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Garey A. Fox, Ph.D., P.E., Derek M. Heeren, Michael A. Kizer, Ph.D.Oklahoma State University
Evaluation of Alluvial Well Depletion Analytical Solutions from a Stream-Aquifer
Analysis Test
OKLAHOMA STATE UNIVERSITYBiosystems and Agricultural Engineering
Funding for this work provided by a FY 2010 Oklahoma Water Resources Research Institute (OWRRI) through the USGS 104(b) Program.
• Streams and Alluvial Aquifers– Hydraulically Connected/Single Resource– Alluvial Well Depletion– Protection of base flow currently not addressed in
water law systems of many states (OK)
Introduction
OKLAHOMA STATE UNIVERSITYBiosystems and Agricultural Engineering Department
Stream Depletion by Ground Water PumpingStream Depletion by Ground Water Pumping
Source: Winter et al., 1998, USGS Circular 1139
OKLAHOMA STATE UNIVERSITYBiosystems and Agricultural Engineering Department
Stream Depletion by Ground Water PumpingStream Depletion by Ground Water Pumping
Introduction• Rapid development of analytical solutions for
alluvial well depletion…• Suggested as alternative means of deriving
streambed conductivity, Ksb
Objectives
OKLAHOMA STATE UNIVERSITYBiosystems and Agricultural Engineering Department
Stream Depletion by Ground Water PumpingStream Depletion by Ground Water Pumping
• Evaluation of analytical solutions using field data from multiple geologic conditions is needed– Assessment of applicability and predictive capability
• Stream-Aquifer Analysis Test:– Pumping well adjacent to a
stream/river – North Canadian River in Oklahoma
– Drawdown response measured in multiple observation wells
– Stream depletion estimated not measured
Field Site
OKLAHOMA STATE UNIVERSITYBiosystems and Agricultural Engineering Department
Stream Depletion by Ground Water PumpingStream Depletion by Ground Water Pumping
• North Canadian River: – Sand bed, partially
penetrating stream – Connects Canton Lake in
the north and Lake Overholser in the south
• North of El Reno, OK in Canadian County
Field Site
OKLAHOMA STATE UNIVERSITYBiosystems and Agricultural Engineering Department
Stream Depletion by Ground Water PumpingStream Depletion by Ground Water Pumping
Site Characteristics
OKLAHOMA STATE UNIVERSITYBiosystems and Agricultural Engineering Department
Stream Depletion by Ground Water PumpingStream Depletion by Ground Water Pumping
• Surface geology is Quaternary alluvial sands and gravels (aeolian and fluvial in origin)
• Characterized as 15-20 m in thickness with widths of 1.6 km from the river
• Drillers’ logs report mostly fine sand with interdispersed clay
• Previous aquifer tests by Ryder (1996):• Specific yield = 0.29• Hydraulic Conductivity = 48 m/d
Streambed Sediment Sampling
OKLAHOMA STATE UNIVERSITYBiosystems and Agricultural Engineering Department
Stream Depletion by Ground Water PumpingStream Depletion by Ground Water Pumping
• Five streambed sediment samples…• Thalweg and near-bank sand bars• Sieve analysis for grain-size distribution
Particle Size (mm)
0.010.11
Per
cent
Fin
er (
%)
0
20
40
60
80
100
Sieve Analysis of Five Sediment SamplesBest Fit Trendline
d10 = 0.19 mm
d30 = 0.28 mm
d50 = 0.37 mm
d60 = 0.41 mm
d90 = 0.65 mm
Ksb = 30 m/d
(Alyamani and Sen, 1993)
Streambed Conductivity, Ksb
OKLAHOMA STATE UNIVERSITYBiosystems and Agricultural Engineering Department
Stream Depletion by Ground Water PumpingStream Depletion by Ground Water Pumping
• Falling-head permeameter tests:
Time (s)
0 50 100 150 200 250 300
He
ad
Dis
pla
cem
en
t a
bo
ve I
niti
al
Wa
ter
Le
vel (
m)
0.00
0.05
0.10
0.15
0.20
MeasuredPredicted (Darcy Equation)
tH
H
tt
dK sb
0
0
ln
Streambed Conductance, OKLAHOMA STATE UNIVERSITYBiosystems and Agricultural Engineering Department
Stream Depletion by Ground Water PumpingStream Depletion by Ground Water Pumping
• Streambed Conductivity, Ksb:• Average = 16.5 m/d• Standard Dev. = 3.1 m/d
• Width of River, W = 20-25 m
• Streambed Thickness, M = minimal restriction
dmOM
WK sb 1000
NCR - Falling-Head Permeameter
Sa
tura
ted
Hyd
rau
lic C
on
du
ctiv
ity,
Ksb
(m
/d)
0
5
10
15
20
25
Installation of Well Field
OKLAHOMA STATE UNIVERSITYBiosystems and Agricultural Engineering Department
