Levee Decision Analysis Model
Guide to This Workbook
1. LDAM_Island Inputs 4. List of Islands Repaired
This worksheet presents the data inputs for the decision analysis on levee
repairs and upgrades when both land and assets are included. The worksheet
contains the values we used, drawing on source data presented elsewhere in
this workbook. You can change numbers such as property value and
probability of failure to see how the overall decisions would change for each
island. (Results are presented in the next worksheet - "LDAM_Expected
Values").
2. LDAM_Expected Values 5. Source Data (SD) Guide
This worksheet contains the formulas used to generate the expected present
costs for repair and upgrade decisions (using the inputs provided in the
"LDAM_Island Inputs" worksheet). The repair/no repair decision is calculated
under three upgrade scenarios (no upgrade, PL84-99 upgrades, and PL 84-99 +
1 ft SLR upgrades). The upgrade decision is calculated by selecting the lowest
cost scenario, based on present costs. Negative values for present costs
indicate that the scenario is profitable. These formulas are locked and cannot
be manipulated. An explanation of the formulas can be found in Appendix B.
3. LDAM_Repair_Cost_Spread
This worksheet compares the difference in cost between a decision to repair
and a decision to not repair levees after failure under the "no upgrades" and
"PL 84-99 upgrades" scenarios. If the difference between the two decisions is
less than $50,000, the island is assigned to the "unsure" category in terms of
whether it is cost-effective to invest in repairs.
. List of Islands Repaired
This worksheet lists the repair decisions generated by our analysis, using land
values and land plus other asset values, as presented in Appendix B.
IMPORTANT: Because this is NOT a formula-generated list, the results shown
here will not change if the user modifies the values in the "LDAM_Island
Inputs" worksheet.
. Source Data (SD) Guide
This worksheet serves as a guide to the remaining sheets of source data,
which provide information about how our original inputs were calculated.
The numbers and formulas are locked, and cannot be manipulated.
PL 84-99 Upgrade
Island r Property Value Bk Cost
Bacon Island 0.05 $60,164,424 $3,008,221 $40,091,184
Bouldin Island 0.05 $38,937,542 $1,946,877 $50,319,696
Empire Tract 0.05 $18,904,605 $945,230 $29,376,592
Mandeville Island 0.05 $16,943,203 $847,160 $40,009,592
McDonald Tract 0.05 $56,837,848 $2,841,892 $38,356,920
Medford Island 0.05 $10,780,145 $539,007 $16,439,920
Quimby Island 0.05 $2,191,687 $109,584 $19,625,480
Rindge Tract 0.05 $38,422,394 $1,921,120 $44,111,760
Venice Island 0.05 $20,147,964 $1,007,398 $34,754,720
King Island 0.05 $56,130,613 $2,806,531 $25,312,616
Terminous Tract 0.05 $144,375,498 $7,218,775 $61,445,720
Wright-Elmwood Tract 0.05 $42,595,120 $2,129,756 $24,479,336
Brack Tract 0.05 $37,226,096 $1,861,305 $31,945,872
Canal Ranch Tract 0.05 $48,449,544 $2,422,477 $29,176,952
Dead Horse Island 0.05 $1,860,581 $93,029 $7,173,152
Grand Island 0.05 $318,651,235 $15,932,562 $4,610,312
Ryer Island* 0.05 $100,164,068 $5,008,203 $0
Staten Island 0.05 $47,005,675 $2,350,284 $97,665,624
Tyler Island 0.05 $126,068,759 $6,303,438 $36,300,768
Coney Island 0.05 $24,359,255 $1,217,963 $15,354,920
Jones Tract 0.05 $550,468,164 $27,523,408 $52,161,592
Orwood Tract 0.05 $260,065,034 $13,003,252 $23,623,488
Palm Tract 0.05 $27,908,593 $1,395,430 $28,085,008
Roberts Island 0.05 $228,549,230 $11,427,462 $124,031,544
Union Island 0.05 $237,435,567 $11,871,778 $91,087,584
Victoria Island 0.05 $79,696,787 $3,984,839 $42,181,328
Woodward Island 0.05 $129,308,580 $6,465,429 $24,961,944
Bradford Island 0.05 $27,148,842 $1,357,442 $20,717,424
Brannan-Andrus Island 0.05 $289,785,177 $14,489,259 $86,607,528
Holland Tract 0.05 $24,610,343 $1,230,517 $30,591,792
Jersey Island 0.05 $31,886,961 $1,594,348 $43,084,048
Sherman Island 0.05 $141,963,167 $7,098,158 $54,435,752
Twitchell Island 0.05 $23,516,367 $1,175,818 $26,517,456
Webb Tract 0.05 $11,970,466 $598,523 $36,134,840
* Ryer Island has already been upgraded to PL 84-99 standards
PL 84 99
Materials Cost to PL 84-99 + 1 ft SLR Cost of No Annual PL-84-99 + 1' 2000
Raise the Levee 1' Upgrade Cost Repair Cost Repair Pf 2000 Pf Pf
$7,585,353 $47,676,537 $59,648,813 $4,930,479 0.06 0.06 0.05
$9,520,615 $59,840,311 $42,693,179 $213,036,975 0.09 0.08 0.08
$3,970,089 $33,346,681 $30,528,852 $2,580,558 0.06 0.06 0.05
$7,569,915 $47,579,507 $29,628,438 $4,920,445 0.07 0.06 0.06
$7,257,226 $45,614,146 $49,238,517 $4,717,197 0.05 0.05 0.05
$3,110,474 $19,550,394 $29,956,111 $2,021,808 0.05 0.05 0.04
$3,713,190 $23,338,670 $25,471,488 $2,413,574 0.07 0.06 0.06
$8,346,056 $52,457,816 $34,294,391 $5,424,936 0.03 0.03 0.03
$6,575,680 $41,330,400 $30,294,853 $4,274,192 0.11 0.10 0.09
$4,789,210 $30,101,826 $62,863,739 $3,112,987 0.02 0.02 0.02
$11,625,684 $73,071,404 $91,602,821 $76,856,695 0.05 0.05 0.04
$4,631,552 $29,110,888 $27,610,154 $3,010,509 0.02 0.02 0.02
$6,044,239 $37,990,111 $29,089,290 $290,128,755 0.05 0.05 0.04
$5,520,353 $34,697,305 $36,261,928 $100,338,229 0.06 0.06 0.05
$1,357,178 $8,530,330 $25,330,588 $882,166 0.04 0.04 0.03
$15,705,759 $20,316,071 $224,957,140 $632,108,744 0.07 0.07 0.07
$10,715,534 $10,715,534 $57,676,859 $138,815,097 0.05 0.05 0.04
$18,478,581 $116,144,205 $33,147,025 $12,011,078 0.07 0.06 0.06
$13,331,354 $49,632,122 $55,636,559 $8,665,380 0.09 0.08 0.08
$2,905,189 $18,260,109 $46,938,233 $1,888,373 0.04 0.04 0.04
$9,869,104 $62,030,696 $110,767,615 $246,264,918 0.08 0.07 0.07
$4,469,623 $28,093,111 $80,922,337 $2,905,255 0.04 0.04 0.04
$5,313,754 $33,398,762 $32,890,606 $124,503,940 0.08 0.07 0.07
$26,433,775 $150,465,319 $41,504,940 $604,431,954 0.06 0.06 0.05
$17,816,743 $108,904,327 $80,642,709 $11,580,883 0.04 0.04 0.04
$7,980,813 $50,162,141 $65,238,632 $204,987,529 0.06 0.06 0.05
$4,722,862 $29,684,806 $36,907,972 $70,569,861 0.04 0.04 0.04
$3,919,789 $24,637,213 $37,013,466 $2,547,863 0.09 0.08 0.08
$21,472,125 $108,079,653 $170,670,237 $534,606,881 0.08 0.08 0.07
$5,788,044 $36,379,836 $33,729,123 $3,762,228 0.08 0.07 0.07
$8,151,610 $51,235,658 $29,136,997 $5,298,546 0.10 0.09 0.09
$10,299,381 $64,735,133 $52,381,659 $297,394,598 0.07 0.07 0.07
$6,288,610 $32,806,066 $35,294,860 $4,087,597 0.08 0.08 0.07
$6,836,802 $42,971,642 $28,359,022 $4,443,922 0.10 0.09 0.09
Repair Decision with No Upgrades Repair Decision with PL 84-99 Upgrades
Repair?
