United States Department of the Interior
Fish and Wildlife Service
Buenos Aires, Leslie Canyon, & San Bernardino National Wildlife Refuges
P.O. Box 3509 7628 North Hwy. 191
Douglas, Arizona 85608
05 January 2020
Memorandum
To: Tasha Harden, Assistant Manager, San Bernardino National Wildlife Refuge
From: Cassondra Walker, Refuge Biologist, San Bernardino National Wildlife Refuge
Subject: Status Monitoring Wells and Ponds on San Bernardino NWR: Updated week of 30 Dec 19
San Bernardino has nine monitoring wells, three are fitted with transducers that monitor water temperature, depth to
water, and well pressure: Hay Hollow Ponds, Hay Hollow Upstream, and Hay Hollow Downstream. The remaining six
wells are monitored with a tape piezometer to determine depth to water: Frog, Cemetery North, Cemetery South, Black
Draw East, Black Draw North, and Black Draw South. A new well added to Slaughter Ranch will be monitored after well
is completed and fitted with monitoring equipment. Seven other wells located on refuge provide water to refuge ponds for
critical habitat for three species of endangered Rio Yaqui fishes. Additionally, 18 refuge ponds and 1 pond on Slaughter
Ranch are monitored. Below are relative locations for wells and ponds regularly monitored. With increased water usage
off refuge in association with border wall construction, the frequency of refuge water resources has increased.

 Refuge ponds showed variable levels, with some remaining constant across 2019, whereas others showed high changes in
response to several factors. Ponds that have shown little to moderate change are: North and South Minckley and Oasis.
Water to Mesquite pond was turned off on 21 October to control cattail and as Mesquite dried, slight bumps in Oasis and
the Minckleys were noticed. Solar power was turned off on 22 November 2019, many ponds with wells that have
associated solar panels showed immediate responses, specifically, the Phd ponds. The Hackberry ponds, Hay Hollow
ponds, and North ponds did show a slight response as well, but not as dramatic as the Phds. Hay Hollow ponds and North
ponds dropped further when water was turned off for well pressure monitoring. Water to these ponds was turned back on
as pond levels became alarmingly low. Water to Hay Hollow and North ponds continues to be turned on off to both
monitor well pressure and keep pond levels from dropping to far and endangering resident Rio Yaqui fishes. See the
following figures:

Hay Hollow Well Pond Levels
1.8
1.6
1.4
1.2

1Ja
1- n -1
M 8
1- ar-1
M 8
a
1- y-1
Ju 8
n
1- -18
Ju
1- l-1
Se 8
1- p-1
O 8
c
1- t-1
N 8
o
1- v-1
Ja 8
1- n -1
Fe 9
1- b-1
M 9
a
1- r-1
Ap 9
r
2 -1
12 -Ju 9
-A l-19
u
3- g-1
Se 9
18 p
-S -19
e
2- p-1
O 9
c
1- t-1
N 9
o
8- v-1
N 9
14 ov
-N -19
22 ov
-N -19
22 ov
-N -19
25 ov
-N -19
o
2- v-1
D
e 9
6- c-1
D
10 ec 9
-D -1
13 ec 9
-D -1
16 ec 9
-D -1
20 ec 9
-D -1
27 ec 9
-D -19
e
3- c-1
Ja 9
n20

1

S Hay Hollow

N Hay Hollow

Bath House Well Pond Levels
Solar on

2
1.75
1.5
1.25
1

1 9 19 r-19 r-19 l-1 9 -1 9 -19 -19 -19 -1 9 -1 9 -19 -19 -19 -19 -19 -19 -19 -19 -1 9 -1 9 -1 9 -20
n - eba Ap
ov
ov
ov
ov
ov
ov
ec
ec
ec
ec
ec
ec
ec
ep
a
Ju
ep
ep
an
ug
J
F
M
2- 2-A 3-S 8-S 0-S 1-N 8-N 4-N 1-N 5-N 9-N 1-D 2-D 6-D 1-D 3-D 0-D 7-D 3-J
11111
2
2
2
1
1
3
1
1
2
2

Bath House

Phd 1

Phd 2

 1Ja
n1- 19
Fe
b1- 19
M
ar
-1
9
1Ap
r-1
9
2Ju
12 l-1
9
-A
ug
-1
39
Se
p18
19
-S
ep
-1
30
9
-S
ep
-1
19
N
ov
-1
89
N
ov
-1
14
-N 9
ov
-1
21
-N 9
ov
-1
25
-N 9
ov
-1
29
-N 9
ov
-1
29
D
ec
-1
69
D
ec
-1
11
-D 9
ec
-1
13
-D 9
ec
-1
20
9
-D
ec
-1
27
9
-D
ec
-1
9
3Ja
n20

