Southern California Water Dialogue May 25, 2016
Southern California Water Dialogue May 25, 2016
5,200 Square Miles
4 MAF Annual Demand
19 Million People
26 Member Agencies
Water Wholesaler
MWD Service Area
Imported Supplies
Local Supplies
Lake Mead
Upper Colorado
River Basin
Colorado River
• Annual aqueduct capacity: 1.25 MAF
• 242 miles of aqueduct
• 550 TAF basic apportionment
Lake Powell
Colorado River Aqueduct
Whitsett Intake
Range of Deliveries past 15 years:
0.44 – 1.25 MAF
San Luis Reservoir
Lake Oroville Sacramento River
• Total Contract Supplies: 4.2 MAF • 29 Contractors
• Metropolitan largest (1.9 MAF)
Feather River
Bay Delta San Joaquin
River
California Aqueduct
Banks Pumping Plant
Range of deliveries to MWD past 15 years:
0.6 – 1.8 MAF
0.51.01.52.02.53.03.54.0
Dec-11 Dec-12 Dec-13 Dec-14 Dec-15
Mill
ion
Acre
-Fee
t
Oroville Storage
910111213141516
Dec-11 Dec-12 Dec-13 Dec-14 Dec-15
Mill
ion
Acre
-Fee
t
Lake Mead Storage
Lowest since 1977
Lowest since 1937 Allen J. Schaben / Los Angeles Times
0369
121518
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
Runo
ff (M
AF)
05
101520253035
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
Runo
ff (M
AF)
18.26 MAF
Northern Sierra Actual Average
10.83 MAF
Below Average Runoff 8 out of last 10 years
Below Average Runoff 13 out of last 16 years
Lake Powell
Upper Colorado
Lake Oroville
Lake Shasta
April 1, 2015 Randall Benton / Sacramento Bee
Randall Benton / Sacramento Bee
? Cooler & Wetter
Wet
Dry
Warmer
Mild
Increased Hurricane
Activity
Decreased Hurricane
Activity
-1.0
-0.5
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun
Dep
artu
re fr
om N
orm
al ˚C
1997-1998
Very Strong El Niño
2015-2016
Southern California is much drier than average Northern California is wetter than average
Percent of Average Precipitation (%) 10/1/2015 – 5/22/2016
WATER YEAR
OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP
Initial allocation on December 1
Lake Oroville San Luis Reservoir
Projected Dry Hydrologic Conditions
+ +
Initial allocation on December 1
WATER YEAR
OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP
Mostly falls October through April
50 inches
average
56.5 inches Average
to date
WATER YEAR
OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP
Supported by Developing Hydrologic Conditions
10% initial
15% 30%
45% 60%
No further increases expected
WATER YEAR
Usually peaks in early April
29 inches
average 4/1
Apr. 1 avg
Last year
OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP
Maximum Capacity 3.5 MAF
WATER YEAR
OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP
Record Low Storage – Sep 1977
Last year
This year
Average Storage
Flood releases end of March 2016
Improved Starting
Conditions for 2017
WATER YEAR
Distributed throughout the year 31
inches average
23.6 inches
OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP
Average to date
WATER YEAR
Usually accumulates through March 16
inches average 4/1
Apr. 1 avg
OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP
WATER YEAR
USBR’s August forecast determines Mead and Powell operations for upcoming calendar year USBR’s April forecast can result in modified reservoir operations for current calendar year
OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP CALENDAR YEAR
End of Year Storage in Lake Mead
1,075’
USBR April Forecast of Lake Mead Elevation
2016 2017 1,050’
1,100’
1,125’
1,075’ Shortage Trigger
Actual
Most Probable
End of CY 2016 1,078.8 ft End of CY 2017
1,074.1 ft
10% Chance of Shortage in 2017
56% Chance of Shortage in 2018
Supplies Demands
Supplies Demands
250
350
450
550TAF DVL Storage
2014 2015 2016
Frank Bellino / Press Enterprise
Castaic Lake
50
150
250TAF
Castaic Lake Storage
2014 2015 2016
2.2 1.8 1.1 1.0
1.7 2.4 2.7 2.3
1.2
0
1
2
3
4
5
2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016
Mill
ion
Acre
-Fee
t
Emergency Storage Dry-Year Storage
End of Year Balances
0.9
1.1- 1.5-
Improved hydrologic conditions in northern CA SWP reservoirs filling and allocation increased 2017 starting conditions improved Metropolitan will add to storage in 2016
Regional call for conservation through drought ordinances and other measures One normal hydrologic year will not end drought
Drought severity has reduced Need for continued conservation practices