Island Cost of Repair Cost of No Repair (y/n) Cost of Repair
Bacon Island $76,678,539 $4,930,479 no $111,857,412
Bouldin Island $84,447,573 $213,036,975 yes $129,571,166
Empire Tract $49,834,790 $2,580,558 no $76,743,814
Mandeville Island $55,466,818 $4,920,445 no $93,111,504
McDonald Tract $46,698,005 $4,717,197 no $83,034,205
Medford Island $49,844,151 $2,021,808 no $64,490,958
Quimby Island $58,588,941 $2,413,574 no $76,229,329
Rindge Tract $19,377,561 $5,424,936 no $62,779,497
Venice Island $78,266,313 $4,274,192 no $108,814,011
King Island $35,676,424 $3,112,987 no $59,688,768
Terminous Tract $52,477,120 $76,856,695 yes $106,096,170
Wright-Elmwood Tract -$1,018,725 $3,010,509 yes $22,871,761
Brack Tract $24,427,489 $290,128,755 yes $53,922,074
Canal Ranch Tract $36,037,197 $100,338,229 yes $62,181,291
Dead Horse Island $43,749,388 $882,166 no $49,412,377
Grand Island $254,666,254 $632,108,744 yes $264,094,360
Ryer Island* $25,206,056 $138,815,097 yes $18,937,549
Staten Island $37,335,930 $12,011,078 no $132,246,963
Tyler Island $44,885,632 $8,665,380 no $76,478,961
Coney Island $61,936,649 $1,888,373 no $75,403,846
Jones Tract -$195,060,235 $246,264,918 yes -$156,312,873
Orwood Tract -$87,711,541 $2,905,255 yes -$69,789,340
Palm Tract $60,206,518 $124,503,940 yes $84,965,781
Roberts Island -$113,050,731 $604,431,954 yes $7,900,147
Union Island -$71,464,576 $11,580,883 yes $17,828,227
Victoria Island $71,348,827 $204,987,529 yes $109,501,349
Woodward Island -$51,496,699 $70,569,861 yes -$27,376,199
Bradford Island $78,754,865 $2,547,863 no $96,556,100
Brannan-Andrus Island $186,074,727 $534,606,881 yes $262,128,164
Holland Tract $65,235,932 $3,762,228 no $92,436,639
Jersey Island $58,770,507 $5,298,546 no $98,935,077
Sherman Island -$401,202 $297,394,598 yes $51,774,317
Twitchell Island $70,213,276 $4,087,597 no $94,651,904
Webb Tract $73,454,293 $4,443,922 no $106,838,167
Total for 34 islands $1,279,456,066 $3,629,524,149 $2,498,003,476
* Ryer Island has already been upgraded
pair Decision with PL 84-99 Upgrades Repair Decision with PL 84-99 + 1 ft SLR Upgrades Expected Present Cost of Upgrad
Repair? Repair?
Cost of No Repair (y/n) Cost of Repair Cost of No Repair (y/n) No Upgrade
$45,021,663 no $115,021,684 $52,607,016 no -$23,110,402
$263,356,671 yes $134,415,289 $272,877,286 yes $39,807,517
$31,957,150 no $78,493,092 $35,927,239 no -$6,674,589
$44,930,037 no $98,553,003 $52,499,952 no -$3,648,339
$43,074,117 no $88,472,783 $50,331,342 no -$24,716,518
$18,461,728 no $65,987,631 $21,572,202 no -$4,099,689
$22,039,054 no $78,155,937 $25,752,244 no $608,683
$49,536,696 no $70,486,711 $57,882,752 no -$21,229,625
$39,028,912 no $111,603,371 $45,604,592 no -$2,660,954
$28,425,603 no $63,307,735 $33,214,813 no -$38,421,099
$138,302,415 yes $110,677,851 $149,928,099 yes -$46,344,475
$27,489,845 yes $26,973,347 $32,121,396 yes -$30,758,635
$322,074,627 yes $57,760,154 $328,118,867 yes -$6,523,106
$129,515,181 yes $64,972,072 $135,035,534 yes -$2,647,208
$8,055,318 no $49,410,409 $9,412,496 no -$585,984
$636,719,056 yes $279,800,120 $652,424,815 yes $13,776,553
$138,815,097 yes $24,011,428 $149,530,631 yes -$37,479,006
$109,676,702 no $148,246,412 $128,155,283 no -$11,118,720
$44,966,148 no $85,573,619 $58,297,502 no -$35,855,466
$17,243,293 no $76,610,085 $20,148,482 no -$12,178,715
$298,426,510 yes -$158,516,575 $308,295,614 yes -$333,351,258
$26,528,743 yes -$70,450,875 $30,998,366 yes -$181,637,130
$152,588,948 yes $87,286,364 $157,902,702 yes $25,920,483
$728,463,498 yes $31,561,323 $754,897,272 yes -$165,983,132
$102,668,467 yes $34,029,667 $120,485,210 yes -$163,979,064
$247,168,857 yes $113,856,237 $255,149,670 yes $2,125,356
$95,531,805 yes -$23,410,636 $100,254,667 yes -$94,870,100
$23,265,287 no $97,851,319 $27,185,075 no -$7,264,962
$621,214,409 yes $274,101,607 $642,686,534 yes $915,232
$34,354,020 no $95,172,706 $40,142,064 no -$6,411,050
$48,382,594 no $104,459,157 $56,534,204 no -$6,077,698
$351,830,350 yes $60,039,488 $362,129,730 yes -$59,881,019
$30,605,053 no $99,069,568 $36,893,663 no -$5,810,089
$40,578,762 no $111,199,099 $47,415,564 no -$577,768
$4,960,296,613 $2,684,781,180 $5,252,412,880 -$1,250,741,978
pected Present Cost of Upgrade Alternatives Upgrade and Repair Decisions (Summary)
PL 84-99 PL 84-99 & 1 ft SLR Upgrade Decision Repair Decision
$15,815,519 $22,275,371 No Upgrade no
$84,931,110 $89,775,233 No Upgrade yes
$22,317,397 $25,916,005 No Upgrade no
$36,035,040 $43,291,940 No Upgrade no
$12,993,241 $19,645,592 No Upgrade no
$12,134,145 $15,048,097 No Upgrade no
$20,165,451 $23,812,709 No Upgrade no
$22,523,470 $30,539,015 No Upgrade no
$31,729,531 $37,948,421 No Upgrade no
-$13,747,742 -$9,549,774 No Upgrade no
$7,274,574 $11,856,256 No Upgrade yes
-$6,868,150 -$2,766,563 No Upgrade yes
$22,971,479 $26,809,560 No Upgrade yes
$23,496,886 $26,287,667 No Upgrade yes
$6,532,197 $7,836,579 No Upgrade no
$23,204,659 $38,910,418 No Upgrade yes
-$43,747,512 -$38,673,634 Upgrade yes
$85,666,353 $103,300,008 No Upgrade no
-$1,006,104 $10,946,869 No Upgrade no
$2,832,255 $5,414,466 No Upgrade no
-$294,603,895 -$296,807,597 No Upgrade yes
-$163,714,929 -$164,376,464 No Upgrade yes
$50,679,745 $53,000,328 No Upgrade yes
-$45,032,254 -$21,371,078 No Upgrade yes
-$74,686,261 -$58,484,821 No Upgrade yes
$40,277,878 $44,632,765 No Upgrade yes
-$70,749,600 -$66,784,037 No Upgrade yes
$13,132,559 $16,748,539 No Upgrade no
$76,968,668 $88,942,111 No Upgrade yes
$23,726,066 $29,073,289 No Upgrade no
$36,565,939 $44,295,345 No Upgrade no
-$7,705,500 $559,671 No Upgrade yes
$20,451,561 $26,499,818 No Upgrade no
$35,362,666 $42,013,100 No Upgrade no
