Subject: May 2023 Most Probable 24-Month Study

The operation of Lake Powell and Lake Mead in the May 2023 24-Month Study is pursuant to the December 2007 Record of Decision on Colorado River Interim 

Guidelines for Lower Basin Shortages and the Coordinated Operations of Lake Powell and Lake Mead (Interim Guidelines) and reflects the 2023 Annual Operating 

Plan (AOP). Pursuant to the Interim Guidelines, the August 2022 24-Month Study projections of the January 1, 2023, system storage and reservoir water surface 

elevations set the operational tier for the coordinated operation of Lake Powell and Lake Mead during 2023. 

The August 2022 24-Month Study projected the January 1, 2023 Lake Powell elevation to be less than 3,525 feet. Consistent with Section 6.D.1 of the Interim 

Guidelines, Lake Powell’s operation in Water Year (WY) 2023 is governed by the Lower Elevation Balancing Tier with an initial projected water year release 

volume of 7.00 million acre-feet (maf). Based on hydrologic conditions in April 2023, in which the most probable inflow into Lake Powell was projected to be 11.30 

maf (177 percent of average) during the 2023 April-July runoff period, Reclamation has determined that conditions are sufficient to release up to 9.50 maf from 

Lake Powell in WY 2023 consistent with Section 6.D.1 of the Interim Guidelines, but could be as low as 7.00 maf consistent with the Interim Guidelines and to 

protect Lake Powell from declining below elevation 3,525 feet at the end of December 2023. In addition, Reclamation has removed the operational neutrality of the 

0.480 maf that was retained in Lake Powell under the May 2022 action,1 such that balancing releases are based on the projected end of water year physical 

contents of Lake Powell and Lake Mead. Further, Lower Basin projections for Lake Mead take into consideration: updated water orders to reflect additional 

conservation efforts; new completed system conservation agreements under the Lower Colorado River Basin System Conservation and Efficiency Program (LC 

Conservation Program); and updated Lower Basin tributary inflow projections (reflecting current conditions) above Lake Mead, for the Bill Williams and for the Gila

River. 

Consistent with this operating approach and based on the most probable inflow forecast, the May 2023 24-Month Study projects a balancing release of 9.29 maf 

from Lake Powell in WY 2023; however, the actual release in WY 2023 will range between 7.00 and 9.50 maf and will depend on actual hydrology and reservoir 

conditions at Lake Powell and Lake Mead during the remainder of the water year. The projected release from Lake Powell in WY 2023 will be updated each month 

throughout the remainder of the water year. The modeling approach for 2024 and beyond will be consistent with the Interim Guidelines, based on projected 

physical elevations at Lake Powell and Lake Mead, and assume the 0.480 maf retained in Lake Powell under the May 2022 action was released as part of the WY 

2023 balancing release only if the release volume is 7.48 maf or greater. 

The 2022 Drought Response Operations Agreement (DROA) Plan2 for May 2022 through April 2023 has been amended to suspend 2022 DROA Plan releases for 

1 For more information: https://www.usbr.gov/uc/DocLibrary/Plans/20220503-2022DROA-GlenCanyonDamOperationsDecisionLetter-508-DOI.pdf.

2

 For more information: https://www.usbr.gov/uc/DocLibrary/Plans/20220429-2022DroughtResponseOperationsPlan-ApprovalMemo-508-DOI.pdf. 

To: All Annual Operating Plan Recipients

From: Noe Santos, P.E.

River Operations Manager

Boulder Canyon Operations Office

Interior Region 8: Lower Colorado Basin

 Email: nsantos@usbr.gov 

 

From: Alex Pivarnik

Supervisor, Water Management Group

Upper Colorado Operations Office

Interior Region 7: Upper Colorado Basin

 Email: apivarnik@usbr.gov 
the remainder of April 2023. The suspension of 2022 DROA Plan releases occurred on March 7, 2023. A total DROA release of approximately 463 thousand acrefeet (kaf) occurred under the 2022 DROA Plan. Reclamation will attempt to maximize DROA recovery in the Upper Initial Units in WY 2023 and through April 2024. 

Reclamation will provide monthly DROA accounting, including DROA releases and recovery, which can be found online at:

https://www.usbr.gov/dcp/DROSummarySheet.pdf. 

Reclamation continues to consult with the DROA Parties and to consult with the Lower Division States and others in accordance with the DROA on the 

implementation of the Drought Response Operations Plans and consideration of 2023 DROA Plan. 

Reclamation will continue to carefully monitor hydrologic and operational conditions and assess the need for additional responsive actions and/or changes to 

operations. Reclamation will continue to consult with the Basin States, Basin Tribes, Mexico, and other partners on Colorado River operations to consider and 

determine whether additional measures should be taken to further enhance the preservation of these benefits, as well as recovery protocols, including those of 

future protective measures for both Lakes Powell and Mead. 

The August 2022 24-Month Study projected the January 1, 2023 Lake Mead elevation, determined as if the 0.480 maf had been delivered to Lake Mead in WY

2022, to be below 1,050 feet and above 1,045 feet. Consistent with Section 2.D.1 of the Interim Guidelines, a Shortage Condition consistent with Section 2.D.1.b 

will govern the operation of Lake Mead for Calendar Year (CY) 2023. In addition, Section III.B of Exhibit 1 to the Lower Basin Drought Contingency Plan (DCP) 

Agreement will govern the operation of Lake Mead for CY 2023. Efforts to conserve additional water in Lake Mead under a 2021 Lower Basin Memorandum of 

Understanding (MOU) to facilitate near-term actions to maintain the water surface elevation of Lake Mead and the LC Conservation Program will also take place in 

CY 2023. 

Current runoff projections into Lake Powell are provided by the National Weather Service’s Colorado Basin River Forecast Center and are as follows. The 

observed unregulated inflow into Lake Powell for the month of April was 1.400 maf or 155 % of the 30-year average from 1991 to 2020. The May 2023 unregulated 

inflow forecast for Lake Powell is 4.00 maf or 193 % of the 30-year average. The 2023 April through July unregulated inflow forecast is 11.00 maf or 172 % of 

average.

In this study, the CY 2023 diversion for Metropolitan Water District of Southern California (MWD) is projected to be 0.832 maf. The CY 2023 diversion for the 

Central Arizona Project (CAP) is projected to be 0.920 maf. Consumptive use for Nevada above Hoover (SNWP Use) is projected to be 0.210 maf for CY 2023. 

Due to changing Lake Mead elevations, Hoover’s generator capacity is adjusted based on estimated effective capacity and plant availability. The estimated 

effective capacity is based on projected Lake Mead elevations. Unit capacity tests will be performed as the lake elevation changes. This study reflects these 

changes in the projections.

Hoover, Davis, and Parker Dam historical gross energy figures come from Power, Operations, and Maintenance reports provided by the Lower Colorado Region’s 

Power Office, Bureau of Reclamation, Boulder City, Nevada. Questions regarding these historical energy numbers can be directed to Cheri Woodward at (702) 

293-8101 or Rebecca Rogers at (702) 293-8091. 
Runoff and inflow projections into upper basin reservoirs are provided by the National Weather Service’s Colorado Basin River Forecast Center and are as follows:

Reservoir Observed Inflow (kaf) Apr Inflow Forecast (kaf)

Jan Feb Mar Apr %Avg May Jun Jul Apr-Jul %Avg

Lake Powell 361 270 573 1400 155% 4000 4200 1400 11000 172%

Fontenelle 32 28 29 75 89% 240 335 180 830 113%

Flaming Gorge 38 33 49 188 150% 415 490 207 1300 135%

Blue Mesa 24 19.9 25 78 99% 255 365 132 830 131%

Morrow Point 26 21 26 85 97% 280 385 140 890 129%

Crystal 28 23 29 97 99% 325 430 148 1000 130%

Taylor Park 4.4 3.6 3.2 7.1 81% 32 51 23 113 120%

Vallecito 5.4 4.7 6.6 36 153% 97 100 27 260 147%

Navajo 20 17.8 71 245 167% 435 275 55 1010 160%

Lemon 0.9 0.74 0.97 7.5 135% 29 33 6.5 76 158%

McPhee 4.1 3.2 9.1 147 242% 250 130 28 555 218%

Ridgway 3.9 3.2 4.9 10.5 107% 30 46 25 112 122%

Deerlodge 23 18.5 32 366 178% 1000 700 134 220 185%

Durango 10.3 8.4 11.2 61 123% 225 230 74 590 153%

The 2023 AOP is available online at:

https://www.usbr.gov/uc/water/rsvrs/ops/aop/AOP23.pdf. 

The Interim Guidelines are available online at:

https://www.usbr.gov/lc/region/programs/strategies/RecordofDecision.pdf. 

The Colorado River DCPs are available online at:

https://www.usbr.gov/dcp/finaldocs.html. 

The 2021 Lower Basin MOU is available online at: 

https://www.usbr.gov/lc/region/g4000/2021_MOU.pdf. 

