Tamarack Project Background Information

• Description: Background on Tamarack Project inclduing notes, scopes of work, maps, meeting agendas and attendance records, and others.
• State: CO
• Basin: South Platte
• Water Division: 1
• Author: Various
• Title: Background on Tamarack Project related
• Water Supply Pro - Doc Type: Project Overview

Table 3 - Measured drawdown response in observation wells A15ES and B2ES,
located between the pumping well and slough channel.
Observation Well A15ES
Observation Well B2ES
Elapsed Time
Drawdown
Elapsed Time
Drawdown
(min)
(m)
(min)
(m)
0.00
0.000
0.00
0.000
11.38
0.049
12.87
0.034
13.30
0.052
14.00
0.034
18.57
0.058
19.67
0.040
39.70
0.079
40.58
0.052
48.58
0.085
49.35
0.055
62.85
0.088
63.72
0.061
83.30
0.101
84.05
0.070
114.72
0.119
113.67
0.076
144.78
0.128
143.27
0.085
191.97
0.143
191.18
0.098
347.18
0.192
349.50
0.131
599.42
0.262
600.50
0.177
1090.70
0.375
1091.72
0.247
1249.78
0.378
1250.62
0.262
1274.50
0.393
1275.90
0.268
1356.87
0.399
1357.53
0.277
1456.90
0.405
1456.32
0.287
Since observation wells A15ES and B2ES are located between the slough and
pumping well, these drawdown measurements will be used with an analytical solution to
estimate the sloughbed hydraulic conductivity. Note that finite stream width becomes
critical in influencing the interaction between the slough channel and the alluvial aquifer
since the distance between the slough and pumping well, L, is 94 m, resulting in an L/W
ratio of less than 15. It was shown by Fox et al. (2001) that finite stream width could be
ignored only if L/W is greater than 25. The distance between the South Platte River and
the slough channel is 380 m. -Therefore, the finite width of the slough channel presents a
significant impact on the slough/aquifer interaction. As such, the analytical solutions of
Hunt (1999) and the proposed analytical model, STRMAQ (Fox and Durnford, 2002), are
not valid. In order to analyze this data, this research combines the analysis presented by
Fox et al. (2001) on finite stream width effects (i.e., the FDD analytical solution) and the
STRMAQ package (Fox and Durnford, 2002) to develop a solution capable of addressing
all critical slough/aquifer interaction conditions. Using this improved STRMAQ
package, predicted drawdown is individually matched to the observed drawdown in
observation wells A15ES and B2ES using a trial and error approach.
E