$5,926,444 $226,565,203
Repair Decision with No Upgrades Repair Decisio
Confidence in Cost of No
Island Cost of Repair Cost of No Repair Spread Decision Repair
Bacon Island $76,678,539 $4,930,479 $71,748,060 $111,857,412
Bouldin Island $84,447,573 $213,036,975 $128,589,402 $129,571,166
Empire Tract $49,834,790 $2,580,558 $47,254,232 unsure $76,743,814
Mandeville Island $55,466,818 $4,920,445 $50,546,373 $93,111,504
McDonald Tract $46,698,005 $4,717,197 $41,980,809 unsure $83,034,205
Medford Island $49,844,151 $2,021,808 $47,822,343 unsure $64,490,958
Quimby Island $58,588,941 $2,413,574 $56,175,367 $76,229,329
Rindge Tract $19,377,561 $5,424,936 $13,952,625 unsure $62,779,497
Venice Island $78,266,313 $4,274,192 $73,992,121 $108,814,011
King Island $35,676,424 $3,112,987 $32,563,437 unsure $59,688,768
Terminous Tract $52,477,120 $76,856,695 $24,379,574 unsure $106,096,170
Wright-Elmwood Tract -$1,018,725 $3,010,509 $4,029,234 unsure $22,871,761
Brack Tract $24,427,489 $290,128,755 $265,701,267 $53,922,074
Canal Ranch Tract $36,037,197 $100,338,229 $64,301,032 $62,181,291
Dead Horse Island $43,749,388 $882,166 $42,867,222 unsure $49,412,377
Grand Island $254,666,254 $632,108,744 $377,442,489 $264,094,360
Ryer Island $25,206,056 $138,815,097 $113,609,041 $18,937,549
Staten Island $37,335,930 $12,011,078 $25,324,852 unsure $132,246,963
Tyler Island $44,885,632 $8,665,380 $36,220,252 unsure $76,478,961
Coney Island $61,936,649 $1,888,373 $60,048,276 $75,403,846
Jones Tract -$195,060,235 $246,264,918 $441,325,153 -$156,312,873
Orwood Tract -$87,711,541 $2,905,255 $90,616,796 -$69,789,340
Palm Tract $60,206,518 $124,503,940 $64,297,422 $84,965,781
Roberts Island -$113,050,731 $604,431,954 $717,482,685 $7,900,147
Union Island -$71,464,576 $11,580,883 $83,045,459 $17,828,227
Victoria Island $71,348,827 $204,987,529 $133,638,702 $109,501,349
Woodward Island -$51,496,699 $70,569,861 $122,066,560 -$27,376,199
Bradford Island $78,754,865 $2,547,863 $76,207,003 $96,556,100
Brannan-Andrus Island $186,074,727 $534,606,881 $348,532,154 $262,128,164
Holland Tract $65,235,932 $3,762,228 $61,473,703 $92,436,639
Jersey Island $58,770,507 $5,298,546 $53,471,960 $98,935,077
Sherman Island -$401,202 $297,394,598 $297,795,800 $51,774,317
Twitchell Island $70,213,276 $4,087,597 $66,125,680 $94,651,904
Webb Tract $73,454,293 $4,443,922 $69,010,372 $106,838,167
Repair Decision with PL 84-99 Upgrades
Confidence in
Cost of No Repair Spread Decision
$45,021,663 $66,835,749
$263,356,671 $133,785,504
$31,957,150 $44,786,664 unsure
$44,930,037 $48,181,467 unsure
$43,074,117 $39,960,089 unsure
$18,461,728 $46,029,230 unsure
$22,039,054 $54,190,276
$49,536,696 $13,242,801 unsure
$39,028,912 $69,785,099
$28,425,603 $31,263,165 unsure
$138,302,415 $32,206,245 unsure
$27,489,845 $4,618,084 unsure
$322,074,627 $268,152,554
$129,515,181 $67,333,890
$8,055,318 $41,357,059 unsure
$636,719,056 $372,624,695
$138,815,097 $119,877,548
$109,676,702 $22,570,261 unsure
$44,966,148 $31,512,812 unsure
$17,243,293 $58,160,553
$298,426,510 $454,739,382
$26,528,743 $96,318,083
$152,588,948 $67,623,168
$728,463,498 $720,563,350
$102,668,467 $84,840,241
$247,168,857 $137,667,508
$95,531,805 $122,908,003
$23,265,287 $73,290,814
$621,214,409 $359,086,245
$34,354,020 $58,082,618
$48,382,594 $50,552,483
$351,830,350 $300,056,033
$30,605,053 $64,046,851
$40,578,762 $66,259,405
Islands repaired, land values only
Repair Do Not Repair Unsure
Bouldin Island Bacon Island Rindge Tract
Brack Tract Empire Tract Wright-Elmwood Tract
Grand Island Mandeville Island Canal Ranch Tract
Ryer Island McDonald Tract Dead Horse Island
Roberts Island Medford Island Staten Island
Victoria Island Quimby Island Jones Tract
Brannan-Andrus Island Venice Island Palm Tract
Sherman Island King Island Woodward Island
Terminous Tract
Tyler Island
Coney Island
Orwood Tract
Union Island
Bradford Island
Holland Tract
Jersey Island
Twitchell Island
Webb Tract
Islands repaired, including land and asset values
Repair Do Not Repair Unsure
Bouldin Island Bacon Island Empire Tract
Brack Tract Mandeville Island McDonald Tract
Canal Ranch Tract Quimby Island Medford Island
Grand Island Venice Island Rindge Tract
Ryer Island Coney Island King Island
Jones Tract Bradford Island Terminous Tract
Orwood Tract Holland Tract Wright-Elmwood Tract
Palm Tract Jersey Island Dead Horse Island
Roberts Island Twitchell Island Staten Island
Union Island Webb Tract Tyler Island
Victoria Island
Woodward Island
Brannan-Andrus Island
Sherman Island
Guide to Source Data Worksheets
Data Category Worksheet Name Source
Land Uses and Values SD_LUE Lund et. al 2007, Appendix D
Lund et. al 2007 and DRMS Draft Phase 1 (J.R. Benjamin
Land and Asset Values SD_LAV and Associates, 2007)
Levee Repair Costs and PL 84-99 Communications with Delta levee engineers, and
Upgrade Costs SD_RC_PL recorded costs for Twitchell, Sherman, and Bouldin
Cost of 1 ft Extra Levee Height for
SLR, Assumptions and Values SD_1FtSLR Communications with Delta levee engineers
Road and Rail Lengths SD_RR GIS Tele Atlas' StreetMap Premium Data
Costs of No Repair When Delta Road and Rail Lengths (from SD_RR), Communications
Islands Fail SD_NR (1-3) with Delta engineers
Annual Probabilities of Levee DRMS Draft Phase 1 and Draft Phase 2 (J.R. Benjamin
Failure SD_PF and Associates, 2007)
Land Usage and Assigned Values
(Lund, et. al, 2007, Appendix B, using land use data from Department of Water Resources surveys)
Value Table for Different Land Types
Land Type Value/acre
urban $50,000
high-value agriculture $4,500
low-value agriculture $2,250
native vegetation $1,000
Land Usage (acres):
Urban Pasture Alfalfa Field Crops Sugar Beets