The Upper Basin DROA is online at:

https://www.usbr.gov/dcp/droa.html. 

The Upper Basin Hydrology Summary is available online at:

https://www.usbr.gov/uc/water/crsp/studies/24Month_05_ucb.pdf. 

Information on the LC Conservation Program is available online at: 

https://www.usbr.gov/lc/LCBConservation.html. 
Most Probable Inflow*

May 2023 24-Month Study

Fontenelle Reservoir

OPERATION PLAN FOR COLORADO RIVER SYSTEM RESERVOIRS

Reservoir Elev

End of Month

(Ft)

Live

Storage

(1000 Ac-Ft)

Total

Release

(1000 Ac-Ft)

Regulated

Inflow

Date (1000 Ac-Ft)

Evap

Losses

(1000 Ac-Ft)

Power

Release

(1000 Ac-Ft)

Bypass

Release

(1000 Ac-Ft)

* May 2022 63 1 47 8 55 6479.96 158

H Jun 2022 241 2 82 0 82 6503.59 315

I Jul 2022 102 3 83 11 93 6504.34 321

S Aug 2022 56 2 67 1 68 6502.43 306

T Sep 2022 29 2 61 0 61 6498.08 274

WY 2022 744 15 617 67 685

O Oct 2022 40 1 22 39 61 6494.58 249

R Nov 2022 33 1 10 48 58 6490.90 224

I Dec 2022 28 1 56 2 58 6486.14 194

C Jan 2023 32 1 58 0 59 6481.53 167

A Feb 2023 28 0 10 43 53 6476.59 141

L Mar 2023 29 0 55 3 58 6470.02 113

* Apr 2023 75 1 61 0 61 6473.29 126

May 2023 240 1 101 49 151 6489.40 214

Jun 2023 335 2 104 164 268 6498.78 279

Jul 2023 180 3 103 54 157 6501.53 300

Aug 2023 70 2 92 0 92 6498.23 275

Sep 2023 45 2 60 0 60 6495.91 259

WY 2023 1135 15 732 403 1135

Oct 2023 45 1 61 0 61 6493.39 241

Nov 2023 44 1 63 0 63 6490.43 221

Dec 2023 32 1 68 0 68 6484.68 185

Jan 2024 31 1 68 0 68 6477.88 148

Feb 2024 29 0 63 0 63 6470.11 113

Mar 2024 51 0 64 0 64 6466.68 100

Apr 2024 77 1 34 18 53 6472.61 123

May 2024 166 1 92 0 92 6486.49 196

Jun 2024 301 2 103 111 214 6498.92 280

Jul 2024 146 3 103 22 125 6501.41 299

Aug 2024 59 2 98 0 98 6495.79 258

Sep 2024 39 2 88 0 88 6488.28 207

WY 2024 1020 14 906 151 1057

Oct 2024 45 1 55 0 55 6486.48 196

Nov 2024 42 1 55 0 55 6484.17 182

Dec 2024 32 1 58 0 58 6479.30 155

Jan 2025 31 0 58 0 58 6473.44 127

Feb 2025 29 0 53 0 53 6467.52 103

Mar 2025 51 0 51 0 51 6467.32 102

Apr 2025 77 1 37 9 46 6474.63 132

* Based on the Colorado River Basin Forecast Center's Most Probable Water Supply Forecast Model Run ID: 3224 Processed On: 5/9/2023 10:11:36AM 
Most Probable Inflow*

May 2023 24-Month Study

Flaming Gorge Reservoir

OPERATION PLAN FOR COLORADO RIVER SYSTEM RESERVOIRS

Reservoir Elev

End of Month

(Ft)

Live

Storage

(1000 Ac-Ft)

Total

Release

(1000 Ac-Ft)

Evap

Losses

Date (1000 Ac-Ft)

Bank

Storage

(1000 Ac-Ft)

Power

Release

(1000 Ac-Ft)

Unreg

Inflow

(1000 Ac-Ft)

Jensen

Flow

(1000 Ac-Ft)

Bypass

Release

(1000 Ac-Ft)

Reg

Inflow

(1000 Ac-Ft)

* May 2022 88 88 7 139 48 187 114 6015.77 2769 570

H Jun 2022 274 113 9 110 12 121 113 6015.25 2752 465

I Jul 2022 125 110 11 79 0 79 106 6016.09 2780 137

S Aug 2022 58 70 11 105 0 105 104 6014.73 2735 124

T Sep 2022 32 63 9 112 0 112 102 6013.01 2680 125

WY 2022 897 837 70 927 60 987 2138

O Oct 2022 41 65 6 111 0 111 100 6011.45 2630 142

R Nov 2022 40 63 3 102 0 102 98 6010.19 2590 132

I Dec 2022 26 57 2 107 0 107 96 6008.59 2540 138

C Jan 2023 38 65 2 108 0 108 95 6007.19 2497 143

A Feb 2023 33 58 2 98 0 98 93 6005.89 2457 135

L Mar 2023 49 77 3 61 5 66 93 6006.15 2465 119

* Apr 2023 188 181 4 48 0 48 98 6010.17 2589 407

May 2023 415 326 7 51 0 51 109 6018.13 2847 1051

Jun 2023 490 423 9 157 0 157 118 6025.30 3093 857

Jul 2023 207 184 13 85 0 85 122 6027.64 3177 219

Aug 2023 80 102 12 93 0 93 122 6027.56 3174 123

Sep 2023 50 65 10 101 0 101 120 6026.31 3129 121

WY 2023 1658 1665 72 1121 5 1126 3587

Oct 2023 52 68 7 60 0 60 120 6026.36 3131 86

Nov 2023 53 72 3 57 0 57 120 6026.69 3143 92

Dec 2023 34 70 2 90 0 90 120 6026.08 3121 115

Jan 2024 42 79 2 90 0 90 119 6025.72 3108 115

Feb 2024 43 77 2 85 0 85 119 6025.47 3099 110

Mar 2024 85 98 3 61 0 61 120 6026.38 3132 135

Apr 2024 111 87 5 60 0 60 121 6026.99 3153 263

May 2024 239 165 7 227 0 227 118 6025.11 3087 740

Jun 2024 389 302 10 63 0 63 127 6031.09 3307 430

Jul 2024 161 140 14 72 0 72 129 6032.41 3359 132

Aug 2024 66 105 13 103 0 103 129 6032.14 3348 122

Sep 2024 43 92 12 110 0 110 127 6031.42 3320 123

WY 2024 1318 1355 79 1078 0 1078 2463

Oct 2024 52 62 7 76 0 76 127 6030.89 3299 102

Nov 2024 50 63 4 80 0 80 126 6030.39 3280 110

Dec 2024 34 60 2 124 0 124 123 6028.76 3218 149

Jan 2025 42 69 2 124 0 124 121 6027.28 3164 149

Feb 2025 43 67 2 112 0 112 119 6026.02 3119 137

Mar 2025 85 85 3 61 0 61 120 6026.58 3139 135

Apr 2025 111 80 5 60 0 60 121 6027.02 3155 263

* Based on the Colorado River Basin Forecast Center's Most Probable Water Supply Forecast Model Run ID: 3224 Processed On: 5/9/2023 10:11:36AM 
Most Probable Inflow*

May 2023 24-Month Study

Taylor Park Reservoir

OPERATION PLAN FOR COLORADO RIVER SYSTEM RESERVOIRS

Reservoir Elev

End of Month

(Ft)

Live

Storage

(1000 Ac-Ft)

Total

Release

(1000 Ac-Ft)

Regulated

Inflow

Date (1000 Ac-Ft)

* May 2022 27 12 9312.55 74

H Jun 2022 26 19 9316.61 81

I Jul 2022 11 15 9314.18 77

S Aug 2022 8 14 9310.35 70

T Sep 2022 5 8 9308.87 68

WY 2022 110 100

O Oct 2022 6 6 9308.80 68

R Nov 2022 4 5 9308.13 67

I Dec 2022 5 5 9307.68 66

C Jan 2023 4 5 9307.08 65

A Feb 2023 4 5 9306.26 64

L Mar 2023 4 5 9305.50 63

* Apr 2023 7 9 9304.30 61

May 2023 33 18 9313.88 76

Jun 2023 51 25 9327.98 102

Jul 2023 22 25 9326.67 100

Aug 2023 11 22 9321.14 89

Sep 2023 7 18 9315.03 78

WY 2023 158 148

Oct 2023 7 13 9311.24 72

Nov 2023 5 6 9310.65 71

Dec 2023 4 6 9309.30 69

Jan 2024 5 6 9308.57 68

Feb 2024 4 6 9307.56 66

Mar 2024 5 6 9306.81 65

Apr 2024 9 12 9304.80 62

May 2024 26 18 9310.03 70

Jun 2024 40 27 9317.77 83

Jul 2024 15 27 9310.65 71

Aug 2024 8 24 9299.84 55

Sep 2024 7 18 9291.00 44

WY 2024 135 169

Oct 2024 7 9 9289.20 42

Nov 2024 5 6 9288.33 41

Dec 2024 4 6 9286.28 39

Jan 2025 5 6 9285.14 38

Feb 2025 4 6 9283.57 36

Mar 2025 5 6 9282.36 35

Apr 2025 9 9 9282.36 35

* Based on the Colorado River Basin Forecast Center's Most Probable Water Supply Forecast Model Run ID: 3224 Processed On: 5/9/2023 10:11:36AM 
Most Probable Inflow*

