Stream Temperature Variability as an Indicator of Groundwater-Surface Water Interactions in Two Groundwater-Fed Streams
(1)
(1)
M.A. Middleton (maberg@sfu.ca) and D. M. Allen (dallen@sfu.ca)
1) Department of Earth Sciences, Simon Fraser University, British Columbia, Canada
20
20
15
10
5
17
15
15
14
10
18
13
1
Jan-2009
May-2009
Aug-2009
Nov-2009
t
Bertrand Creek site is located along the Canada-US
Gravel
Bar
15
14
t
Water temperatures varied spatially and temporally in both
streams, however, the patterns differed between the streams.
t
Fishtrap Creek water temperatures were more stable and
maintained values near groundwater temperature despite
having less riparian cover, suggesting surficial geology exerts
greater influence on groundwater-surface water interactions and
resulting water temperature patterns.
border (Fig. 1).
t
Flows through Ft. Langley Formation (fine grained
glaciomarine deposit).
t
Through the study reach, there are abundant trees and
shrubs providing riparian cover and shade to the stream
(Fig. 2 Photo).
t
Stream flows through rural residential area.
Jul-2008
Figure 4: Mean annual precipitation, stream
discharge, and groundwater levels for the study
area. See site map below for locations..
t
Table 2 shows that groundwater temperature
maintains stable values annually.
t
Fishtrap Creek has less severe temperature
ranges, and an overall lower mean temperature
than Bertrand Creek.
13
t
Temperature dataloggers were installed at 19 locations
(Fig. 2) at the sediment-watero interface.
t
Local scale variability in owater temperature was
observed between the dataloggers (Fig. 3), with mean
variability of 1.19° C and a maximum variability of 5.82°
12
11
10
8
0
Oct-2008
5m
Datalogger Location ID
0
16
0
5
Datalogger Location ID
Jul-2008
In-stream
Vegetation
No Cover
1 - Datalogger
Location ID
t
The streams have precipitation dominated flow
regimes, with annual precipitation of 1500mm,
with 70% falling between October and May, and
less than 100mm as snow.
Oct-2008
Jan-2009
May-2009
Aug-2009
1
N
Flow
8
British
Columbia
Vancouver
Island
0
U.S.A.
t
Fishtrap Creek site is located along the Canada-US border (Fig. 1).
t
Flows through primarily Sumas Drift, which is a coarse-grained outwash
deposit that hosts the Abbotsford-Sumas aquifer (Fig. 1).
t
Through the study reach, there is limited riparian cover shading the
stream (Fig. 6 Photo).
t
In study area, there is abundant in-stream vegetation from reed grass.
t
Stream flows through agricultural zone, dominated by blueberry and
raspberry production.
11
t
Temperature dataloggers were installed at 15 locations (Fig. 6) at the
sediment-water interface.
t
Local scale variability in water temperature was observed between the
dataloggers (Fig. 5), with mean variability of 1.18° C and a maximum
variability of 6.35° C (Table 1).
2
20
40
10
30
0
20
-10
10
-20
0
Air Temp
Stream Temp
pattern as a result of having the same precipitation driven flow regime.
Within the seasonal trends, there are differences in the stream
t
temperature patterns between the streams.
10
Bertrand Creek temperatures show stronger influence from air
t
9
temperature, both daily and seasonally.
Stream temperatures reach greater seasonal extremes, and the mean
t
annual temperature during the study period is higher than in Fishtrap
Creek.
Bertrand Creek has lower discharge overall, but has larger storm flow
t
events during the winter.
8
occurs in late summer, approximately one month
after the minimum precipitation.
7
t
Groundwater levels lag minimum stream
6
with less daily and seasonal temperature fluctuations.
The stream temperatures remains closer to groundwater temperatures,
t
especially during the low flow period.
Fishtrap Creek temperatures are not as strongly influenced by storm
t
flow events observed in the stream hydrograph.
Figure 8
assumed to be sustained by baseflow as there are
no other significant inputs to the system.
4
1
Fishtrap Creek
12
50
40
Abbotsford-Sumas
Aquifer
4
10
30
8
20
6
10
4
1
Bridge
0
2
-10
-20
Nooksak R.