Bacon Island 37.8 0.0 0.0 3147.9 0.0
Bethel Tract 642.9 88.8 0.0 0.0 0.0
Bouldin Island 7.8 0.0 0.0 3519.5 0.0
Brack Tract 147.0 104.9 616.5 2566.9 62.0
Bradford Island 53.2 582.4 0.0 41.6 0.0
Brannan-Andrus Island 744.4 183.2 403.1 8600.6 0.0
Canal Ranch 162.5 60.0 376.2 1474.6 655.6
Coney Island 6.8 0.0 504.3 233.7 0.0
Deadhorse Island 0.0 0.0 0.0 0.0 0.0
Empire Tract 2.7 0.0 0.0 2241.2 0.0
Grand Island 416.9 56.2 1804.3 7791.2 368.3
Holland Tract 17.0 231.1 0.0 1528.1 0.0
Hotchkiss Tract 318.3 1594.3 0.0 0.0 0.0
Jersey Island 9.6 2614.1 0.0 0.0 0.0
Jones Tract 128.4 0.0 802.8 4332.9 0.0
King Island 37.6 0.0 0.0 889.2 0.0
Mandeville Island 19.5 68.7 0.0 2251.6 0.0
McDonald Tract 60.9 454.0 0.0 985.2 0.0
Medford Island 5.0 0.0 0.0 621.1 0.0
Orwood Tract 49.8 0.0 216.8 1306.6 0.0
Palm Tract 5.3 148.4 209.3 1280.0 0.0
Quimby Island 0.0 0.0 0.0 621.1 0.0
Rindge Tract 25.1 0.0 0.0 4508.7 0.0
Roberts Island 1297.2 136.3 8304.7 9359.6 304.0
Ryer Island 107.6 0.0 865.7 3621.6 563.6
Sherman Island 115.1 3429.5 34.9 3791.0 0.0
Staten Island 26.8 0.0 0.0 4565.6 0.0
Terminous Tract 401.5 353.3 1092.7 5546.6 245.9
Twitchell Island 27.6 503.7 0.0 1978.4 0.0
Tyler Island 211.0 8.9 181.4 3682.0 230.6
Union Island 187.5 262.1 7658.1 6990.1 1310.5
Venice Island 7.1 0.0 0.0 2695.9 0.0
Victoria Island 39.4 0.0 1038.4 2832.2 0.0
Webb Tract 6.4 0.0 0.0 2772.3 0.0
Woodward Island 4.9 0.0 0.0 1249.1 0.0
Wright-Elmwood Tract 407.4 0.0 0.0 511.1 214.5
Native
Grain Rice Truck Tomato Orchards Vineyards Riparian
851.9 0.0 1097.1 0.0 0.0 0.0 0.0
0.0 0.0 0.0 0.0 0.0 0.0 51.4
1831.0 0.0 0.0 0.0 0.0 0.0 25.1
1072.4 0.0 0.0 306.1 5.5 878.5 0.0
0.0 0.0 0.0 0.0 0.0 0.0 109.4
1727.2 0.0 761.2 0.0 785.9 676.4 222.4
506.9 0.0 0.0 1396.3 0.0 1367.3 51.4
166.7 0.0 0.0 0.0 0.0 0.0 0.0
0.0 0.0 0.0 187.5 0.0 0.0 0.0
666.3 0.0 489.9 0.0 0.0 0.0 53.7
2166.9 0.0 206.5 955.8 2286.0 39.8 41.9
1252.8 0.0 0.0 0.0 0.0 0.0 88.6
0.0 0.0 0.0 0.0 0.0 0.0 26.3
0.0 0.0 0.0 0.0 0.0 0.0 19.0
1627.4 0.0 4468.0 0.0 0.0 0.0 1.2
719.8 0.0 1134.7 292.3 4.7 0.0 0.0
1083.0 0.0 6.0 0.0 0.0 369.3 204.5
1104.8 0.0 2381.5 0.0 12.4 8.4 114.4
0.0 0.0 0.0 0.0 0.0 0.0 425.5
0.0 0.0 632.9 0.0 0.0 0.0 0.0
371.9 0.0 0.0 0.0 0.0 0.0 43.5
0.0 0.0 0.0 0.0 0.0 0.0 12.4
321.1 0.0 1677.7 0.0 0.0 0.0 0.0
5131.7 0.0 5623.2 3175.5 267.8 1087.4 67.2
3195.4 0.0 0.0 2125.6 462.0 619.9 37.3
1575.3 0.0 6.4 0.0 0.0 2.5 219.7
1854.5 13.4 554.2 1716.8 0.0 0.0 0.0
2092.0 0.0 973.9 684.1 0.0 380.5 152.0
731.2 0.0 0.0 0.0 15.0 0.0 61.0
1799.5 0.0 861.6 536.1 284.5 62.3 41.9
1795.8 0.0 2669.0 2970.3 481.8 492.0 52.6
0.0 0.0 6.3 0.0 0.0 0.0 9.8
716.5 0.0 2206.1 0.0 0.0 0.0 0.0
1919.2 0.0 0.0 0.0 0.0 0.0 129.7
132.6 0.0 239.8 0.0 0.0 0.0 0.0
656.5 0.0 144.9 390.3 0.0 0.0 8.1
Land value ($)
Non- "Z" &
Water irrigated Native "Blank" Total High Value Low Value
Surface Grain Vegetation Crops Acreage Urban Agricutlure Agriculture
74.5 0.0 423.4 0.0 5632.6 1,888,357 8,999,643 4,937,063
42.6 0.0 2718.1 0.0 3543.7 32,144,535 199,842 0
101.5 0.0 586.8 0.0 6071.7 390,017 12,038,592 0
52.1 0.0 550.0 0.0 6361.9 7,348,271 9,951,294 5,355,541
69.9 0.0 1347.5 0.0 2204.0 2,657,836 1,404,009 0
285.5 0.0 1170.5 0.0 15560.3 37,218,129 24,556,791 10,005,357
41.0 0.0 166.8 0.0 6258.6 8,123,317 6,915,136 12,435,937
2.6 0.0 62.8 0.0 976.9 339,917 2,035,559 0
14.4 0.0 18.7 0.0 220.7 0 0 843,842
45.3 0.0 179.7 0.0 3678.7 134,860 6,542,024 2,204,365
183.1 0.0 670.1 0.0 16987.1 20,843,875 27,420,859 15,696,491
67.4 0.0 1105.6 0.0 4290.5 852,315 6,776,893 0
65.1 0.0 1355.0 0.2 3359.2 15,913,449 3,587,117 0
61.7 0.0 890.1 0.0 3594.6 482,103 5,881,734 0
231.4 0.0 753.8 0.0 12345.8 6,418,243 15,216,946 20,105,971
36.4 0.0 138.9 0.0 3253.7 1,879,434 3,620,157 6,443,077
92.1 0.0 1206.2 0.0 5300.9 974,257 7,657,413 1,688,878
180.1 0.0 899.7 0.0 6201.3 3,043,427 5,724,026 10,810,391
25.8 0.0 147.8 0.0 1225.3 250,367 1,397,481 0
27.8 0.0 126.1 0.0 2360.0 2,491,364 3,427,739 2,847,852
31.0 0.0 518.5 0.0 2607.8 262,918 4,521,722 0
26.3 0.0 155.8 0.0 815.6 0 1,397,476 0
120.5 0.0 234.7 0.0 6887.8 1,254,922 10,866,950 7,549,846
385.2 0.0 1201.5 0.0 36341.3 64,860,371 52,281,474 45,692,621
279.0 0.0 262.7 0.2 12140.5 5,382,487 18,554,134 14,433,488
243.0 0.0 1138.1 0.0 10555.5 5,756,462 19,869,073 39,876
191.2 0.0 373.6 0.0 9296.1 1,341,241 14,475,481 10,219,397
202.1 0.0 580.1 0.0 12704.8 20,076,496 20,993,595 9,173,241
100.0 0.0 285.2 0.0 3702.2 1,379,475 7,229,988 67,641
160.5 0.0 1477.5 0.0 9538.0 10,552,487 13,280,809 7,850,069
414.2 0.0 948.4 0.0 26232.4 9,375,290 40,537,336 29,758,970
181.2 0.0 381.6 0.0 3281.9 354,424 6,065,748 28,374
46.4 0.0 399.7 0.0 7278.8 1,970,376 10,321,042 9,927,642
154.8 0.0 546.6 0.0 5529.0 322,283 10,555,929 0
51.0 0.0 206.6 0.0 1883.9 243,001 3,108,969 1,079,054
121.4 0.0 270.2 0.0 2724.4 20,369,439 3,109,863 2,408,579
Native Total Value
Vegetation ($)
423,360 16,248,424
2,769,426 35,113,803
611,933 13,040,542
549,990 23,205,096
1,456,997 5,518,842
1,392,900 73,173,177
218,154 27,692,544
62,779 2,438,255
18,740 862,581
233,357 9,114,605
712,010 64,673,235
1,194,135 8,823,343
1,381,337 20,881,903
909,124 7,272,961
755,003 42,496,164
138,945 12,081,613
1,410,656 11,731,203
1,014,005 20,591,848
573,297 2,221,145
126,079 8,893,034
561,953 5,346,593
168,211 1,565,687
234,676 19,906,394
1,268,764 164,103,230
299,959 38,670,068
1,357,755 27,023,167
373,558 26,409,675
732,166 50,975,498
346,263 9,023,367
1,519,394 33,202,759
1,000,972 80,672,567
391,417 6,839,964
399,727 22,618,787
676,254 11,554,466
206,556 4,637,580
278,239 26,166,120
Land and Asset Values
Asset Value
Land Value (J.R. Benjamin & Land + Asset
Island Name (Lund et al, 2007) Associates, 2007) Values