May 2023 24-Month Study

Blue Mesa Reservoir

OPERATION PLAN FOR COLORADO RIVER SYSTEM RESERVOIRS

Reservoir Elev

End of Month

(Ft)

Live

Storage

(1000 Ac-Ft)

Total

Release

(1000 Ac-Ft)

Regulated

Inflow

Date (1000 Ac-Ft)

Evap

Losses

(1000 Ac-Ft)

Power

Release

(1000 Ac-Ft)

Bypass

Release

(1000 Ac-Ft)

UnReg

Inflow

(1000 Ac-Ft)

* May 2022 177 162 1 79 0 79 7454.56 335

H Jun 2022 133 126 1 69 0 69 7463.76 391

I Jul 2022 59 63 1 84 0 84 7460.15 368

S Aug 2022 57 64 1 89 0 89 7455.69 341

T Sep 2022 31 33 1 55 28 82 7446.72 292

WY 2022 661 652 6 566 28 595

O Oct 2022 32 32 0 0 58 58 7441.74 266

R Nov 2022 26 27 0 1 10 11 7444.87 282

I Dec 2022 24 25 0 6 10 17 7446.44 290

C Jan 2023 24 25 0 20 0 20 7447.43 295

A Feb 2023 20 21 0 20 0 20 7447.61 296

L Mar 2023 25 26 0 19 0 19 7448.79 303

* Apr 2023 77 79 1 23 0 23 7458.56 358

May 2023 255 240 1 98 0 98 7479.64 499

Jun 2023 365 339 1 84 0 84 7511.11 753

Jul 2023 132 135 2 104 0 104 7514.36 782

Aug 2023 64 75 1 107 0 107 7510.58 749

Sep 2023 38 49 1 27 74 101 7504.42 695

WY 2023 1083 1073 8 509 153 661

Oct 2023 36 42 1 68 0 68 7501.34 669

Nov 2023 32 33 0 51 0 51 7499.13 651

Dec 2023 26 28 0 92 0 92 7491.13 587

Jan 2024 25 26 0 43 0 43 7488.92 569

Feb 2024 23 25 0 40 0 40 7486.88 554

Mar 2024 38 39 0 46 0 46 7485.93 546

Apr 2024 78 81 1 47 0 47 7490.27 580

May 2024 204 196 1 80 0 80 7504.32 694

Jun 2024 251 238 1 132 0 132 7516.20 799

Jul 2024 86 98 2 108 0 108 7514.90 787

Aug 2024 55 71 1 112 0 112 7510.15 745

Sep 2024 35 46 1 103 0 103 7503.38 686

WY 2024 889 923 9 923 0 923

Oct 2024 36 38 1 87 0 87 7497.41 637

Nov 2024 31 32 0 48 0 48 7495.35 620

Dec 2024 26 28 0 65 0 65 7490.73 583

Jan 2025 25 26 0 49 0 49 7487.73 560

Feb 2025 23 25 0 44 0 44 7485.15 540

Mar 2025 38 39 0 39 0 39 7485.05 540

Apr 2025 78 78 1 43 0 43 7489.57 574

* Based on the Colorado River Basin Forecast Center's Most Probable Water Supply Forecast Model Run ID: 3224 Processed On: 5/9/2023 10:11:36AM 
Most Probable Inflow*

May 2023 24-Month Study

Morrow Point Reservoir

OPERATION PLAN FOR COLORADO RIVER SYSTEM RESERVOIRS

Reservoir Elev

End of Month

(Ft)

Total

Release

(1000 Ac-Ft)

Blue Mesa

Release

Date (1000 Ac-Ft)

Side

Inflow

(1000 Ac-Ft)

Power

Release

(1000 Ac-Ft)

Bypass

Release

(1000 Ac-Ft)

Unreg

Inflow

(1000 Ac-Ft)

Live

Storage

(1000 Ac-Ft)

Total

Inflow

(1000 Ac-Ft)

* May 2022 186 79 9 88 89 0 89 7152.08 111

H Jun 2022 134 69 1 70 71 0 71 7150.86 110

I Jul 2022 60 84 1 85 84 0 84 7152.31 111

S Aug 2022 58 89 1 90 90 0 90 7152.25 111

T Sep 2022 31 82 1 83 78 0 78 7157.81 115

WY 2022 685 595 24 619 614 0 614

O Oct 2022 33 58 1 59 60 0 60 7156.10 114

R Nov 2022 27 11 1 12 21 0 21 7143.98 104

I Dec 2022 26 17 2 18 20 0 20 7141.82 103

C Jan 2023 26 20 2 21 20 0 20 7144.03 105

A Feb 2023 21 20 1 21 18 0 18 7148.07 108

L Mar 2023 26 19 2 21 19 0 19 7149.91 109

* Apr 2023 85 23 8 31 30 0 30 7151.54 110

May 2023 280 98 25 123 121 0 121 7153.73 112

Jun 2023 385 84 20 104 104 0 104 7153.72 112

Jul 2023 140 104 8 112 112 0 112 7153.73 112

Aug 2023 67 107 3 110 110 0 110 7153.73 112

Sep 2023 40 101 2 103 103 0 103 7153.73 112

WY 2023 1157 661 74 735 738 0 738

Oct 2023 37 68 1 69 69 0 69 7153.73 112

Nov 2023 33 51 1 52 52 0 52 7153.73 112

Dec 2023 27 92 1 93 93 0 93 7153.73 112

Jan 2024 26 43 1 44 44 0 44 7153.73 112

Feb 2024 25 40 2 42 42 0 42 7153.73 112

Mar 2024 40 46 2 48 48 0 48 7153.73 112

Apr 2024 89 47 11 58 58 0 58 7153.73 112

May 2024 226 80 22 102 102 0 102 7153.73 112

Jun 2024 265 132 14 146 146 0 146 7153.72 112

Jul 2024 90 108 4 112 112 0 112 7153.73 112

Aug 2024 56 112 1 113 113 0 113 7153.73 112

Sep 2024 36 103 1 104 104 0 104 7153.73 112

WY 2024 950 923 61 984 983 0 983

Oct 2024 37 87 1 88 88 0 88 7153.73 112

Nov 2024 32 48 1 49 49 0 49 7153.73 112

Dec 2024 27 65 1 66 66 0 66 7153.73 112

Jan 2025 26 49 1 50 50 0 50 7153.73 112

Feb 2025 25 44 2 46 46 0 46 7153.73 112

Mar 2025 40 39 2 41 41 0 41 7153.73 112

Apr 2025 89 43 11 54 53 0 53 7153.73 112

* Based on the Colorado River Basin Forecast Center's Most Probable Water Supply Forecast Model Run ID: 3224 Processed On: 5/9/2023 10:11:36AM 
Most Probable Inflow*

May 2023 24-Month Study

Crystal Reservoir

OPERATION PLAN FOR COLORADO RIVER SYSTEM RESERVOIRS

Reservoir Elev

End of Month

(Ft)

Live

Storage

(1000 Ac-Ft)

Total

Release

(1000 Ac-Ft)

Morrow

Release

Date (1000 Ac-Ft)

Total

Inflow

(1000 Ac-Ft)

Bypass

Release

(1000 Ac-Ft)

Below Tunnel

Flow

(1000 Ac-Ft)

Unreg

Inflow

(1000 Ac-Ft)

Tunnel

Flow

(1000 Ac-Ft)

Power

Release

(1000 Ac-Ft)

Side

Inflow

(1000 Ac-Ft)