Salish sediments (fluvial, lacustrine)
Sumas Drift (till, sandy till)
Sumas Drift (sand, gravel, till lenses)
Fort Langley Formation (stony clays)
Study Sites (B=Bertrand, F=Fishtrap)
Figure 1: Location of study sites on Bertrand and Fishtrap Creeks in
southwest British Columbia. The surficial geology of the area comprises
Quaternary aged sediments.
Figure 2: Distribution of dataloggers over a short reach of Bertrand Creek. Photo
shows representative riparian cover and bed material.
Creek
Bertrand
Fishtrap
Number of
Data Loggers
19
15
Temperature Difference
(oC)
Mean Maximum Minimum
5.82
0.34
1.19
6.35
0.12
1.18
Table 1: Stream temperature variability (July 2008-October 2009)
B
F
BC
WA
Figure 6: Distribution of dataloggers over a short reach of Fishtrap Creek. Photo
shows lack of riparian shade, but abundant in-stream vegetation.
Abbotsford Int’l Airport
Climate Station
Environment Canada
Monitoring Well ABB01
BC Ministry of Environment
Observation Wells
Environment Canada and
USGS Hydrograph Station
Discharge
Fishtrap Creek temperatures exhibit buffering from air temperatures,
t
r.
Fish
trap
C
3
50
Both Bertrand (Fig. 7) and Fishtrap (Fig. 8) follow a similar seasonal
t
2 5 3
5
30
12
6
F
Pepin Br.
WA
Bertrand Cr.
BC
B
60
Groundwater Temp
t
During the low flow period, stream flow is
7
40
Flow
discharge by approximately two months.
Vancouver
500 km
70
Nov-2009
t
Figure 4 shows that minimum stream discharge
9
50
Temperature (°C)
18
Figure 5
Bertrand Creek
Mean Min. Max.
Parameter
Daily Air Temperature (oC) (Abbotsford
International Airport)
11.3
-11.9 37.6
B1 Stream Temperature (oC)
11.17
0.04
22.91
F1 Stream Temperature (oC)
10.96 0.76
19.38
B1 Discharge (m 3/s)
0.72
0.01
60.31
F1 Discharge (m3/s)
0.60
0.00
9.98
10.1
12.9
ABB01 Groundwater Temperature (oC) 11.6
Table 2: Summary of climate and stream data (2008-2009)
Discharge (m³/s)
water temperature, discharge, air temperature, and
groundwater temperature data were collected.
t
Two networks of temperature (Tidbit) loggers installed in
groundwater-fed streams (Fishtrap and Bertrand Creeks) in the
Lower Fraser Valley, British Columbia (Fig. 1).
t
The streams are both precipitation driven, but differ in their
surficial geology, land use, and riparian cover.
t
Temperature loggers were installed over short sections of
stream, in a variety of settings, with different amounts of
riparian cover, channel morphology, and bed material.
5m
0
Figure 3
Temperature (°C)
t
Over two low flow periods (July 2008 - October, 2009),
19
Figure 7
25
Temperature ( oC)
groundwater-surface water interactions.
t
Stability of groundwater temperature relative to stream
temperature is a feature that can help identify relative
groundwater inputs, and the processes influencing water
temperature.
Full Cover
Partial Cover
No Cover
1 - Datalogger
Location ID
25
Temperature ( oC)
Water temperature can be a useful tool for assessing
t
Stream Temperature and Discharge
Fishtrap Creek
Discharge (m³/s)
Climate and Hydrology
Bertrand Creek
Introduction
0
Groundwater Temp
Air Temp
Stream Temp
Discharge
Conclusions:
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Fishtrap Creek has less protection from riparian cover, which would be expected to
buffer daily and seasonal fluctuations in water temperatures, however, this creek has a
more stable water temperature regime relative to Bertrand Creek.
t
Fishtrap Creek temperatures follow the pattern of groundwater temperatures more
closely, suggesting a pattern of a gaining stream.
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The results suggest that surficial geology of each stream exerts a greater influence on
the groundwater-surface water interactions, and subsequently influence temperature.
t
Riparian cover does not appear to be the factor influencing overall water temperature
patterns, however it may increase temperature variability at the local scale.
t
Multiple measurements or dataloggers should be used to capture variability in water
temperatures