Bacon Island $16,248,424 $43,916,000 $60,164,424
Bouldin Island $13,040,542 $25,897,000 $38,937,542
Empire Tract $9,114,605 $9,790,000 $18,904,605
Mandeville Island $11,731,203 $5,212,000 $16,943,203
McDonald Tract $20,591,848 $36,246,000 $56,837,848
Medford Island $2,221,145 $8,559,000 $10,780,145
Quimby Island $1,565,687 $626,000 $2,191,687
Rindge Tract $19,906,394 $18,516,000 $38,422,394
Venice Island $6,839,964 $13,308,000 $20,147,964
King Island $12,081,613 $44,049,000 $56,130,613
Terminous Tract $50,975,498 $93,400,000 $144,375,498
Wright-Elmwood Tract $26,166,120 $16,429,000 $42,595,120
Brack Tract $23,205,096 $14,021,000 $37,226,096
Canal Ranch Tract $27,692,544 $20,757,000 $48,449,544
Dead Horse Island $862,581 $998,000 $1,860,581
Grand Island $64,673,235 $253,978,000 $318,651,235
Ryer Island $38,670,068 $61,494,000 $100,164,068
Staten Island $26,409,675 $20,596,000 $47,005,675
Tyler Island $33,202,759 $92,866,000 $126,068,759
Coney Island $2,438,255 $21,921,000 $24,359,255
Jones Tract $42,496,164 $507,972,000 $550,468,164
Orwood Tract $8,893,034 $251,172,000 $260,065,034
Palm Tract $5,346,593 $22,562,000 $27,908,593
Roberts Island $164,103,230 $64,446,000 $228,549,230
Union Island $80,672,567 $156,763,000 $237,435,567
Victoria Island $22,618,787 $57,078,000 $79,696,787
Woodward Island $4,637,580 $124,671,000 $129,308,580
Bethel Tract $35,113,803 $254,118,000 $289,231,803
Bradford Island $5,518,842 $21,630,000 $27,148,842
Brannan-Andrus Island $73,173,177 $216,612,000 $289,785,177
Holland Tract $8,823,343 $15,787,000 $24,610,343
Hotchkiss Tract $20,881,903 $128,181,000 $149,062,903
Jersey Island $7,272,961 $24,614,000 $31,886,961
Sherman Island $27,023,167 $114,940,000 $141,963,167
Twitchell Island $9,023,367 $14,493,000 $23,516,367
Webb Tract $11,554,466 $416,000 $11,970,466
Levee Repair and PL 84-99 Upgrade Costs
Elevation in
2000 (m Levee Length Area Volume
Zone Island name msl) (m) (m^2) (m^3)
Central Bacon Island -4.82 23,094 22,820,772 109,996,122
Central Bouldin Island -5.09 28,986 24,600,090 125,266,120
Central Empire Tract -5.13 16,922 14,894,662 76,338,123
Central Mandeville Island -5.36 23,047 21,470,227 115,071,826
Central McDonald Tract -4.65 22,095 25,115,537 116,769,666
Central Medford Island -2.45 9,470 4,960,941 12,136,942
Central Quimby Island -2.22 11,305 3,304,082 7,345,966
Central Rindge Tract -4.38 25,410 27,903,064 122,340,983
Central Venice Island -4.29 20,020 13,288,295 56,957,619
Eastern King Island -2.38 14,581 13,172,792 31,320,946
Eastern Terminous Tract -1.52 35,395 51,439,035 78,315,930
Eastern Wright-Elmwood Tract -2.10 14,101 11,035,876 23,190,789
Northern Brack Tract -1.41 18,402 25,784,836 36,480,387
Northern Canal Ranch Tract -0.97 16,807 25,341,752 24,540,952
Northern Dead Horse Island -2.06 4,132 899,779 1,857,233
Northern Grand Island -0.98 47,817 68,775,422 67,331,139
Northern Ryer Island -1.88 32,624 49,140,461 92,403,722
Northern Staten Island -3.29 56,259 37,634,620 123,817,898
Northern Tyler Island -2.61 40,588 38,620,444 100,826,393
Southern Coney Island -0.16 8,845 3,955,484 625,758
Southern Jones Tract -3.26 30,047 49,983,648 163,111,638
Southern Orwood Tract -2.52 13,608 9,556,957 24,128,449
Southern Palm Tract -3.08 16,178 10,559,468 32,548,504
Southern Roberts Island -0.73 80,479 147,209,168 107,889,599
Southern Union Island -0.27 54,244 106,242,276 28,164,827
Southern Victoria Island -3.16 24,298 29,475,222 93,215,390
Southern Woodward Island -3.27 14,379 7,628,998 24,966,660
Western Bethel Tract -1.99 18,456 14,349,714 28,623,374
Western Bradford Island -2.24 11,934 8,924,908 19,955,203
Western Brannan-Andrus Island -2.81 65,373 63,004,232 176,922,184
Western Holland Tract -3.73 17,622 17,377,522 64,736,484
Western Hotchkiss Tract -0.94 18,702 13,604,706 12,845,564
Western Jersey Island -2.34 24,818 14,556,280 34,029,670
Western Sherman Island -3.73 31,357 42,743,906 159,537,354
Western Twitchell Island -3.17 19,146 14,988,214 47,538,118
Western Webb Tract -5.15 20,815 22,398,376 115,322,520
Total 931,356 1,056,761,765 2,456,470,053
*Assumes $2.8m/mi for PL 84-99 upgrade
Pl-84-99 Upgrade based on Bouldin Island example: 30 yards/ft total fill
5$/yd on-island, $15/yd off island fill source
20%/yd engineering
$15/ft riprap
**Assumes $25m to repair breach and, scaled to Jones tract failure total of $80M repairs and costs, counting breach, for $.3
**Single Breach
PL 84-99 Repair/Damage
Upgrade* Costs
$40,091,184 $62,398,682
$50,319,696 $67,590,481
$29,376,592 $50,954,962
$40,009,592 $64,124,421
$38,356,920 $64,701,686
$16,439,920 $29,126,560
$19,625,480 $27,497,629
$44,111,760 $66,595,934
$34,754,720 $44,365,590
$25,312,616 $35,649,122
$61,445,720 $51,627,416
$24,479,336 $32,884,868
$31,945,872 $37,403,331
$29,176,952 $33,343,924
$7,173,152 $25,631,459
$83,010,312 $47,892,587
$56,635,264 $56,417,266
$97,665,624 $67,098,085
$70,460,768 $59,280,973
$15,354,920 $25,212,758
$52,161,592 $80,457,957
$23,623,488 $33,203,673
$28,085,008 $36,066,491
$139,711,544 $61,682,464
$94,167,584 $34,576,041
$42,181,328 $56,693,233
$24,961,944 $33,488,664
$32,039,616 $34,731,947
$20,717,424 $31,784,769
$113,487,528 $85,153,542
$30,591,792 $47,010,405
$32,466,672 $29,367,492
$43,084,048 $36,570,088
$54,435,752 $79,242,700
$33,237,456 $41,162,960
$36,134,840 $64,209,657
$1,616,834,016 $1,735,199,818
osts, counting breach, for $.34/m^3
Materials and Cost of 1 ft SLR
Assumptions and Formulas:
1. All levees were given an initial height of 25 feet, which is an average value for levee heights in the
Delta. Data are currently lacking to calculate the actual heights of levees on individual islands.