* May 2022 203 89 17 105 92 13 106 6751.40 16 59 48

H Jun 2022 145 71 10 82 80 2 81 6752.67 17 62 21

I Jul 2022 64 84 5 89 90 0 90 6747.68 15 65 28

S Aug 2022 62 90 4 94 92 0 93 6751.52 17 66 31

T Sep 2022 33 78 2 80 69 12 80 6750.17 16 62 22

WY 2022 755 614 70 684 622 62 684 393 295

O Oct 2022 36 60 3 63 53 10 63 6751.29 16 41 21

R Nov 2022 29 21 2 23 21 2 23 6752.92 17 0 21

I Dec 2022 28 20 2 22 22 0 22 6751.64 17 2 21

C Jan 2023 28 20 2 22 22 0 22 6751.37 16 2 21

A Feb 2023 23 18 2 20 4 16 20 6751.71 17 1 19

L Mar 2023 29 19 2 22 0 22 22 6751.16 16 2 21

* Apr 2023 97 30 12 42 20 21 41 6752.29 17 19 22

May 2023 325 121 45 166 134 32 166 6753.04 17 62 104

Jun 2023 430 104 45 149 130 19 149 6753.03 17 61 88

Jul 2023 148 112 8 120 120 0 120 6753.04 17 65 55

Aug 2023 71 110 4 114 114 0 114 6753.04 17 65 49

Sep 2023 44 103 4 107 107 0 107 6753.04 17 55 52

WY 2023 1289 738 132 870 747 122 869 375 494

Oct 2023 43 69 6 75 52 22 75 6753.04 17 55 20

Nov 2023 38 52 5 57 57 0 57 6753.04 17 0 57

Dec 2023 32 93 5 98 98 0 98 6753.04 17 0 98

Jan 2024 31 44 5 49 49 0 49 6753.04 17 0 49

Feb 2024 29 42 4 46 46 0 46 6753.04 17 0 46

Mar 2024 46 48 6 54 54 0 54 6753.04 17 5 49

Apr 2024 100 58 11 69 69 0 69 6753.04 17 42 27

May 2024 251 102 25 127 127 0 127 6753.04 17 62 65

Jun 2024 293 146 28 174 130 44 174 6753.03 17 61 113

Jul 2024 98 112 8 120 120 0 120 6753.04 17 65 55

Aug 2024 63 113 7 120 120 0 120 6753.04 17 65 55

Sep 2024 42 104 6 110 110 0 110 6753.04 17 55 55

WY 2024 1066 983 116 1099 1032 67 1099 410 689

Oct 2024 43 88 6 94 56 38 94 6753.04 17 55 39

Nov 2024 37 49 5 54 54 0 54 6753.04 17 0 54

Dec 2024 32 66 5 71 71 0 71 6753.04 17 0 71

Jan 2025 31 50 5 55 55 0 55 6753.04 17 0 55

Feb 2025 29 46 4 50 50 0 50 6753.04 17 0 50

Mar 2025 46 41 6 47 47 0 47 6753.04 17 5 42

Apr 2025 100 53 11 64 64 0 64 6753.04 17 42 22

* Based on the Colorado River Basin Forecast Center's Most Probable Water Supply Forecast Model Run ID: 3224 Processed On: 5/9/2023 10:11:36AM 
Most Probable Inflow*

May 2023 24-Month Study

Vallecito Reservoir

OPERATION PLAN FOR COLORADO RIVER SYSTEM RESERVOIRS

Reservoir Elev

End of Month

(Ft)

Live

Storage

(1000 Ac-Ft)

Total

Release

(1000 Ac-Ft)

Regulated

Inflow

Date (1000 Ac-Ft)

* May 2022 53 33 7652.10 92

H Jun 2022 26 34 7648.50 83

I Jul 2022 19 32 7642.57 70

S Aug 2022 18 28 7637.64 59

T Sep 2022 12 26 7630.15 45

WY 2022 185 160

O Oct 2022 14 3 7635.84 56

R Nov 2022 7 0 7639.00 62

I Dec 2022 5 0 7641.15 67

C Jan 2023 5 0 7643.44 72

A Feb 2023 5 2 7644.74 75

L Mar 2023 7 36 7630.44 46

* Apr 2023 36 45 7625.05 36

May 2023 97 57 7645.49 77

Jun 2023 100 53 7664.08 123

Jul 2023 27 42 7658.34 108

Aug 2023 16 38 7649.39 86

Sep 2023 14 30 7642.44 70

WY 2023 333 305

Oct 2023 13 17 7640.41 65

Nov 2023 9 2 7643.66 72

Dec 2023 7 2 7645.91 78

Jan 2024 6 2 7647.67 82

Feb 2024 5 2 7649.01 85

Mar 2024 10 2 7652.31 93

Apr 2024 23 2 7660.52 114

May 2024 68 58 7664.08 123

Jun 2024 62 62 7663.74 122

Jul 2024 21 41 7655.67 101

Aug 2024 15 38 7646.11 78

Sep 2024 16 29 7639.98 64

WY 2024 255 257

Oct 2024 13 16 7638.25 61

Nov 2024 9 2 7641.60 68

Dec 2024 7 2 7643.91 73

Jan 2025 6 2 7645.71 77

Feb 2025 5 2 7647.11 80

Mar 2025 10 2 7650.46 88

Apr 2025 23 2 7658.80 109

* Based on the Colorado River Basin Forecast Center's Most Probable Water Supply Forecast Model Run ID: 3224 Processed On: 5/9/2023 10:11:36AM 
Most Probable Inflow*

May 2023 24-Month Study

Navajo Reservoir

OPERATION PLAN FOR COLORADO RIVER SYSTEM RESERVOIRS

Reservoir Elev

End of Month

(Ft)

Live

Storage

(1000 Ac-Ft)

Total

Release

(1000 Ac-Ft)

Azotea

Tunnel Div

Date (1000 Ac-Ft)

Reg

Inflow

(1000 Ac-Ft)

Evap

Losses

(1000 Ac-Ft)

NIIP

Diversion

(1000 Ac-Ft)

Mod Unreg

Inflow

(1000 Ac-Ft)

Farmington

Flow

(1000 Ac-Ft)

* May 2022 167 30 114 3 38 18 6029.39 954 104

H Jun 2022 47 7 50 3 37 24 6027.89 939 61

I Jul 2022 44 5 54 3 39 35 6025.41 916 55

S Aug 2022 53 5 56 3 38 30 6023.95 902 49

T Sep 2022 22 1 35 2 23 40 6020.65 872 56

WY 2022 574 66 484 20 200 296 595

O Oct 2022 44 2 32 1 5 33 6019.84 865 51

R Nov 2022 23 0 16 1 0 19 6019.52 862 37

I Dec 2022 17 0 13 0 0 22 6018.45 852 37

C Jan 2023 20 0 15 0 0 20 6017.85 847 34

A Feb 2023 18 0 15 1 1 17 6017.38 843 31

L Mar 2023 71 0 98 1 3 18 6025.86 920 45

* Apr 2023 245 24 235 2 8 21 6045.83 1124 109

May 2023 435 54 340 3 33 140 6059.60 1287 365

Jun 2023 275 38 190 4 48 176 6056.54 1249 406

Jul 2023 55 4 65 4 52 18 6055.75 1240 92

Aug 2023 30 2 50 3 44 22 6054.16 1220 58

Sep 2023 26 1 41 3 24 20 6053.69 1215 48

WY 2023 1260 126 1110 24 218 525 1313

Oct 2023 35 2 38 2 9 19 6054.35 1223 42

Nov 2023 28 1 20 1 0 18 6054.44 1224 36

Dec 2023 24 0 19 1 0 18 6054.41 1223 33

Jan 2024 22 0 18 1 0 22 6054.05 1219 35

Feb 2024 29 1 25 1 0 20 6054.36 1223 32

Mar 2024 92 10 74 2 6 22 6058.03 1268 45

Apr 2024 147 18 107 2 21 21 6062.95 1330 72

May 2024 251 34 207 4 36 235 6057.69 1264 370

Jun 2024 187 25 163 4 52 157 6053.58 1213 301

Jul 2024 33 2 51 4 55 22 6051.04 1183 73

Aug 2024 24 1 45 3 46 27 6048.36 1152 56

Sep 2024 31 2 43 2 25 21 6047.85 1146 47

WY 2024 903 96 809 26 250 601 1141

Oct 2024 35 2 37 2 9 22 6048.30 1152 45

Nov 2024 30 1 22 1 0 21 6048.32 1152 39

Dec 2024 24 0 19 1 0 22 6048.02 1148 37

Jan 2025 22 0 18 1 0 22 6047.63 1144 35

Feb 2025 29 1 25 1 0 19 6048.02 1148 31

Mar 2025 92 10 74 1 5 22 6051.95 1194 45

Apr 2025 147 18 107 2 21 21 6057.19 1257 72

* Based on the Colorado River Basin Forecast Center's Most Probable Water Supply Forecast Model Run ID: 3224 Processed On: 5/9/2023 10:11:36AM 
Most Probable Inflow*

May 2023 24-Month Study

Lake Powell

OPERATION PLAN FOR COLORADO RIVER SYSTEM RESERVOIRS

Reservoir Elev

End of Month

(Ft)

Bank

Storage

(1000 Ac-Ft)

Total

Release

(1000 Ac-Ft)

Regulated

Inflow

Date (1000 Ac-Ft)

Evap

Losses

(1000 Ac-Ft)

Bypass

Release

(1000 Ac-Ft)

Lees

Ferry Gage

(1000 Ac-Ft)

Unreg

Inflow

(1000 Ac-Ft)

EOM

Storage

(1000 Ac-Ft)

PowerPlant

Release

(1000 Ac-Ft)