Stream Depletion by Ground Water PumpingStream Depletion by Ground Water Pumping
• Observation wells installed using GeoProbe– Installed to 8 m depth with 5 m
of screened section at base
• Drawdown and temperature measured every 5 minutes using water level loggers (HoboWare)– Installed logger in river to
monitor stream stage and temperature
Long-Term Monitoring
OKLAHOMA STATE UNIVERSITYBiosystems and Agricultural Engineering Department
Stream Depletion by Ground Water PumpingStream Depletion by Ground Water Pumping
Date
10/3/09 10/7/09 10/11/09 10/15/09 10/19/09 10/23/09
Ele
vati
on
(m
)
102
103
104
105
106
107
Stream
F
G
H
Stream/Aquifer Analysis Test
OKLAHOMA STATE UNIVERSITYBiosystems and Agricultural Engineering Department
Stream Depletion by Ground Water PumpingStream Depletion by Ground Water Pumping
• Attempted to use several analytical solutions…– Hunt (1999) solution solved in Maple:
– Hunt (2003) solution for semiconfined aquifers
Tt
SL
ST
terfc
T
L
ST
t
Tt
SLerfc
Q
Qs4424
exp4
2222
0
22
1
22
1 /4
)/2(
/4
)(
4),,(
dSTt
yTxLEe
STt
yxLE
T
Qtyxsw
Stream/Aquifer Analysis Test
OKLAHOMA STATE UNIVERSITYBiosystems and Agricultural Engineering Department
Stream Depletion by Ground Water PumpingStream Depletion by Ground Water Pumping
Date
10/3/09 10/7/09 10/11/09 10/15/09 10/19/09 10/23/09
Ele
vati
on
(m
)
102
103
104
105
106
107
Stream
F
G
H
Stream-Aquifer Analysis Test
OKLAHOMA STATE UNIVERSITYBiosystems and Agricultural Engineering Department
Stream Depletion by Ground Water PumpingStream Depletion by Ground Water Pumping
(a) Observation Well F
Time, t (min)
10 100 1000 10000
Dra
wd
ow
n, s
w (
m)
0.0
0.2
0.4
0.6
0.8
1.0
ObservedTheis (1941) and Hunt (1999) SolutionsTheis (1935) Solution - No Stream
T = 860 m2/dSy = 0.28
> 600 m/d
Delayed-Yield Effects
Well Identification (Figure 1)
SSE n STDD Xa NOF
F 0.09 891 0.01 0.73 0.01 G 0.07 891 0.01 0.35 0.02 H 0.07 891 0.01 0.34 0.02
Stream-Aquifer Analysis Test
OKLAHOMA STATE UNIVERSITYBiosystems and Agricultural Engineering Department
Stream Depletion by Ground Water PumpingStream Depletion by Ground Water Pumping
Well Identification (Figure 1)
SSE n STDD Xa NOF
F 0.09 891 0.01 0.73 0.01 G 0.07 891 0.01 0.35 0.02 H 0.07 891 0.01 0.34 0.02
(c) Observation Well H
Time, t (min)
10 100 1000 10000
Dra
wd
ow
n, s
w (
m)
0.0
0.1
0.2
0.3
0.4
0.5
ObservedTheis (1941) and Hunt (1999) Solutions
T = 950 m2/dSy = 0.28
> 1500 m/d
Delayed-Yield Effects
Stream-Aquifer Analysis Test
OKLAHOMA STATE UNIVERSITYBiosystems and Agricultural Engineering Department
Stream Depletion by Ground Water PumpingStream Depletion by Ground Water Pumping
Time, t (min)
100 1000 10000
Str
eam
Dep
leti
on
, Q
s/Q
(%
)
0.0
0.2
0.4
0.6
0.8
1.0
Tt
SLerfc
Q
Qs4
2
Tt
SL
ST
terfc
T
L
ST
t
Tt
SLerfc
Q
Qs4424
exp4
2222
Conclusions
OKLAHOMA STATE UNIVERSITYBiosystems and Agricultural Engineering Department
Stream Depletion by Ground Water PumpingStream Depletion by Ground Water Pumping
• Stream-aquifer analysis test able to derive reach-scale conductance
• North Canadian River - fully penetrating stream with little to no hydraulic resistance– Estimated stream depletion of 60 to 70% of Q
after only 5 days of pumping• Advantages of earlier solutions:
– Considerably simplifies the mathematical complexity
– Reduced the number of parameters to parameterize the stream-aquifer interaction
Questions?
E-mail: [email protected]
Research Website: http://biosystems.okstate.edu/Home/gareyf
OKLAHOMA STATE UNIVERSITYBiosystems and Agricultural Engineering Department
Stream Depletion by Ground Water PumpingStream Depletion by Ground Water Pumping
Stream-Aquifer Analysis Test
OKLAHOMA STATE UNIVERSITYBiosystems and Agricultural Engineering Department
Stream Depletion by Ground Water PumpingStream Depletion by Ground Water Pumping
Well Identification (Figure 1)
SSE n STDD Xa NOF
F 0.09 891 0.01 0.73 0.01 G 0.07 891 0.01 0.35 0.02 H 0.07 891 0.01 0.34 0.02
(b) Observation Well G
Time, t (min)
10 100 1000 10000
Dra
wd
ow
n, s
w (
m)
0.0
0.1
0.2
0.3
0.4
0.5
ObservedTheis (1941) and Hunt (1999) Solutions
T = 790 m2/dSy = 0.19
> 1500 m/d
Delayed-Yield Effects