2. The amount of fill needed for a cross section of levee with given height was calculated using the
following formula:
f(x) = h^2 + 21h + 3/4*h^2 + 3/8*h^2 + 10/8*h^2
3. This is a simplified geometric formula obtained by assuming the following: (1) a crown width of 21
feet; (2) a 2:1 slope on the backside (or water side); (3) a 3:1 slope on the land side until an elevation
equal to 1/2 the total height of the levee, and from that point on a 10:1 slope to the existing ground
(10:1 slope being the slope of the toe berm).
3. The amount of additional fill needed for unit increases in height was calculated by taking the
amount of cross-sectional fill needed to build a levee of that height (formula shown above),
multiplying by the length of the levee, dividing by 27 to get cubic yards, and finally subtracting the
original amount of fill needed to build a levee of height = 25 feet.
4. A one-to-one relationship was assumed in terms of amount of sea level rise in relation to needed
levee height.
5. Costs were calculated based upon the following assumptions: (1) one cubic yard of fill = 1.4 cut
yards; (2) one cut yard costs a minimum of $5.00 for on-island sourcing, $15 for off-island, yielding an
average minimum cost of $10.00 per cut yard (this also assumes that fill is obtained from on-island
borrowing approximately 50% of the time); (3) total costs = 10 * amt of cut yrds.
6. Island Value includes land and asset values (see SD_LAV)
Values:
Materials Cost to Raise
Island the Levee 1'
Bacon Island $7,585,353
Bouldin Island $9,520,615
Empire Tract $3,970,089
Mandeville Island $7,569,915
McDonald Tract $7,257,226
Medford Island $3,110,474
Quimby Island $3,713,190
Rindge Tract $8,346,056
Venice Island $6,575,680
King Island $4,789,210
Terminous Tract $11,625,684
Wright-Elmwood Tract $4,631,552
Brack Tract $6,044,239
Canal Ranch Tract $5,520,353
Dead Horse Island $1,357,178
Grand Island $15,705,759
Ryer Island $10,715,534
Staten Island $18,478,581
Tyler Island $13,331,354
Coney Island $2,905,189
Jones Tract $9,869,104
Orwood Tract $4,469,623
Palm Tract $5,313,754
Roberts Island $26,433,775
Union Island $17,816,743
Victoria Island $7,980,813
Woodward Island $4,722,862
Bethel Tract $6,061,976
Bradford Island $3,919,789
Brannan-Andrus Island $21,472,125
Holland Tract $5,788,044
Hotchkiss Tract $6,142,776
Jersey Island $8,151,610
Sherman Island $10,299,381
Twitchell Island $6,288,610
Webb Tract $6,836,802
Lengths of Road and Rail on Interior of Delta Islands
(Length of road and/or rail on levees not included)
Island Name Highway 4 Highway 12 Highway 160 Other Highway Total Highway
Bishop 0.00 0.00 0.00 2.00 2.00
Bouldin 0.00 4.60 0.00 0.00 4.60
Brack 0.00 6.36 0.00 0.00 6.36
Brannan-Andrus 0.00 5.73 5.84 0.00 11.57
Byron 4.85 0.00 0.00 0.00 4.85
Canal Ranch 0.00 0.00 0.00 0.00 0.00
Grand 0.00 0.00 13.82 0.00 13.82
Jones 0.00 0.00 0.00 0.00 0.00
Lisbon 0.00 0.00 0.00 0.00 0.00
Netherlands 0.00 0.00 0.00 0.00 0.00
New Hope Ranch 0.00 0.00 0.00 2.76 2.76
Palm 0.00 0.00 0.00 0.00 0.00
Pierson 0.00 0.00 1.89 0.00 1.89
Rio Blanco 0.00 0.00 0.00 1.00 1.00
Roberts 6.46 0.00 0.00 0.00 6.46
Rough and Ready 0.00 0.00 0.00 0.00 0.00
Ryer 0.00 0.00 0.00 0.00 0.00
Sargent Barnhart 0.00 0.00 0.00 5.06 5.06
Sherman 0.00 0.00 6.46 0.00 6.46
Shima 0.00 0.00 0.00 2.79 2.79
Shin Kee 0.00 0.00 0.00 2.00 2.00
Stewart 0.00 0.00 0.00 3.71 3.71
Sutter 0.00 0.00 1.80 0.00 1.80
Terminous 0.00 0.00 0.00 1.54 1.54
Tyler 0.00 0.00 0.00 0.00 0.00
Veale 13.57 0.00 0.00 0.26 13.83
Victoria 4.44 0.00 0.00 0.00 4.44
Walnut Grove 0.00 0.00 0.00 0.00 0.00
Woodward 0.00 0.00 0.00 0.00 0.00
Total Rail
0.00
0.00
0.00
0.00
6.31
2.15
0.00
5.33
3.08
7.48
5.08
2.69
0.00
0.00
6.59
7.44
2.93
0.00
0.00
0.00
0.00
3.11
0.00
0.00
7.96
13.43
0.00
1.45
1.50
No Repair Costs 1: Costs of Upgrades to Nearby Islands
Cost to Raise Levee 1 Cost to Build up
Island ft Surrounding Islands
Bacon Island $7,585,353 $4,930,479 Assumptions
Bouldin Island $9,520,615 $6,188,400 1. If an island fails permanently, surro
Empire Tract $3,970,089 $2,580,558 pressure from wind and waves, which
Mandeville Island $7,569,915 $4,920,445 2. The (very) approximate length of le
McDonald Tract $7,257,226 $4,717,197 islands should be equal to roughly ha
Medford Island $3,110,474 $2,021,808 (geometrically).
Quimby Island $3,713,190 $2,413,574 3. The surrounding levees will need to
Rindge Tract $8,346,056 $5,424,936 increased exposure
Venice Island $6,575,680 $4,274,192 4. Cost of these upgrades should thus
King Island $4,789,210 $3,112,987 raising the levee of the failed island b
Terminous Tract $11,625,684 $7,556,695 "Levee_Rise_Costs1" * 1.3
Wright-Elmwood Tract $4,631,552 $3,010,509 5. The multiplier of 1.3 accounts for 2
Brack Tract $6,044,239 $3,928,755 management and 10% state costs.