* May 2022 1382 1212 14 598 0 598 3531.69 4561 6346 599

H Jun 2022 1284 1198 25 598 0 598 3539.81 4604 6878 595

I Jul 2022 491 463 28 672 0 672 3536.20 4551 6212 672

S Aug 2022 368 444 27 713 0 713 3531.69 4529 5938 722

T Sep 2022 245 420 24 547 0 547 3529.33 4517 5797 562

WY 2022 6084 6107 203 6999 0 6999 7066

O Oct 2022 437 535 17 480 0 480 3529.92 4520 5832 494

R Nov 2022 349 394 17 498 0 498 3528.02 4511 5720 507

I Dec 2022 281 358 13 550 0 550 3524.75 4496 5531 560

C Jan 2023 361 424 4 500 0 501 3523.45 4490 5456 510

A Feb 2023 270 337 4 480 0 480 3521.04 4479 5320 493

L Mar 2023 573 552 6 486 0 486 3522.02 4484 5375 500

* Apr 2023 1399 1103 10 819 90 909 3524.99 4497 5544 931

May 2023 4000 3270 15 1088 0 1088 3556.64 4658 7551 1109

Jun 2023 4200 3573 31 1064 0 1064 3586.77 4841 9846 1081

Jul 2023 1400 1270 41 1150 0 1150 3587.64 4847 9918 1165

Aug 2023 500 594 41 1175 0 1175 3580.60 4801 9342 1189

Sep 2023 400 533 36 909 0 909 3575.77 4771 8960 925

WY 2023 14170 12940 234 9200 90 9291 9465

Oct 2023 417 451 25 480 0 480 3575.13 4767 8911 496

Nov 2023 490 504 24 500 0 500 3574.89 4765 8892 505

Dec 2023 361 478 19 600 0 600 3573.20 4755 8762 603

Jan 2024 350 416 6 723 0 723 3569.40 4731 8473 727

Feb 2024 397 448 6 639 0 639 3566.95 4717 8290 650

Mar 2024 614 544 10 675 0 675 3565.17 4706 8159 689

Apr 2024 920 751 16 601 0 601 3566.86 4716 8284 618

May 2024 2060 1978 20 599 0 599 3583.07 4817 9542 620

Jun 2024 2423 2025 36 628 0 628 3597.88 4918 10802 645

Jul 2024 711 690 45 709 0 709 3597.22 4913 10743 724

Aug 2024 371 515 45 758 0 758 3594.19 4892 10476 772

Sep 2024 316 468 41 568 0 568 3592.68 4881 10346 584

WY 2024 9430 9267 291 7480 0 7480 7633

Oct 2024 417 489 28 643 0 643 3590.72 4868 10177 659

Nov 2024 450 489 27 642 0 642 3588.75 4855 10011 647

Dec 2024 361 487 21 715 0 715 3585.98 4836 9780 718

Jan 2025 350 456 6 857 0 857 3581.35 4806 9403 861

Feb 2025 397 478 6 749 9 758 3578.03 4785 9138 769

Mar 2025 614 537 11 801 0 801 3574.78 4764 8883 815

Apr 2025 920 746 17 713 0 713 3574.97 4766 8898 730

* Based on the Colorado River Basin Forecast Center's Most Probable Water Supply Forecast Model Run ID: 3224 Processed On: 5/9/2023 10:11:36AM 
Most Probable Inflow*

May 2023 24-Month Study

Hoover Dam - Lake Mead

OPERATION PLAN FOR COLORADO RIVER SYSTEM RESERVOIRS

Reservoir Elev

End of Month

(Ft)

Bank

Storage

(1000 Ac-Ft)

SNWP

Use

(1000 Ac-Ft)

Side Inflow

Glen to Hoover

Date (1000 Ac-Ft)

Evap

Losses

(1000 Ac-Ft)

Total

Release

(1000 Ac-Ft)

Total

Release

(1000 CFS)

Glen

Release

(1000 Ac-Ft)

EOM

Storage

(1000 Ac-Ft)

Downstream

Requirements

(1000 Ac-Ft)

* May 2022 598 8 40 1083 17.6 25 1075 489 1047.69 7517

H Jun 2022 598 16 47 889 14.9 29 877 467 1043.02 7187

I Jul 2022 672 70 45 822 13.4 31 814 458 1040.92 7041

S Aug 2022 713 183 48 573 9.3 25 567 473 1044.28 7275

T Sep 2022 547 117 48 539 9.1 21 545 476 1045.03 7328

WY 2022 6999 787 463 8899 222 8888

O Oct 2022 480 94 46 418 6.8 16 434 482 1046.28 7417

R Nov 2022 498 18 40 713 12.0 8 714 467 1043.02 7187

I Dec 2022 550 63 32 438 7.1 8 439 475 1044.82 7313

C Jan 2023 501 103 22 412 6.7 7 413 485 1046.97 7466

A Feb 2023 480 46 21 494 8.9 8 493 485 1047.02 7469

L Mar 2023 486 226 23 754 12.3 10 749 481 1046.03 7399

* Apr 2023 909 243 31 831 14.0 12 830 498 1049.69 7661

May 2023 1088 181 40 965 15.7 26 965 512 1052.77 7884

Jun 2023 1064 90 49 866 14.5 32 866 525 1055.41 8079

Jul 2023 1150 55 48 818 13.3 32 818 544 1059.27 8367

Aug 2023 1175 86 53 762 12.4 31 762 569 1064.35 8757

Sep 2023 909 72 53 688 11.6 23 688 582 1066.97 8960

WY 2023 9291 1277 457 8157 215 8168

Oct 2023 480 77 50 459 7.5 15 459 584 1067.36 8991

Nov 2023 500 63 44 606 10.2 7 606 579 1066.22 8902

Dec 2023 600 72 36 538 8.7 7 538 584 1067.32 8988

Jan 2024 723 75 25 591 9.6 10 591 595 1069.38 9150

Feb 2024 639 71 23 563 9.8 7 563 602 1070.76 9260

Mar 2024 675 97 25 908 14.8 13 908 591 1068.70 9096

Apr 2024 601 60 34 1033 17.4 14 1033 566 1063.64 8701

May 2024 599 37 42 1014 16.5 18 1014 539 1058.23 8290

Jun 2024 628 22 50 898 15.1 26 898 519 1054.16 7986

Jul 2024 709 55 47 789 12.8 29 789 513 1052.85 7890

Aug 2024 758 86 51 751 12.2 31 751 514 1052.99 7900

Sep 2024 568 72 50 673 11.3 27 673 507 1051.57 7797

WY 2024 7480 786 477 8823 205 8823

Oct 2024 643 77 47 486 7.9 22 486 517 1053.69 7952

Nov 2024 642 63 42 592 9.9 12 592 521 1054.45 8008

Dec 2024 715 72 34 524 8.5 8 524 534 1057.25 8216

Jan 2025 857 75 24 587 9.5 12 587 553 1061.09 8506

Feb 2025 758 71 22 558 10.1 9 558 567 1064.02 8731

Mar 2025 801 97 25 903 14.7 16 903 565 1063.45 8687

Apr 2025 713 60 33 1029 17.3 18 1029 546 1059.68 8399

* Based on the Colorado River Basin Forecast Center's Most Probable Water Supply Forecast Model Run ID: 3224 Processed On: 5/9/2023 10:11:36AM 
Most Probable Inflow*

May 2023 24-Month Study

Davis Dam - Lake Mohave

OPERATION PLAN FOR COLORADO RIVER SYSTEM RESERVOIRS

Reservoir Elev

End of Month

(Ft)

EOM

Storage

(1000 Ac-Ft)

Total

Release

(1000 Ac-Ft)

Side

Inflow

Date (1000 Ac-Ft)

Evap

Losses

(1000 Ac-Ft)

Power

Release

(1000 Ac-Ft)

Spill

Release

(1000 Ac-Ft)

Hoover

Release

(1000 Ac-Ft)

Total

Release

(1000 CFS)

