2. Overview of Water Year 2010
October 1, 2009 –September 30, 2010
El Niño conditions brought above average precipitation
and snowpack to the State Water Project
Final SWP Allocation at 50%
Dry conditions continued on the Colorado River Basin
Local supply conditions improved compared to WY
2009 with average to above average rainfall
2
3. Summary of Hydrologic Conditions
% of Average
Hydrologic Indicator
WY 2009 WY 2010
Statewide Precipitation 82 109
Statewide Reservoir
79 105
Storage (as of Sep. 30 )
th
Northern Sierra Snowpack
93 143
Maximum Accumulation
Sacramento River
70 86
Unimpaired Runoff
3
4. Combined Reservoir Storage
in Oroville and San Luis
6.0 Capacity San Luis Oroville
4.0
0.79 MAF 0.79 MAF 2.55 MAF
2.0 78% average
0.42 MAF
1.76 MAF
54% average 1.76 MAF
1.34 MAF
0.0
September 30, 2009 September 30, 2010
4
5. Ongoing Dry Conditions on the Colorado
River Basin in Water Year 2010
• Unregulated inflow to Lake Powell - 70% of normal
• Lake Mead at lowest level on Oct. 17, 2010 since filled
Storage Percent Capacity Storage in MAF*
Lake Powell 63 15.3
Lake Mead 39 10.2
Total System Contents 56 33.3
*As of September 20, 2010
• According to USBR, under certain hydrologic conditions
shortages could be experienced in 2012 Lake Mead
• Arizona and Nevada experience shortages first
5
6. Local Weather Conditions
Precipitation ranged from average to above average
in San Diego County
Summer temperatures in southern California were
below normal from the coast to the mountains
Coolest summer in San Diego since 1933
11th coolest summer on record
6
7. Total Local Reservoir Storage
Acre-feet
350,000
300,000
289 TAF
250,000
200,000
150,000
Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep
Average (2001-2010) WY 2009 WY 2010
7
8.
9. Local Weather Conditions
October precipitation was above average and
temperatures below average
Precipitation in San Diego
July 1- October 26 October 1 – 26
Station
Actual Normal Actual Normal
Lindbergh Field 2.08 0.66 2.03 0.33
Ramona Airport 3.35 2.28 3.14 1.60
9
10. Water Year 2011 Weather
3-Month Precipitation Outlook
La Nina conditions November 2010 – January 2011
are present and
expected last through
winter 2011
Often features above
average precipitation
in Pacific Northwest
and below average in
Southwest
A= Above Average
Source: National Weather Service Climate B= Below Average
Prediction Center October 21, 2010 EC= Equal Chance
10