Canal Ranch Tract $5,520,353 $3,588,229
Dead Horse Island $1,357,178 $882,166
Grand Island $15,705,759 $10,208,744
Ryer Island $10,715,534 $6,965,097
Staten Island $18,478,581 $12,011,078
Tyler Island $13,331,354 $8,665,380
Coney Island $2,905,189 $1,888,373
Jones Tract $9,869,104 $6,414,918
Orwood Tract $4,469,623 $2,905,255
Palm Tract $5,313,754 $3,453,940
Roberts Island $26,433,775 $17,181,954
Union Island $17,816,743 $11,580,883
Victoria Island $7,980,813 $5,187,529
Woodward Island $4,722,862 $3,069,861
Bethel Tract $6,061,976 $3,940,284
Bradford Island $3,919,789 $2,547,863
Brannan-Andrus Island $21,472,125 $13,956,881
Holland Tract $5,788,044 $3,762,228
Hotchkiss Tract $6,142,776 $3,992,804
Jersey Island $8,151,610 $5,298,546
Sherman Island $10,299,381 $6,694,598
Twitchell Island $6,288,610 $4,087,597
Webb Tract $6,836,802 $4,443,922
1. If an island fails permanently, surrounding islands are then exposed to increased
pressure from wind and waves, which must be mitigated.
2. The (very) approximate length of levee upgrades needed to these surrounding
islands should be equal to roughly half the circumference of the failed island
(geometrically).
3. The surrounding levees will need to be raised 1 foot in order to account for this
increased exposure
4. Cost of these upgrades should thus be equal to HALF the cost of materials for
raising the levee of the failed island by one foot (obtained from spreadsheet titled
"Levee_Rise_Costs1" * 1.3
5. The multiplier of 1.3 accounts for 20% cost for engineers and construction
management and 10% state costs.
No Repair Costs 2: Infrastructure Replacement Costs
Miles of Miles of Total Cost to
Island Railroad Highway Replace
Bacon Island 0 0 $0 Assumptions
Bouldin Island 0 4.60 $206,848,575
Empire Tract 0 0 $0 1. Cost calculations are based on a simpl
Mandeville Island 0 0 $0 obtained from DRMS Preliminary Strateg
McDonald Tract 0 0 $0 Armored Infrastructure Corridor Cost Es
Medford Island 0 0 $0 Associates, 2007), of 45 million dollars p
Quimby Island 0 0 $0 levee. We assumed that these levees w
Rindge Tract 0 0 $0 build the roads or highways on top of th
Venice Island 0 0 $0 2. These costs are conservative in that th
King Island 0 0 $0 the actual cost of the road or rails thems
Terminous Tract 0 1.54 $69,300,000
Wright-Elmwood Tract 0 0 $0
Brack Tract 0 6.36 $286,200,000
Canal Ranch Tract 2.15 0 $96,750,000
Dead Horse Island 0 0 $0
Grand Island 0 13.82 $621,900,000
Ryer Island 2.93 0 $131,850,000
Staten Island 0 0 $0
Tyler Island 0 0 $0
Coney Island 0 0 $0
Jones Tract 5.33 0 $239,850,000
Orwood Tract 0 0 $0
Palm Tract 2.69 0 $121,050,000
Roberts Island 6.59 6.46 $587,250,000
Union Island 0 0 $0
Victoria Island 0 4.44 $199,800,000
Woodward Island 1.5 0 $67,500,000
Bethel Tract 0 0 $0
Bradford Island 0 0 $0
Brannan-Andrus Island 0 11.57 $520,650,000
Holland Tract 0 0 $0
Hotchkiss Tract 0 0 $0
Jersey Island 0 0 $0
Sherman Island 0 6.46 $290,700,000
Twitchell Island 0 0 $0
Webb Tract 0 0 $0
. Cost calculations are based on a simple, per mile estimated cost
btained from DRMS Preliminary Strategies Report Section 12 -
rmored Infrastructure Corridor Cost Estimates (J.R. Benjamin and
ssociates, 2007), of 45 million dollars per mile of seismically resistant
vee. We assumed that these levees would have to be put in place to
uild the roads or highways on top of them.
. These costs are conservative in that they do not take into account
he actual cost of the road or rails themselves.
No Repair Costs 3: Total Costs of a Flooded Island
Total Cost of Not
Cost of Road and Cost of Surrounding Repairing a
Island Rail Upgrades Flooded Island
Bacon Island $0 $4,930,479 $4,930,479 Assumptions
Bouldin Island $206,848,575 $6,188,400 $213,036,975 This cost of no repair is based u
Empire Tract $0 $2,580,558 $2,580,558 1. An estimated cost of replaci
Mandeville Island $0 $4,920,445 $4,920,445 infrastructure (SD_NR2)
McDonald Tract $0 $4,717,197 $4,717,197 2. An estimated cost of strengt
Medford Island $0 $2,021,808 $2,021,808 islands (SD_NR1)
Quimby Island $0 $2,413,574 $2,413,574 These two factors are assumed to
Rindge Tract $0 $5,424,936 $5,424,936 elements.
Venice Island $0 $4,274,192 $4,274,192
King Island $0 $3,112,987 $3,112,987
Terminous Tract $69,300,000 $7,556,695 $76,856,695
Wright-Elmwood Tract $0 $3,010,509 $3,010,509
Brack Tract $286,200,000 $3,928,755 $290,128,755
Canal Ranch Tract $96,750,000 $3,588,229 $100,338,229
Dead Horse Island $0 $882,166 $882,166
Grand Island $621,900,000 $10,208,744 $632,108,744
Ryer Island $131,850,000 $6,965,097 $138,815,097
Staten Island $0 $12,011,078 $12,011,078
Tyler Island $0 $8,665,380 $8,665,380
Coney Island $0 $1,888,373 $1,888,373
Jones Tract $239,850,000 $6,414,918 $246,264,918
Orwood Tract $0 $2,905,255 $2,905,255
Palm Tract $121,050,000 $3,453,940 $124,503,940
Roberts Island $587,250,000 $17,181,954 $604,431,954
Union Island $0 $11,580,883 $11,580,883
Victoria Island $199,800,000 $5,187,529 $204,987,529
Woodward Island $67,500,000 $3,069,861 $70,569,861
Bethel Tract $0 $3,940,284 $3,940,284
Bradford Island $0 $2,547,863 $2,547,863
Brannan-Andrus Island $520,650,000 $13,956,881 $534,606,881
Holland Tract $0 $3,762,228 $3,762,228
Hotchkiss Tract $0 $3,992,804 $3,992,804
Jersey Island $0 $5,298,546 $5,298,546
Sherman Island $290,700,000 $6,694,598 $297,394,598
Twitchell Island $0 $4,087,597 $4,087,597
Webb Tract $0 $4,443,922 $4,443,922
his cost of no repair is based upon:
. An estimated cost of replacing lost transportation
frastructure (SD_NR2)
An estimated cost of strengthening surrounding
lands (SD_NR1)
hese two factors are assumed to be the most significant cost
ements.