* May 2022 1083 -20 14 1041 0 1041 16.9 643.35 1708

H Jun 2022 889 -30 14 842 0 842 14.1 643.47 1712

I Jul 2022 822 -26 12 770 0 770 12.5 643.97 1725

S Aug 2022 573 -13 16 575 0 575 9.3 642.87 1695

T Sep 2022 539 -6 16 617 0 617 10.4 639.17 1595

WY 2022 8899 -222 151 8495 0 8495

O Oct 2022 418 -2 14 540 0 542 8.8 633.78 1454

R Nov 2022 713 -15 13 516 0 516 8.7 640.22 1623

I Dec 2022 438 4 13 436 0 436 7.1 639.97 1617

C Jan 2023 412 2 9 347 0 347 5.6 642.12 1675

A Feb 2023 494 -18 8 429 0 444 8.0 643.00 1699

L Mar 2023 754 -6 10 705 0 705 11.5 644.17 1731

* Apr 2023 831 -10 13 844 0 844 14.2 642.84 1694

May 2023 965 -13 14 933 0 933 15.2 643.00 1699

Jun 2023 866 -21 14 831 0 831 14.0 643.00 1699

Jul 2023 818 -21 12 811 0 811 13.2 642.00 1671

Aug 2023 762 -17 15 730 0 730 11.9 642.00 1671

Sep 2023 688 -6 16 719 0 719 12.1 640.01 1617

WY 2023 8157 -124 151 7841 0 7859

Oct 2023 459 -11 14 617 0 617 10.0 633.00 1434

Nov 2023 606 -16 13 526 0 526 8.8 635.00 1486

Dec 2023 538 -2 13 405 0 405 6.6 639.51 1604

Jan 2024 591 -11 9 509 0 509 8.3 641.80 1666

Feb 2024 563 -13 8 542 0 542 9.4 641.80 1666

Mar 2024 908 -10 10 853 0 853 13.9 643.05 1700

Apr 2024 1033 -14 13 1009 0 1009 17.0 643.00 1699

May 2024 1014 -13 14 987 0 987 16.0 643.00 1699

Jun 2024 898 -21 14 863 0 863 14.5 643.00 1699

Jul 2024 789 -21 12 783 0 783 12.7 642.00 1671

Aug 2024 751 -17 15 719 0 719 11.7 642.00 1671

Sep 2024 673 -6 16 705 0 705 11.8 640.01 1617

WY 2024 8823 -154 151 8518 0 8518

Oct 2024 486 -11 14 644 0 644 10.5 633.00 1434

Nov 2024 592 -16 13 512 0 512 8.6 635.00 1486

Dec 2024 524 -2 13 391 0 391 6.4 639.51 1604

Jan 2025 587 -11 9 505 0 505 8.2 641.80 1666

Feb 2025 558 -13 8 538 0 538 9.7 641.80 1666

Mar 2025 903 -10 10 849 0 849 13.8 643.05 1700

Apr 2025 1029 -14 13 1005 0 1005 16.9 643.00 1699

* Based on the Colorado River Basin Forecast Center's Most Probable Water Supply Forecast Model Run ID: 3224 Processed On: 5/9/2023 10:11:36AM 
Most Probable Inflow*

May 2023 24-Month Study

Parker Dam - Lake Havasu

OPERATION PLAN FOR COLORADO RIVER SYSTEM RESERVOIRS

Reservoir Elev

End of Month

(Ft)

EOM

Storage

(1000 Ac-Ft)

Total

Release

(1000 Ac-Ft)

Evap

Losses

Date (1000 Ac-Ft)

CAP

Diversion

(1000 Ac-Ft)

MWD

Diversion

(1000 Ac-Ft)

Flow To

Mexico

(1000 CFS)

Davis

Release

(1000 Ac-Ft)

Flow To

Mexico

(1000 Ac-Ft)

Total

Release

(1000 CFS)

Side

Inflow

(1000 Ac-Ft)

* May 2022 1041 8 13 741 12.0 106 150 448.68 593 145 2.4

H Jun 2022 842 18 15 679 11.4 103 60 448.30 586 154 2.6

I Jul 2022 770 31 17 639 10.4 106 19 448.84 596 150 2.4

S Aug 2022 575 40 17 482 7.8 106 16 448.16 583 120 2.0

T Sep 2022 617 15 15 458 7.7 103 52 447.96 579 108 1.8

WY 2022 8495 176 140 6231 1117 1112 1499

O Oct 2022 542 26 12 393 6.4 106 66 447.14 564 67 1.1

R Nov 2022 516 1 9 336 5.6 103 67 447.09 563 89 1.5

I Dec 2022 436 14 7 277 4.5 101 63 447.06 562 87 1.4

C Jan 2023 347 16 6 261 4.2 54 40 447.14 564 125 2.0

A Feb 2023 444 1 8 370 6.7 16 40 447.47 570 130 2.3

L Mar 2023 705 41 9 553 9.0 70 91 448.31 586 168 2.7

* Apr 2023 844 52 11 669 11.2 49 169 447.68 574 153 2.6

May 2023 933 20 13 680 11.1 68 175 448.00 580 127 2.1

Jun 2023 831 24 15 693 11.6 67 68 448.00 580 130 2.2

Jul 2023 811 17 17 708 11.5 71 21 448.00 580 130 2.1

Aug 2023 730 19 17 625 10.2 85 20 447.50 571 103 1.7

Sep 2023 719 12 15 537 9.0 82 86 447.50 570 96 1.6

WY 2023 7859 242 139 6102 871 908 1404

Oct 2023 617 21 12 466 7.6 85 67 447.50 571 68 1.1

Nov 2023 526 14 9 365 6.1 91 70 447.50 570 84 1.4

Dec 2023 405 17 7 263 4.3 94 73 446.50 552 84 1.4

Jan 2024 509 7 6 313 5.1 90 101 446.50 552 138 2.2

Feb 2024 542 4 8 411 7.1 12 109 446.50 552 124 2.2

Mar 2024 853 2 9 608 9.9 102 123 446.70 555 147 2.4

Apr 2024 1009 7 11 727 12.2 93 136 448.70 593 147 2.5

May 2024 987 4 13 734 11.9 89 143 448.70 593 110 1.8

Jun 2024 863 10 16 714 12.0 86 45 448.70 593 116 2.0

Jul 2024 783 17 17 686 11.2 89 10 448.00 580 123 2.0

Aug 2024 719 19 17 621 10.1 89 10 447.50 571 102 1.7

Sep 2024 705 12 15 533 9.0 86 72 447.50 570 99 1.7

WY 2024 8518 134 139 6439 1006 960 1342

Oct 2024 644 21 12 482 7.8 89 74 447.50 571 89 1.4

Nov 2024 512 14 9 375 6.3 86 49 447.50 570 115 1.9

Dec 2024 391 17 7 270 4.4 89 57 446.50 552 110 1.8

Jan 2025 505 7 6 313 5.1 86 101 446.50 552 138 2.2

Feb 2025 538 4 8 411 7.4 8 109 446.50 552 124 2.2

Mar 2025 849 2 9 608 9.9 98 123 446.70 555 147 2.4

Apr 2025 1005 7 11 726 12.2 89 136 448.70 593 147 2.5

* Based on the Colorado River Basin Forecast Center's Most Probable Water Supply Forecast Model Run ID: 3224 Processed On: 5/9/2023 10:11:36AM 
Most Probable Inflow*

May 2023 24-Month Study

Hoover Dam - Lake Mead

OPERATION PLAN FOR COLORADO RIVER SYSTEM RESERVOIRS

Reservoir Elev

End of Month

(Ft)

Hoover

Gross Energy

MKWH

Hoover

Static Head

(Ft)

Power

Release

Date (1000 CFS)

Percent of 

Units

Available KWH/AF

Change In

Storage

(1000 Ac-Ft)

Power

Release

(1000 Ac-Ft)

EOM

Storage

(1000 Ac-Ft)