1Ja
n
1- -19
Fe
b
1- -19
M
ar
1- 19
Ap
r-1
9
2Ju
12 l-1
9
-A
ug
3- -19
Se
18 p-1
9
-S
e
30 p-1
9
-S
ep
1- -19
N
ov
8- -19
N
o
14 v-1
-N 9
o
21 v-1
-N 9
o
22 v-1
-N 9
o
25 v-1
-N 9
o
27 v-1
-N 9
o
29 v-1
-N 9
ov
2- -19
D
ec
6- -19
D
e
11 c-1
9
-D
e
13 c-1
-D 9
e
20 c-1
9
-D
e
27 c-1
-D 9
ec
3- 19
Ja
n20

2.25

Robertson Cienega

2

1.75

1.5

9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
0
9
19
-1
-1
-1
-1
-1
-1
-1
-1
-2
-1
-1
-1
-1
-1
-1
-1
-1
r-1 pr-1 ul-1
tv
v
v
v
v
v
c
c
c
c
c
c
p
n
n
b
g
a
c
o
o
o
o
o
o
e
e
e
e
e
e
J
e
u
Ja
Ja
A
Fe
M
O
N
N
N
N
N
N
2-S
-D
-D
-A
-D
-D
-D
-D
1131111841593
2
6
2
1
3
0
7
1
2
2
2
1
1
1
2
2

2

Hackberry Well Pond Levels

1.5

1

0.5

0

Ben New
Brasher
Cobble

Twin 2
Magoffin

Twin Well Pond Levels

Twin 1
Urquides

Water of
Water on Boards removed Twin 2

2

1.5

1

0.5

0

 Oasis Well Pond Levels
2.5
2
1.5
1
0.5
1Ja
n19
1Fe
b19
1M
ar
-1
9
1Ap
r-1
9
2Ju
12 l-19
-A
ug
-1
9
3Se
p19
18
-S
ep
-1
9
2O
ct
-1
9
1N
ov
-1
9
8N
ov
-1
14
9
-N
ov
-1
21
9
-N
ov
-1
25
9
-N
ov
-1
9
2D
ec
-1
9
6D
ec
-1
11
9
-D
ec
-1
13
9
-D
ec
-1
20
9
-D
ec
-1
27
9
-D
ec
-1
9
3Ja
n20

0

Oasis

Mesquite

N Minckley

S Minckley

Bunting Well Pond Level
2
1.6
1.2
0.8
0.4

1Ja
n19
1M
ar
-1
9
1Ap
r-1
9
2Ju
12 l-19
-A
ug
-1
9
3Se
p19
2O
ct
-1
9
1N
ov
-1
9
8N
ov
-1
14
9
-N
ov
-1
21
9
-N
ov
-1
25
9
-N
ov
-1
27
9
-N
ov
-1
9
3D
ec
-1
9
6D
ec
-1
10
9
-D
ec
-1
11
9
-D
ec
-1
13
9
-D
ec
-1
20
9
-D
ec
-1
27
9
-D
ec
-1
9
3Ja
n20

0

Water flow into the ponds was reduced when solar power was turned off the following wells (22 Nov 19): Bath House,
Hackberry, and North (Bunting). In order to test the pressure at several wells, water has been turned off and on to ponds,
specifically Hay Hollow, Bunting, and Twin. See figures below.

Hay Hollow Well
Pond Flows
Water on
Water of

8

Water of

Flow Rate (gal/min)

6
4
2
0

12

-N

9
-1
ov
1

9
-1
ov
N
3-

2

9
-1
ov
N
2-

9
-1
ov

-N
26
N Hay Hollow

9
-1
ec
D
6S Hay Hollow

1

9
-1
ec
D
9-

2

9
-1
ec
D
3-

3

9
-1
ec
D
0-

 Flow Rate (gal/min)

Bath
House Pond Flows
Solar of

140
120
100
80
60
40
20
0

Water on

9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
19
-1
-1
-1
-1
-1
-1
-1
-1
-1
-1
-1
-1
-1
-1
-1
-1
tt
t
t
t
v
v
v
v
v
v
v
c
c
c
c
p
c
c
c
c
c
o
o
o
o
o
o
o
e
e
e
e
O
N
Se
D
-O
-O
-O
-O
-N
-N
-N
-N
-N
-N
-D
-D
-D
25361
8
3
10
16
21
30
13
22
25
25
25
26
1
1
2