Annual Probabilities of Levee Failures
PL-84-99 PL 84 99 + DRMS Pf DRMS
Island Name* Annual Pf 2000 Pf 1' 2000 Pf Flood Seismic Pf
Staten Island 0.07 0.06 0.06 0.04 0.03
Brannan-Andrus Island 0.07 0.06 0.05 0.03 0.05
Bouldin Island 0.05 0.05 0.04 0.06 0.03
Mandeville Island 0.05 0.04 0.04 0.04 0.03
Sherman Island 0.04 0.04 0.04 0.02 0.05
Rindge Tract 0.04 0.04 0.03 0.01 0.02
Bacon Island 0.04 0.04 0.03 0.04 0.02
Webb Tract 0.04 0.04 0.03 0.05 0.05
Tyler Island 0.04 0.04 0.03 0.04 0.05
McDonald Tract 0.04 0.03 0.03 0.02 0.03
Jones Tract 0.04 0.03 0.03 0.05 0.03
Empire Tract 0.03 0.03 0.03 0.04 0.02
Venice Island 0.03 0.03 0.03 0.07 0.04
Victoria Island 0.03 0.03 0.02 0.03 0.03
Holland Tract 0.02 0.02 0.02 0.05 0.03
Ryer Island 0.02 0.02 0.02 0.02 0.03
Twitchell Island 0.02 0.02 0.02 0.03 0.05
Roberts Island 0.02 0.02 0.02 0.03 0.03
Jersey Island 0.02 0.02 0.02 0.05 0.05
Terminous Tract 0.02 0.02 0.02 0.04 0.01
Palm Tract 0.02 0.02 0.02 0.05 0.03
Woodward Island 0.02 0.02 0.01 0.01 0.03
Grand Island 0.02 0.02 0.01 0.02 0.05
Bethel Tract 0.01 0.01 0.01 0.04 0.05
King Island 0.01 0.01 0.01 0.01 0.01
Orwood Tract 0.01 0.01 0.01 0.03 0.01
Wright-Elmwood Tract 0.01 0.01 0.01 0.01 0.01
Bradford Island 0.01 0.01 0.01 0.04 0.05
Brack Tract 0.01 0.01 0.01 0.04 0.01
Quimby Island 0.01 0.01 0.01 0.04 0.03
Medford Island 0.01 0.01 0.01 0.03 0.02
Hotchkiss Tract 0.01 0.01 0.01 0.01 0.03
Canal Ranch Tract 0.01 0.01 0.00 0.04 0.02
Union Island 0.01 0.00 0.00 0.01 0.03
Dead Horse Island 0.00 0.00 0.00 0.03 0.01
Coney Island 0.00 0.01 0.01 0.02 0.02
Average Value 0.03 0.02 0.02 0.03 0.03
*Island in blue Western island important for water quality at the southern Delta pumps
*Island in bold Major roadway, aqueduct, pipeline or railroad infrastructure
DRMS PL 84-
DRMS 84-99 DRMS PL 84- 99 +1' Raise
DRMS Flood DRMS Flood Flood + 99 + 1' Raise Flood +
+ Seismic PL 84-99 Seismic Flood Seismic DRMS Estimates
0.07 0.04 0.06 0.03 0.06
0.08 0.03 0.08 0.02 0.07 Atlas Tract
0.09 0.05 0.08 0.05 0.08 Bacon Island
0.07 0.04 0.06 0.03 0.06 Bethel Island
0.07 0.02 0.07 0.02 0.07 Bishop Tract
0.03 0.01 0.03 0.01 0.03 Bixler Tract
0.06 0.04 0.06 0.03 0.05 Boggs Tract
0.10 0.05 0.09 0.04 0.09 Bouldin Island
0.09 0.04 0.08 0.03 0.08 Brack Tract
0.05 0.02 0.05 0.02 0.05 Bradford Island
0.08 0.05 0.07 0.04 0.07 Brannan-Andrus Island
0.06 0.04 0.06 0.03 0.05 MERGE Upper Andrus Island
0.11 0.06 0.10 0.06 0.09 Byron Tract
0.06 0.03 0.06 0.02 0.05 Cache Haas Area
0.08 0.05 0.07 0.04 0.07 Canal Ranch
0.05 0.02 0.05 0.02 0.05 Clifton Court Forebay South
0.08 0.03 0.08 0.02 0.07 Coney Island
0.06 0.03 0.06 0.02 0.05 Cosumnes River Area
0.10 0.05 0.09 0.04 0.09 Deadhorse Island
0.05 0.04 0.05 0.03 0.04 Dutch Slough
0.08 0.05 0.07 0.04 0.07 Egbert Tract
0.04 0.01 0.04 0.01 0.04 Little Egbert Tract
0.07 0.02 0.07 0.02 0.07 Ehrheardt Club
0.09 0.04 0.08 0.03 0.08 Elk Grove
0.02 0.01 0.02 0.01 0.02 Empire Tract
0.04 0.03 0.04 0.02 0.04 Fabian Tract
0.02 0.01 0.02 0.01 0.02 Fay Island
0.09 0.04 0.08 0.03 0.08 Glanville Tract
0.05 0.04 0.05 0.03 0.04 Glide District
0.07 0.04 0.06 0.03 0.06 Grand Island
0.05 0.03 0.05 0.02 0.04 Hastings Tract
0.04 0.01 0.04 0.01 0.04 Holland Tract
0.06 0.04 0.06 0.03 0.05 Hotchkiss Tract
0.04 0.01 0.04 0.01 0.04 Jersey Island
0.04 0.03 0.04 0.02 0.03 Kasson District
0.04 0.02 0.04 0.02 0.04 King Island
0.06 0.03 0.06 0.03 0.06 Libby McNeil Tract 1
Liberty Island
n Delta pumps . Lisbon District + Glide
Little Mandeville
Lower Jones Tract
MERGE Upper Jones Tract
Mandeville Island
McCormack Williamson Tract
McDonald Tract
McMullin Ranch
Medford Island
Merritt Island
Middle Roberts Island
MERGE Drexler Tract
MERGE Holt Station
MERGE Lower Roberts Island
MERGE Upper Roberts Island
Netherlands
New Hope Tract
Palm-Orwood Tract
Paradise Junction
Pescadero
Peter's Pocket
Pico Naglee Tract
Pierson Tract
MERGE Randall Island
Prospect Island
Quimby Island
RD 17 (Mossdale)
Rindge Tract
Rio Blanco Tract
River Junction Tract
Rough and Ready Island
Ryer Island
Sacramento Pocket Area
Sargent Barnhart Tract East
Sherman Island
Shima Tract
Shin Kee Tract
Smith Tract
Stark Tract
Staten Island
Stewart Tract
MERGE Mossdale RD 2107
Sutter Island
Terminous Tract
Tinsley Island
Twitchell Island
Tyler Island
Union Island
Veale Tract
Venice Island
Victoria Island
Walnut Grove
Walthal Tract
MERGE Wetherbee Lake
Webb Tract
Weber Tract
West Sacramento
Woodward Island
Wright-Elmwood Tract
Seismic risk (annual frequency of failure)
Flood risk (annual frequency of failure)
0.01 0.01
0.04 0.02
0.04 0.05
0.03 0.01
0.01 0.01
0.06 0.03
0.04 0.01
0.04 0.05
0.03 0.05
0.02 0.03
0.05 0.02
0.04 0.02
0.01 0.01
0.02 0.02
0.05 0.01
0.03 0.01
0.01 0.02
0.03 0.02
0.07 0.02
0.07 0.02
0.02 0.01
0.04 0.02
0.02 0.03
0.06 0.01
0.01 0.02
0.02 0.05
0.04 0.04
0.05 0.03
0.01 0.03
0.05 0.05
0.01 0.01
0.01 0.01
0.01 0.01
0.01 0.03
0.04 0.02
0.05 0.03
0.04 0.03
0.04 0.01
0.02 0.03
0.02 0.01
0.03 0.02
0.01 0.02
0.03 0.03
0.01 0.02
0.05 0.02
0.05 0.03
0.03 0.01
0.03 0.01
0.07 0.03
0.01 0.01
0.01 0.03
0.01 0.01
0.04 0.03
0.03 0.01
0.01 0.02
0.01 0.01
0.03 0.01
0.01 0.01
0.02 0.03
0.01 0.01
0.02 0.01
0.02 0.05
0.03 0.01
0.02 0.01
0.01 0.01
0.01 0.01
0.04 0.03
0.01 0.01
0.01 0.02
0.04 0.01
0.04 0.02
0.03 0.05
0.04 0.05
0.01 0.03
0.01 0.01
0.07 0.04
0.03 0.03
0.02 0.01
0.01 0.01
0.05 0.05
0.01 0.01
0.01 0.02
0.01 0.03
0.01 0.01