Hoover Gen

Capacity

MW

* May 2022 1083 17.6 1047.69 7517 -509 397.38 1082.0 391.7 80 361.7

H Jun 2022 889 14.9 1043.02 7187 -330 396.77 1076.9 315.1 81 354.6

I Jul 2022 822 13.4 1040.92 7041 -146 392.29 1236.6 287.9 94 350.1

S Aug 2022 573 9.3 1044.28 7275 234 399.70 1224.8 200.6 94 349.9

T Sep 2022 539 9.1 1045.03 7328 53 400.65 1157.3 188.5 88 349.7

WY 2022 8899 3240.9

O Oct 2022 418 6.8 1046.28 7417 88 402.36 924.5 145.8 70 348.8

R Nov 2022 713 12.0 1043.02 7187 -230 395.39 948.8 254.6 72 357.1

I Dec 2022 438 7.1 1044.82 7313 126 403.20 975.8 152.9 72 348.9

C Jan 2023 412 6.7 1046.97 7466 152 403.66 866.6 143.8 64 348.8

A Feb 2023 494 8.9 1047.02 7469 4 399.03 810.5 175.9 60 356.5

L Mar 2023 754 12.3 1046.03 7399 -70 397.62 863.6 270.4 65 358.8

* Apr 2023 831 14.0 1049.69 7661 262 402.80 839.3 300.5 65 361.7

May 2023 965 15.7 1052.77 7884 224 401.09 986.6 353.8 71 366.8

Jun 2023 866 14.5 1055.41 8079 194 403.19 1080.0 315.0 78 363.9

Jul 2023 818 13.3 1059.27 8367 289 405.40 1270.5 300.4 90 367.5

Aug 2023 762 12.4 1064.35 8757 389 409.46 1404.9 280.2 97 367.9

Sep 2023 688 11.6 1066.97 8960 204 413.62 1474.0 253.3 100 368.4

WY 2023 8157 2946.8

Oct 2023 459 7.5 1067.36 8991 30 421.33 924.9 173.3 63 377.6

Nov 2023 606 10.2 1066.22 8902 -89 423.25 924.9 232.1 63 382.8

Dec 2023 538 8.7 1067.32 8988 86 419.86 1101.0 198.9 75 370.0

Jan 2024 591 9.6 1069.38 9150 162 419.78 1027.0 221.9 69 375.6

Feb 2024 563 9.8 1070.76 9260 110 420.74 1027.0 212.2 69 377.2

Mar 2024 908 14.8 1068.70 9096 -163 418.68 1203.0 343.7 81 378.7

Apr 2024 1033 17.4 1063.64 8701 -395 412.80 1460.0 383.1 100 370.7

May 2024 1014 16.5 1058.23 8290 -412 407.64 1418.0 368.3 100 363.1

Jun 2024 898 15.1 1054.16 7986 -304 402.95 1390.0 324.1 100 361.0

Jul 2024 789 12.8 1052.85 7890 -96 400.61 1399.4 284.4 100 360.4

Aug 2024 751 12.2 1052.99 7900 10 400.36 1399.4 269.2 100 358.3

Sep 2024 673 11.3 1051.57 7797 -104 400.37 1399.4 239.2 100 355.3

WY 2024 8823 3250.3

Oct 2024 486 7.9 1053.69 7952 155 405.30 1098.4 177.3 78 364.7

Nov 2024 592 9.9 1054.45 8008 56 409.44 1028.8 217.2 74 367.2

Dec 2024 524 8.5 1057.25 8216 208 407.78 1219.3 187.1 86 357.2

Jan 2025 587 9.5 1061.09 8506 290 410.56 1008.5 215.3 70 367.0

Feb 2025 558 10.1 1064.02 8731 225 413.17 1023.2 207.5 70 371.7

Mar 2025 903 14.7 1063.45 8687 -44 412.19 1261.5 335.2 87 371.1

Apr 2025 1029 17.3 1059.68 8399 -288 409.62 1242.9 381.1 87 370.3

* Based on the Colorado River Basin Forecast Center's Most Probable Water Supply Forecast Model Run ID: 3224 Processed On: 5/9/2023 10:11:36AM 
Most Probable Inflow*

May 2023 24-Month Study

Davis Dam - Lake Mohave

OPERATION PLAN FOR COLORADO RIVER SYSTEM RESERVOIRS

Reservoir Elev

End of Month

(Ft)

Davis

Gross Energy

MKWH

Davis

Static Head

(Ft)

Power

Release

Date (1000 CFS)

Percent of 

Units

Available KWH/AF

Change In

Storage

(1000 Ac-Ft)

Power

Release

(1000 Ac-Ft)

EOM

Storage

(1000 Ac-Ft)

Davis Gen

Capacity

MW

* May 2022 1041 16.9 643.35 1708 7 140.42 241.8 132.1 95 126.9

H Jun 2022 842 14.1 643.47 1712 3 139.18 251.6 108.5 99 128.9

I Jul 2022 770 12.5 643.97 1725 14 144.37 255.0 99.3 100 129.1

S Aug 2022 575 9.3 642.87 1695 -30 141.93 253.3 74.7 99 129.9

T Sep 2022 617 10.4 639.17 1595 -100 137.50 248.2 78.5 97 127.3

WY 2022 8495 1074.5

O Oct 2022 540 8.8 633.78 1454 -141 134.35 185.9 66.9 73 123.8

R Nov 2022 516 8.7 640.22 1623 169 141.13 154.7 62.5 61 121.1

I Dec 2022 436 7.1 639.97 1617 -7 140.89 159.6 53.9 63 123.5

C Jan 2023 347 5.6 642.12 1675 58 143.26 157.9 44.3 62 127.7

A Feb 2023 429 8.0 643.00 1699 24 141.81 185.8 56.7 73 132.3

L Mar 2023 705 11.5 644.17 1731 32 141.44 215.5 93.4 85 132.4

* Apr 2023 844 14.2 642.84 1694 -36 138.90 255.0 108.3 100 128.3

May 2023 933 15.2 643.00 1699 4 139.11 255.0 116.9 100 125.3

Jun 2023 831 14.0 643.00 1699 0 139.61 255.0 104.5 100 125.8

Jul 2023 811 13.2 642.00 1671 -27 139.40 255.0 101.9 100 125.6

Aug 2023 730 11.9 642.00 1671 0 139.40 255.0 91.6 100 125.6

Sep 2023 719 12.1 640.01 1617 -54 138.32 255.0 89.6 100 124.6

WY 2023 7841 990.5

Oct 2023 617 10.0 633.00 1434 -183 134.64 227.0 74.8 89 121.3

Nov 2023 526 8.8 635.00 1486 51 132.63 159.8 62.9 63 119.5

Dec 2023 405 6.6 639.51 1604 118 136.90 154.7 49.9 61 123.3

Jan 2024 509 8.3 641.80 1666 62 139.53 156.3 64.0 61 125.7

Feb 2024 542 9.4 641.80 1666 0 140.19 160.0 68.5 63 126.3

Mar 2024 853 13.9 643.05 1700 34 139.08 194.1 106.9 76 125.3

Apr 2024 1009 17.0 643.00 1699 -2 138.62 249.9 126.0 98 124.9

May 2024 987 16.0 643.00 1699 0 138.89 255.0 123.5 100 125.1

Jun 2024 863 14.5 643.00 1699 0 139.43 255.0 108.4 100 125.6

Jul 2024 783 12.7 642.00 1671 -27 139.57 255.0 98.4 100 125.7

Aug 2024 719 11.7 642.00 1671 0 139.47 255.0 90.4 100 125.7

Sep 2024 705 11.8 640.01 1617 -54 138.42 255.0 87.9 100 124.7

WY 2024 8518 1061.6

Oct 2024 644 10.5 633.00 1434 -183 134.45 227.0 78.0 89 121.1

Nov 2024 512 8.6 635.00 1486 51 132.74 159.8 61.2 63 119.6

Dec 2024 391 6.4 639.51 1604 118 137.00 154.7 48.3 61 123.4

Jan 2025 505 8.2 641.80 1666 62 139.56 156.3 63.5 61 125.7

Feb 2025 538 9.7 641.80 1666 0 140.07 156.6 67.9 61 126.2

Mar 2025 849 13.8 643.05 1700 34 139.11 194.1 106.4 76 125.3

Apr 2025 1005 16.9 643.00 1699 -2 138.64 249.9 125.5 98 124.9

* Based on the Colorado River Basin Forecast Center's Most Probable Water Supply Forecast Model Run ID: 3224 Processed On: 5/9/2023 10:11:36AM 
Most Probable Inflow*

May 2023 24-Month Study

Parker Dam - Lake Havasu

OPERATION PLAN FOR COLORADO RIVER SYSTEM RESERVOIRS

Reservoir Elev

End of Month

(Ft)

Parker

Gross Energy

MKWH

Parker

Static Head

(Ft)

Power

Release

Date (1000 CFS)

Percent of 

Units

Available KWH/AF

Change In

Storage

(1000 Ac-Ft)

Power

Release

(1000 Ac-Ft)

EOM

Storage

(1000 Ac-Ft)

