Yolo Bypass - FloodProtect

Hydraulic Analysis
of Modification to
the Yolo Bypass
December 6, 2013
Objective of Analysis
Evaluate actions to reduce flood stages in the Lower
Sacramento River/Delta North Region for consideration in the
Regional Flood Management Plan
Initial scope was to evaluate:
1. Actions that increase the capacity of the Yolo Bypass
within the existing footprint
Expanded scope added evaluation of:
2. Widening the Sacramento Bypass
3. Setting back the east levee of the Yolo Bypass in the Lower
Elkhorn area
Study Area
and Project
Elements
Initial Scope: Increase
capacity of Yolo Bypass
A,B
A. Remove spoil mound
B. Thin vegetation
C
D
C. Remove Yolo short line
railroad bridge
D. Re-grade County Road 22
E. Add weir into Deep Water Ship
Channel
F. Add flood barrier in Deep
Water Ship Channel
G. Reduce height of levees in
Lower Egbert Tract
F
E
Meixner’s Spoil Mound
Vegetation near Fremont Weir
Yolo Shortline Railroad Bridge
Vegetation near County Road 22
Regrade County Road 22
Yolo Bypass
to Ship
Channel
Overflow
Reduce
Height of
Lower Egbert
Tract Levees
Expanded Scope
Alternative 2:
Sacramento
Bypass Widening
plus Alternative 1
Alternative 3:
I-5 to Bypass
East Yolo Bypass
Levee Setback
plus Alternative 2
Impact at Specific Locations
Location
Sacramento River
at Verona
at I Street bridge
at Freeport bridge
Yolo Bypass
at Interstate 5
at Interstate 80
1 in 100 AEP Change in
Maximum Water Surface
Elevation (feet)
Base to Base to Base to
Alt. 1
Alt. 2
Alt. 3
1 in 200 AEP Change in
Maximum Water Surface
Elevation (feet)
Base to Base to Base to
Alt. 1
Alt. 2
Alt. 3
-0.4
-0.4
-0.3
-0.5
-1.7
-1.4
-0.6
-1.8
-1.4
-0.2
-0.2
-0.1
-0.3
-1.8
-1.4
-0.3
-1.8
-1.4
-0.3
-0.7
-0.2
-0.6
-0.8
-0.6
-0.2
-0.6
-0.2
-0.4
-0.6
-0.4
+2.1
+2.2
+2.2
+3
+3.2
+3.2
-0.5
-0.4
-0.4
-1.1
0.0
0.0
Ship Channel
at Babel Slough
at north end of
Prospect Island
Greatest Reduction in Stage
1 in 100 AEP Change in
Maximum Water Surface
Elevation (feet)
Location
Sacramento River – just
upstream of the
Sacramento Weir
American River – at
mouth near Interstate 5
Yolo Bypass - ¼ mile
upstream of Interstate 5
1 in 200 AEP Change in
Maximum Water Surface
Elevation (feet)
Base to
Alt. 1
Base to
Alt. 2
Base to
Alt. 3
Base to
Alt. 1
Base to
Alt. 2
Base to
Alt. 3
-0.4
-2.0
-2.0
-0.2
-2.1
-2.1
-0.4
-1.8
-1.8
-0.2
-0.2
-1.9
-0.8
-0.8
-1.3
-0.7
-0.7
-1.1
Greatest Increase in Stage
1 in 100 AEP Change in
Maximum Water Surface
Elevation (feet)
Location
Sacramento River – near
Cache Slough
Cache Slough – at Ryer
Island
1 in 200 AEP Change in
Maximum Water Surface
Elevation (feet)
Base to
Alt. 1
Base to
Alt. 2
Base to
Alt. 3
Base to
Alt. 1
Base to
Alt. 2
Base to
Alt. 3
+0.21
+0.22
+0.22
+0.57
+0.58
+0.59
+2.26
+2.31
+2.31
+2.86
+2.91
+2.93
Questions
Stage East of Bypass
1 in 100 AEP Change in
Maximum Water Surface
Elevation (feet)
Location
Cache Slough – below
Haas Slough
Lindsey Slough – at
Hastings Island Bridge
1 in 200 AEP Change in
Maximum Water Surface
Elevation (feet)
Base to
Alt. 1
Base to
Alt. 2
Base to
Alt. 3
Base to
Alt. 1
Base to
Alt. 2
Base to
Alt. 3
-1.2
-1.2
-1.2
-0.6
-0.5
-0.5
-1.2
-1.1
-1.1
-0.6
-0.5
-0.5
Sacramento River
Sacramento River
Yolo Bypass
Yolo Bypass
-0.8
-1
15
20
25
30
35
River Mile
40
45
-0.6
50
Fremont Weir
Ridge Cut
0.2
Woodland Gage / RR Bridge
Cache Cr Settling Basin Weir u/s
Interstate 5
Road 25 at W Levee
Sac Bypass
Interstate 80
SPRR Bridge
Putah Cr
Road 36
Lisbon Gage
Hackman Rd./Road 38A
Thomsen Rd.
Midway Rd/Road 152
King Rd.
Road 155
Delhi Rd.
Liberty Is (north end)
Liberty Is (south end)
Lindsay Sl
Effect (feet)
Effect of Selected Upper Yolo Bypass Footprint
Components on Yolo Bypass Maximum Water
Surface Elevation
0.4
200-yr Alt 1
100-yr Alt 1
0
-0.2
-0.4
55
-0.4
45
50
55
60
65
River Mile
70
75
80
u/s Fremont Weir
Feather River
Verona gage
Natomas Cross Canal
Interstate 5
Interstate 80
u/s Sacramento Weir
I Street Bridge
American River
Pioneer Memorial Bridge
Freeport gage
Effect (feet)
Effect of Selected Upper Yolo Bypass Footprint
Components on Sacramento River Maximum Water
Surface Elevation
0
200-yr
100-yr
-0.1
-0.2
-0.3
-0.5
85
-2
45
50
55
60
65
River Mile
-2.5
70
75
80
u/s Fremont Weir
Feather River
Verona gage
Natomas Cross Canal
Interstate 5
u/s Sacramento Weir
Interstate 80
I Street Bridge
American River
Pioneer Memorial Bridge
Freeport gage
Effect (feet)
Combined Effect on Sacramento River
Water Surface Elevation
0
200-yr
100-yr
-0.5
-1
-1.5
85