cutoff walls, slope flattening and levee restoration work has been completed for 2020 and the project has been winterized. Patrol / maintenance road grading, fence relocations, and restoration of East Levee Road will recommence in spring 2021.

   ii.      The reduction in pumping capacity due to the damaged discharge pipes 6 & 7 at Pumping Plant 8 has been determined by hydraulic modeling to be slight, in comparison to the loss of pumping capacity caused by raising the pipes over the levee.  A joint project with SAFCA to restore Pumping Plant capacity to pre-Reach H project levels has been planned for implementation upon the completion of the Reach H Corps project.

Reach I

   i.      Construction of the cutoff wall has been completed and project finalization and turnover to SAFCA and the District is in progress. 

   ii     The separate contract (Reach I Contract 2) to construct a patrol / maintenance road and perform levee slope flattening has been delayed due to right of way acquisition issues.    Construction is scheduled for 2023 or later.