WSP11706

• File Number: 8271.300
• Description: Colorado River Basin Salinity Control Program - General Information and Publications-Reports
• Basin: Colorado Mainstem
• Water Division: 5
• Date: 6/1/1980
• Title: Development of Procedures to Evaluate Salinity Management Strategies in Irrigation Return Flows
• Water Supply Pro - Doc Type: Report/Study

the Palo Vatde Inigation Oistrlct (Figure
2.6), vary considerably from one another.
While the outfall drain showed little vari-
ation in concentration (measured in tons/
ac-ft) with time, the Anderson drain showed
large fluctuations. Two possible causes
exist, 1) Anderson drain could still be
leaching residual salts (in a pattern varying
with the rate of irrigation) or 2) the amount
of effluent groundwater mixing with the
drainage waters could be higher and diluting
the drainage water during the low flow
season.

however, to be site specific. As evidence,
concentrations in the La Mess drain in the
Massilla Valley, California, (Figure 2,5)
have a cyclic trend with an Ee lower during
the summer than in the winter months. A
possible explanation for this phenomena
would be that the drain could still be
leaching the residual salts and had not
reached steady state conditions.

w
w
t.I)
en

2. The drainage water salinity concen...
tration time patterns in three drains in

~ EC
Z 1. FEATHER RIVER WATER 0,10
0 2, GRAND RIVER WATER 0,94
i=
=> 3. MISSOURI RIVER WATER 0,91
..J 4. SALT RIVER WATER 1.56
0 5, COLORADO RIVER WATER 1. 27
lI)
lI) 6. SEVIER RIVER WATER 2.03
0 7. GILA RIVER WATER 3.14
~ 20 8, PECOS RIVER WATER 3.26

lI)
!:i
~<l
(/)lI)
~ 15 10
m~
<l
~~to
.1-:
(/)~
z;;:
0<3
_w
~ g: -10
U~
I.J..lI)
o!:i
<l
::!: lI) -20
::>LL
(/)0
lI)
lI)
o
..J
t;j -30
z

G)
@

~

~

@

-40
0.10

0.15 0.20 0,25
LEACHING FRACTION, LF

0.30

Figure 2,3,

Net contribution of mineral weathering and salt precipitation expressed as per-
cent of salts applied in irrigation waters in calcarious 60i1s. (After Rhoades
et a1. 1974,)

8