Bath House

Phd 1

Hack Berry Well Pond Flows

Flow Rate (gal/min)

18
16
14
12
10
8
6
4
2
0

3

9
-1
p
Se
0-

25

9
-1
t
c
-O

9
9
9
-1
-1
-1
c
c
c
e
e
e
-N
-N
-D
-D
-D
6
1
8
22 Ben New 26
Brasher
Cobble1
Magoffin
1
9
-1
v
o

9
-1
v
o

2

9
-1
c
e
D
3-

2

0
-2
n
-J a

Flow Rate (gal/min)

Oasis Well Pond Flows
35
30
25
20
15
10
5
0

9
9
9
9
9
9
19
19
19
19
19
19
19
19
-1
-1
-1
-1
-1
-1
tttvvvvvc
c
c
c
c
p
c
c
c
o
o
o
o
o
e
e
e
e
e
e
N
N
D
-O
-O
-O
-N
-N
-N
-S
-D
-D
-D
-D
56616
25
30
13
22
26
30
11
19
23
31

Mesquite

Oasis

S Minckley

N Minckley

 fow Rate (gal/min)

Bunting Well Pond Flow

Water of

60
50
40
30
20
10
0

9
9
9
9
9
19
19
19
19
19
19
19
19
19
19
-1
-1
-1
-1
-1
vvvvcccccpct
ct
ct
ct
ct
o
o
o
o
e
e
e
e
e
e
O
N
D
-O
-O
-O
-O
-N
-N
-N
-S
-D
-D
-D
-D
25610
16
21
30
13
22
26
30
11
18
23
31

North

All monitoring wells on San Bernardino are monitored with a tape piezometer, the depth to water is measured from the
top of the well casing. Monitoring frequencies in 2019 started as monthly, were increased to bimonthly, and is currently
conducted weekly. All monitoring wells show a decrease in depth to water with the exception of Hay Hollow
Downstream.

Depth to Water (ft)

Hay Hollow Monitoring Well
25
23
21
19
17
15
13
11
9
7
5

8
8
9
9
9
9
9
9
0
9
9
9
9
9
9
9
9
9
9
9
9
-1 n-1 b-1
-1
-1 g-1 p-1 p-1
-1
-1
-1
-1
-1 c -1
-1
-1
-1 n-2
-1
-1
-1
l
r
t
t
y
v
v
v
v
c
c
c
c
b
a
c
c
o
o
a
o
o
e
e
e
e
e
Ju
e
e
e
u
Ja
Fe
-Ju
-O 8-O
-F 8-M
-N 8-N 4-N 2-N
2- 2-A 3-S 8-S
-M
-D 6-D 3-D 0-D 7-D
37- 26
3
8
1
5
2
2
2
1
1
2
1
1
1
1
2
2

Hay Hollow Ponds

Hay Hollow Downstream

Hay Hollow Upstream

Frog Monitoring Well

Depth to Water (ft)

12
11.5
11
10.5
10

15

ct
-O

9
-1
N
1-

9
-1
v
o

N
8-

9
-1
v
o
14

9
-1
v
o
-N

21

9
-1
v
o
-N

29

9
-1
v
o
-N

2

9
-1
c
e
-D

6

9
-1
c
e
-D

13

9
-1
c
e
-D

20

9
-1
c
e
-D

27

9
-1
c
e
-D

3

0
-2
n
-J a

 Cemetery Monitoring Wells
Depth to Water (ft)

30
29
28
27
26
25
24
23
22

1

ct
O
5

9
-1
N
1-

9
-1
ov

N
8-

9
-1
ov
1

9
-1
ov
N
4-

2

9
-1
ov
N
1-

2

9
-1
ov
N
9-

2

Cemeterty North

9
-1
ec
-D

6

9
-1
ec
-D

13

9
-1
ec
-D

20

9
-1
ec
-D

27

9
-1
ec
-D

3

20
na
-J

3

0
-2
n
-J a

Cemetery South

Depth to Water (ft)

