Department of Water Resources Home
Cliff Feldheim, Chief
Environmental Planning and Information Branch
Suisun Marsh Program
3500 Industrial Blvd.
West Sacramento, CA 95691
(916) 376-9693
Email:cliff.feldheim@water.ca.gov
Mailing Address:
P.O. Box 942836
Sacramento, CA 94236-0001
Suisun Banner

Sherman Lake, Franks Tract, & Big Break

Preliminary Alternatives Study
April 2000

Report (including Results)

Results – Spatial Salinity Plots

  1. Breach on Sacramento River Side – Sherman Lake closed with one 100 ft breach located on the Sacramento River side of Sherman Lake.
  2. Breach on San Joaquin River Side – Sherman Lake closed with one 100 ft breach located on the San Joaquin River side of Sherman Lake.
  3. Broad Slough – Sherman Lake closed with one 100 ft breach located on the Broad Slough side of Sherman Lake.
  4. Three Narrow Breaches – Three 100 ft breaches located along the Sacramento River side, Broad Slough, and Mayberry Slough upstream of Mayberry Cut.

    Sherman Lake No Breach Scenario:

  5. Closing Sherman Lake – Reclaiming Sherman Lake.

    East Sherman Lake Channel Scenarios:

  6. East Sherman Lake Channel – Channel along the east side of Sherman Lake from the Sacramento River to Mayberry Cut. The channel is not connected to the Lake. Channel width of 292 ft.
  7. Narrow East Sherman Lake Channel – Channel configuration as described above with channel width decreased to 146 ft.
  8. Wide East Sherman Lake Channel – Channel configuration as described above with channel width increased to 584 ft.
  9. "Ultra-Wide" East Sherman Lake Channel – Channel configuration as described above with channel width increased to 1000 ft.
  10. "Ultra-Wide and Long" East Sherman Lake Channel – Channel configuration as described above and included widening Mayberry Cut to 1000 ft.

    Three Mile Slough Scenarios:

  11. Three Mile Slough – The width of Three Mile Slough was increased to 1000 ft with no change to the existing configuration of Sherman Lake.
  12. Widening Three Mile Slough and Closing Sherman Lake – Combination of 11 and 5 above.
  13. Widening Three Mile Slough and Creating 1000' E. Sherman Lake Channel – Combination of 11 and 9 above.

    Franks Tract Scenarios:

  14. Franks Tract – Reclaim Frank's Tract.
  15. Franks Tract Narrow Breach (East side only, modeled as reservoir) – Simulated 2000 sq. ft. breach on east side of Franks Tract near Mandeville Island. Franks Tract modeled as a reservoir.
  16. Franks Tract 100 sq. ft. Breach (East side only, modeled as reservoir) – Simulated 100 sq. ft. reservoir opening on east side of Franks Tract near Mandeville Island.
  17. Franks Tract Narrow Breach (East side only, modeled as channel) – Simulated 100 ft breach on east side of Franks Tract near Mandeville Island. Franks Tract modeled as wide, shallow channel of width = 3116 ft and length = 6500 ft.
  18. Franks Tract Double Breach (East and West sides) – Simulated two 2000 sq. ft. breaches on east side as described above, and on west side near Bethel Island. Franks Tract modeled as a reservoir.
  1. Franks Tract Narrow Breach (West side only, modeled as channel) (Additional run made in response to review comments, June 7, 2000) – Simulated 100 ft breach on west side of Franks Tract near Bethel Island. Franks Tract modeled as wide, shallow channel of width = 3116 ft and length = 6500 ft.
  2. Franks Tract Narrow Breach Full Area (East side only, modeled as channel) (Added June 13, 2001) – Simulated 100 ft breach on east side of Franks Tract near Mandeville Island. Franks Tract modeled as wide, shallow channel of width = 8340 ft and length = 17,000 ft.

    Big Break Scenarios:

  1. Reclaiming Big Break – Remove Big Break channels.
  2. Big Break Narrow Breach – One 100 ft breach at midpoint of historic channel on north side of Big Break.

    Franks Tract & Big Break Combinations:

  3. Closing Franks Tract and Big Break – Combination of runs 14 and 19 above.
  4. Franks Tract Double Breach and Big Break Narrow Breach – Combination of runs 18 (Franks Tract breached at two locations with 2000 sq. ft. openings) and 20 (Big Break simulated with a narrow, 100 ft wide breach) above.
  5. Franks Tract 100 sq. ft. Breaches and Big Break Narrow Breach – Reservoir openings on node 232 and 219 set to 100 sq. ft. opening size. All other Franks Tract reservoir openings closed as in run 14. Big Break narrow breach (100 ft wide) as described in run 20.

Results – Tidal Range Plots

  1. 28-Day Average Tidal Range, San Joaquin River Breach to Sherman Lake
  2. 28-Day Average Tidal Range, Big Break and Franks Tract Reclamation