Parker Gen

Capacity

MW

* May 2022 741 12.0 448.68 593 30 84.09 120.0 51.5 100 69.5

H Jun 2022 679 11.4 448.30 586 -7 78.23 120.0 47.2 100 69.4

I Jul 2022 639 10.4 448.84 596 10 82.19 120.0 44.7 100 69.9

S Aug 2022 482 7.8 448.16 583 -13 83.58 120.0 33.4 100 69.3

T Sep 2022 458 7.7 447.96 579 -4 81.26 120.0 31.4 100 68.7

WY 2022 6231 431.0

O Oct 2022 393 6.4 447.14 564 -15 81.28 91.9 27.2 77 69.1

R Nov 2022 336 5.6 447.09 563 -1 82.54 82.0 22.8 68 68.0

I Dec 2022 277 4.5 447.06 562 0 82.38 60.0 18.5 50 66.8

C Jan 2023 261 4.2 447.14 564 2 81.41 72.6 17.3 60 66.4

A Feb 2023 357 6.7 447.47 570 6 81.43 94.3 25.4 79 71.2

L Mar 2023 553 9.0 448.31 586 16 81.24 120.0 38.6 100 69.8

* Apr 2023 669 11.2 447.68 574 -12 79.27 120.0 46.4 100 69.4

May 2023 680 11.1 448.00 580 6 78.30 116.1 47.4 97 69.8

Jun 2023 693 11.6 448.00 580 0 78.23 120.0 48.3 100 69.7

Jul 2023 708 11.5 448.00 580 0 78.28 120.0 49.1 100 69.4

Aug 2023 625 10.2 447.50 571 -9 78.56 120.0 43.4 100 69.4

Sep 2023 537 9.0 447.50 570 0 78.80 120.0 37.2 100 69.3

WY 2023 6088 421.8

Oct 2023 466 7.6 447.50 571 0 79.46 91.0 32.7 76 70.3

Nov 2023 365 6.1 447.50 570 0 80.16 92.0 25.1 77 68.7

Dec 2023 263 4.3 446.50 552 -19 80.65 112.3 16.7 94 63.7

Jan 2024 313 5.1 446.50 552 0 79.71 92.9 20.9 77 66.8

Feb 2024 411 7.1 446.50 552 0 78.66 96.2 28.4 80 69.1

Mar 2024 608 9.9 446.70 555 4 77.53 120.0 41.7 100 68.6

Apr 2024 727 12.2 448.70 593 38 77.71 120.0 50.5 100 69.5

May 2024 734 11.9 448.70 593 0 78.82 120.0 51.5 100 70.2

Jun 2024 714 12.0 448.70 593 0 78.79 120.0 50.1 100 70.2

Jul 2024 686 11.2 448.00 580 -13 78.77 120.0 47.9 100 69.8

Aug 2024 621 10.1 447.50 571 -10 78.59 120.0 43.1 100 69.4

Sep 2024 533 9.0 447.50 570 0 78.83 120.0 36.9 100 69.3

WY 2024 6439 445.6

Oct 2024 482 7.8 447.50 571 0 79.34 90.0 33.8 75 70.1

Nov 2024 375 6.3 447.50 570 0 80.08 92.0 25.7 77 68.6

Dec 2024 270 4.4 446.50 552 -19 80.59 114.2 17.2 95 63.6

Jan 2025 313 5.1 446.50 552 0 79.71 92.9 20.9 77 66.8

Feb 2025 411 7.4 446.50 552 0 78.54 95.4 28.4 79 69.0

Mar 2025 608 9.9 446.70 555 4 77.53 120.0 41.7 100 68.6

Apr 2025 726 12.2 448.70 593 38 77.71 120.0 50.5 100 69.5

* Based on the Colorado River Basin Forecast Center's Most Probable Water Supply Forecast Model Run ID: 3224 Processed On: 5/9/2023 10:11:36AM 
Most Probable Inflow*

May 2023 24-Month Study

Upper Basin Power

OPERATION PLAN FOR COLORADO RIVER SYSTEM RESERVOIRS

Fontenelle

Reservoir

1000 MWHR

Crystal

Reservoir

1000 MWHR

Glen

Canyon

Date 1000 MWHR

Flaming

Gorge

1000 MWHR

Blue 

Mesa

1000 MWHR

Morrow

Point

1000 MWHR 

* May 2022 214 52 20 31 18 3

H Jun 2022 222 41 18 25 16 6

I Jul 2022 251 29 23 29 17 7

S Aug 2022 265 39 23 31 18 6

T Sep 2022 201 42 14 27 13 5

Summer 2022 1332 222 108 160 92 28

O Oct 2022 175 42 0 21 10 2

R Nov 2022 181 38 0 6 2 1

I Dec 2022 199 40 1 6 2 4

C Jan 2023 182 41 4 5 2 4

A Feb 2023 172 37 5 6 0 1

L Mar 2023 173 23 4 6 0 3

Winter 2023 1083 220 15 49 16 15

* Apr 2023 291 17 5 9 3 4

May 2023 397 17 27 44 23 6

Jun 2023 418 53 25 37 22 7

Jul 2023 467 29 33 40 21 8

Aug 2023 474 32 33 40 20 7

Sep 2023 362 34 8 37 18 4

Summer 2023 2409 181 132 207 108 37

Oct 2023 191 20 21 25 9 4

Nov 2023 198 19 15 19 10 4

Dec 2023 237 30 28 34 17 5

Jan 2024 283 30 13 16 9 4

Feb 2024 249 28 12 15 8 4

Mar 2024 262 21 14 17 9 3

Winter 2024 1419 149 102 126 62 24

Apr 2024 233 20 14 21 12 2

May 2024 237 76 24 37 22 6

Jun 2024 256 21 41 53 22 7

Jul 2024 293 25 34 40 21 8

Aug 2024 312 35 35 41 21 7

Sep 2024 234 37 32 38 19 6

Summer 2024 1566 215 180 229 117 36

Oct 2024 263 26 26 32 10 4

Nov 2024 261 27 14 18 9 4

Dec 2024 289 42 19 24 12 4

Jan 2025 346 42 15 18 10 3

Feb 2025 300 38 13 17 9 3

Mar 2025 319 21 11 15 8 3

Winter 2025 1778 195 99 123 58 20

Apr 2025 283 20 12 19 11 2

* Based on the Colorado River Basin Forecast Center's Most Probable Water Supply Forecast Model Run ID: 3224 Processed On: 5/9/2023 10:11:36AM
Most Probable Inflow*

May 2023 24-Month Study

Flood Control Criteria - Beginning of Month Conditions

OPERATION PLAN FOR COLORADO RIVER SYSTEM RESERVOIRS

Navajo

Date KAF

Flaming

Gorge

KAF

Blue

Mesa

KAF

Lake

Powell

KAF

Upper Basin

Total

KAF

Lake

Mead

KAF

Total

KAF

Flaming

Gorge

KAF

Blue

Mesa

KAF

Navajo

KAF

Lake

Powell

KAF

Tot or Max

Allow

KAF

Lake

Mead

KAF

Total

KAF

BOM Space

Required

KAF

Mead 

Sched Rel

KAF

Mead 

FC Rel

KAF

Sys

Cont

MAF

* * * * P R E D I C T E D S P A C E * * * * * * * * E F F E C T I V E S P A C E * * * *

May 2023 1,295 466 524 17769 20055 19959 40014 819 466 261 1546 17769 19959 39275 1500 965 0 22.8

Jun 2023 949 325 361 15763 17398 19736 37134 455 309 61 825 15763 19736 36323 1500 866 0 25.8

Jul 2023 638 72 399 13468 14576 19541 34118 122 28 47 197 13468 19541 33206 1500 818 0 26.3

* * * * C R E D I T A B L E S P A C E * * * *

Aug 2023 534 43 408 13396 14381 19253 33633 534 43 408 985 13396 19253 33633 1500 762 0 26.0

Sep 2023 561 76 428 13972 15037 18863 33900 561 76 428 1065 13972 18863 33900 2270 688 0 25.6

Oct 2023 623 129 433 14353 15539 18660 34199 623 129 433 1186 14353 18660 34199 3040 459 0 25.4

Nov 2023 639 155 425 14403 15622 18629 34252 639 155 425 1219 14403 18629 34252 3810 606 0 25.3

Dec 2023 647 174 424 14422 15667 18718 34385 647 174 424 1245 14422 18718 34385 4580 538 0 25.2

Jan 2024 705 238 425 14552 15919 18632 34552 705 238 425 1367 14552 18632 34552 5350 591 0 25.1

* * * * E F F E C T I V E S P A C E * * * *

Jan 2024 705 238 425 14552 15919 18632 34552 412 208 147 767 14552 18632 33951 5350 591 0 25.1

Feb 2024 755 255 429 14841 16280 18470 34750 460 227 151 837 14841 18470 34149 1500 563 0 25.0

Mar 2024 798 271 425 15024 16518 18360 34879 502 244 146 891 15024 18360 34275 1500 908 0 24.8

Apr 2024 779 278 380 15154 16592 18524 35116 478 252 94 824 15154 18524 34502 1500 1033 0 24.7

May 2024 734 245 317 15030 16327 18919 35245 427 220 7 654 15030 18919 34603 1500 1014 0 25.6

Jun 2024 728 130 384 13772 15015 19330 34345 415 97 35 546 13772 19330 33649 1500 898 0 26.9

Jul 2024 423 26 435 12512 13396 19634 33030 89 -22 29 96 12512 19634 32242 1500 789 0 26.7

* * * * C R E D I T A B L E S P A C E * * * *

Aug 2024 353 38 465 12571 13426 19730 33156 353 38 465 855 12571 19730 33156 1500 751 0 26.3

Sep 2024 405 80 496 12837 13818 19720 33537 405 80 496 980 12837 19720 33537 2270 673 0 25.9

Oct 2024 484 138 501 12968 14091 19823 33915 484 138 501 1123 12968 19823 33915 3040 486 0 25.6

Nov 2024 516 188 496 13136 14336 19668 34004 516 188 496 1200 13136 19668 34004 3810 592 0 25.5

Dec 2024 549 205 496 13303 14552 19612 34164 549 205 496 1249 13303 19612 34164 4580 524 0 25.4

Jan 2025 638 241 500 13533 14912 19404 34317 638 241 500 1379 13533 19404 34317 5350 587 0 25.3

* * * * E F F E C T I V E S P A C E * * * *

Jan 2025 638 241 500 13533 14912 19404 34317 351 216 492 1059 13533 19404 33996 5350 587 0 25.3

Feb 2025 720 265 504 13911 15399 19114 34513 432 240 496 1168 13911 19114 34193 1500 558 0 25.2

Mar 2025 789 284 499 14176 15749 18889 34638 501 261 491 1253 14176 18889 34318 1500 903 0 25.0

Apr 2025 770 285 454 14431 15939 18933 34872 477 263 438 1178 14431 18933 34542 1500 1029 0 24.9

* Based on the Colorado River Basin Forecast Center's Most Probable Water Supply Forecast Model Run ID: 3224 Processed On: 5/9/2023 10:11:36AM