Black Draw Monitoring Wells
17
16.5
16
15.5
15
14.5
14
13.5
13

17

ct
-O

9
-1
N
1-

9
-1
v
o

N
8-

9
-1
v
o
14

9
-1
v
o
-N

21

Black Draw East

9
-1
v
o
-N

29

9
-1
v
o
-N

2

9
-1
c
e
-D

Black Draw North

6

9
-1
c
e
-D

13

9
-1
c
e
-D

20

9
-1
c
e
-D

27

9
-1
c
e
-D

Black Draw South

Three of the monitoring wells, Hay Hollow Ponds, Hay Hollow Upstream, Hay Hollow Downstream, contain transducers
that measure water temperature, water pressure, and depth to water. These measurements are taken every hour. Depth to
water and pressure were averaged monthly and weekly for the current year and three previous years (approximately one,
five, and ten). Bars indicating one standard deviation are included to show changes in variation measurements for each
temporal frequency (monthly or weekly). Hay Hollow downstream had a transducer change between 2017 and 2018, and
the pressure measurements appear to be abnormally low. One trend across all three wells, is the increase in variation of
both depth and pressure measurements. Across the three wells, increases in variation in hourly measurements are
apparent; the standard deviation bars are larger. This suggests that range or difference in monthly or weekly minimums
and maximums is getting larger. It is clear that larger ranges in measurements occur in 2019 when compared to
comparable time periods of previous years. While yearly patterns are evident, the difference in measurements can be seen
across years, and in some cases 2019 breaks past patterns. With off refuge water use impacts on SBNWR water resources
unknown, the large differences in measurement (i.e. larger bars on graphs) for the last part of 2019 is concerning. The
cause for larger swings in depth to water and water pressure, is unknown but began to occur as water was used off refuge
for border wall construction. Further attention and incorporation of hydrology models is likely needed to understand these
new patterns.

 Pressure (PSI)

Depth to Water (ft)

4.0

3.5

Hay Hollow Ponds Pressure

2.5- . pg

2.0

20-

19-

18'

17-

16'

 

 

 

J?n Feb Mar A'pr Mey J'ul A?g S'ep o'ct NIOV Dec
Month
Hay Hollow Ponds Depth

 

J?n Feb Mar A'pr Mey J0n J01 Abg s?p o'ct Nev Dec
Month

Year

-Q- 2009
.- 2014
-Q- 2017
.- 2019

Year

0- 2009
.- 2014
-Q- 2017
.- 2019

Depth to Water (ft)

Pressure (PSI)

Hay Hollow Ponds Depth

202.5 



Week

Hay Hollow Ponds Pressure

 

2.0

 

 




VVeek

Year

0- 2009
.mu
.mw
0mm

Year

.- 2009
0mm
Own
.mm

Hay Hollow Upstream

 

 

 

 

13J?n F?b M'ar Alpr M?y J01 Abg s?p o'ct NEW D?c
Month
Hay Hollow Upstream
8.0-
7.6.5-
J?n F?b Mar Apr May J01 Ahg s?p o'ct N0v D?c

Month

Year

.- 2008
.- 2015
.- 2018
.- 2019

Year

.- 2008
.- 2015
-Q- 2018
.- 2019

Pressure (PSI)

Hay Hollow Upstream

 

 

 

 



Year
aw
1 2008
2015
.9 .
5 I I 0- 2013
D.
:0 2019
10- 
t? I


9 
8.

VVeek
Hay Hollow Upstream
w-
m-
Year
. 2008
i? 2015
0mm
I 2019

m- 

at N.
Mp-w
u.
M-

 



Depth to Water (ft)

Pressure (PSI)

43
I

 

Hay Hollow Pressure

 

23-

21-

Jan Feb Mar Apr May J01
Month
Hay Hollow Depth



 

Ailg Sep O'ct Nev Dec

11

 

Jan Feb Mar Apr may J01


A09 Sep O'ct Nev Dec

Year

.- 2009
.- 2015
.- 2017
.- 2019

Year

.- 2009
.- 2015
-.- 2017
.- 2019

23-

Depth to Water (ft)

21-





Hay Hollow Depth

 



 



VVeek

Hay Hollow Pressure

Pressure (PSI)
43.

 

 


Week

Year

.- 2009
.- 2015
0- 2017
2019

Year

.- 2009
-Q- 2015
.- 2017
O- 2019

Week of 30 Dec 19:


30 Dec 19 – North pond water turned off – pressure monitoring new log



02 Jan 20 – GPM calculated for Hay Hollow North pond, North pond, and Yaqui pond



02 Jan 20 – Hay Hollow water on - pressure monitored



02 Jan 20 – Twin 2 boards removed



03 Jan 20 – 11 shiner salvaged from Magoffin pond