Post on 27-Jul-2020
Conservation and Local Resources Committee Item #4b January 9, 2018
Evapotranspiration Groundwater Recharge
Runoff to Ocean
Active
Passive 95% used
15.2 inches 8.7 MAF
745 TAF
325 TAF
7.2 MAF
Ventura
Los Angeles
Orange
San Diego
Santa Clara River Station 1111400
Santa Clara River Station 723
Tributary Area: 1,634 mi2
15.6 in
Active Recharge 48 TAF 95%
used
0
100,000
200,000
300,000
400,000
500,000
600,000
700,000
1997 1999 2001 2003 2005 2007 2009 2011 2013 2015
An
nu
al F
low
to
th
e O
cean
(A
FY) Median flow = 36,000 AFY
USGS Station offline due to bridge construction
C&LR Committee Item 4b Slide 7 01/09/2018
% of the time 0
20,000
40,000
60,000
80,000
100,000
120,000
Flo
w t
o O
cean
(A
F/d
ay)
64% 0 AF
20% 17 AF
10% 168 AF
5% 618 AF
1% 114,000 AF
64% 20% 10% 5%
1% (about 4 days)
Ballona Creek Station F38C-R
Malibu Creek Station F130-R
Topanga Creek Station F54C-R
Tributary Areas: Santa Monica Bay: 385 mi2 Los Angeles River: 834 mi2 San Gabriel River: 689 mi2
SG River Station F42B-R
Coyote Creek Station F354-R
LA River Station F319-R
15.7 in Active Recharge 196 TAF
88% used
0
500,000
1,000,000
1,500,000
2,000,000
19
97
19
99
20
01
20
03
20
05
20
07
20
09
20
11
20
13
20
15
Flo
w t
o t
he
Oce
an (
AFY
)
Median Flows = 362 TAFY
C&LR Committee Item 4b Slide 10 01/09/2018
Santa Monica Bay 16%
Los Angeles River 53%
San Gabriel River 31%
C&LR Committee Item 4b Slide 11 01/09/2018
0
20,000
40,000
60,000
80,000
100,000
120,000
140,000
Flo
w t
o O
cean
(A
F/d
ay)
% of the time
64% 700 AF
20% 866 AF
10% 1,196 AF
5% 2,858 AF
1% 129,000 AF
64% 20% 10% 5%
1% (about 4 days)
C&LR Committee Item 4b Slide 12 01/09/2018 s
Tributary Areas: Santa Ana : 2,650 mi2
Santa Ana River Below Chapman
Santiago Creek
Active Recharge 185 TAF
12.6 in
98% used
0
100,000
200,000
300,000
400,000
500,000
600,000
19
97
19
99
20
01
20
03
20
05
20
07
20
09
20
11
20
13
20
15
An
nu
al F
low
s to
th
e O
cean
(A
F)
Median Flows = 26,500 AFY
C&LR Committee Item 4b Slide 14 01/09/2018
% of the time 0
5,000
10,000
15,000
20,000
25,000
30,000
Flo
w t
o O
cean
(A
F/d
ay)
64% 0 AF
20% 1 AF
10% 89 AF
5% 600 AF
1% 25,000 AF
64% 20% 10% 5%
1% (about 4 days)
C&LR Committee Item 4b Slide 15 01/09/2018 s
San Luis Rey River
Las Flores Creek
San Mateo Creek
San Juan Creek & Arroyo Trabuco
Cristianitos
Santa Margarita River
San Diego River
Active Recharge 8 TAF
10.4 in
98% used
0
100,000
200,000
300,000
400,000
500,000
600,000
700,000
19
97
19
99
20
01
20
03
20
05
20
07
20
09
20
11
20
13
20
15
Flo
w t
o t
he
Oce
an (
AFY
)
Median Flows = 49,000 AFY
C&LR Committee Item 4b Slide 17 01/09/2018
San Juan Creek
Watershed 34%
San Margarita River
Watershed 28%
San Luis Rey Watershed
19%
San Diego River
Watershed 19%
C&LR Committee Item 4b Slide 18 01/09/2018
% of the time 0
10,000
20,000
30,000
40,000
50,000
60,000
70,000
80,000
90,000
100,000
Flo
w t
o O
cean
(A
F/d
ay)
64% 70 AF
20% 181 AF
10% 459 AF
5% 927 AF
1% 90,000 AF
64% 20% 10% 5%
1% (about 4 days)
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
19
97
19
99
20
01
20
03
20
05
20
07
20
09
20
11
20
13
20
15
Flo
w t
o t
he
oce
an in
th
e M
WD
se
rvic
e a
rea
(MA
FY)
Median Flows = 457 TAFY
C&LR Committee Item 4b Slide 20 01/09/2018
% of the time 0
50,000
100,000
150,000
200,000
250,000
Flo
w t
o O
cean
(A
F/d
ay)
64% 800 AF
20% 1,135 AF
10% 2,233 AF
5% 5,856 AF
1% 239,000 AF
64% 20% 10% 5%
1% (about 4 days)
C&LR Committee Item 4b Slide 21 01/09/2018
Evapotranspiration
Groundwater Recharge
Runoff to Ocean
Active
Passive 95% used
15.2 inches 8.7 MAF
745 TAF
325 TAF 7.2 MAF
457 TAF
C&LR Committee Item 4b Slide 22 01/09/2018
Highly variable stormwater capture Most of the flow comes in a few days per year
Costs/Funding of stormwater projects SCWC Stormwater Task Force Report in April
Basin Management Review basin management practices regarding stormwater
Evaluate how stormwater is accounted for in safe yield calculations
C&LR Committee Item 4b Slide 24 01/09/2018
Data period
Water year 1997-2016
Daily streamflow data
USGS stream gauge data
County of Los Angeles Department of Public Works annual hydrology reports
Groundwater recharge data
Basin manager/watermaster reports
County of Los Angeles Department of Public Works annual hydrology report