Tamarack Modeling Project Documentation

• Description: Tamarack Modeling Project Documentation - DRAFT
• State: CO
• State: NE
• Basin: South Platte
• Water Division: 1
• Title: Tamarack Modeling Project Documentation - DRAFT
• Water Supply Pro - Doc Type: Report/Study

5. Analysis of the Tamarack Recharge Model (Tam001c) was conducted to estimate the
sensitivity of head calibration and river recharge to changes in model parameters such
as hydraulic conductivity and specific yield. The hydraulic conductivity of the River
Floodplain and Paleo- Channel zones are the most sensitive of the aquifer parameters
to changes in head calibration. Changing these two parameters cause the most change
in the head calibration. Changing the specific yield of the Sand Hills zone and the
hydraulic conductivity of the Paleo- Channel zone cause the most change in river
accretions.
Table 3.1 provides a summary of the model versions of the Tamarack Recharge Model.
Table 3.1
Tamarack Recharge Model — Version Summary
•
fa
Version Name
Major Features
1. Main Recharge Area — Includes 7 wells, 2 recharge ponds,
wetlands, artificial stream complex, and sloughs.
Tam001 a
2. Time frame is November 1, 2000 to October 31, 2001.
3. ET varies with depth to groundwater
1. Same area and time frame as Tam001a
2. ET was not allowed to change with depth to groundwater.
Tam001b
First trial where ET was changed directly to negative
recharge.
1. Same area and time frame as Tam001a
2. ET was not allowed to change with depth to groundwater.
Tam001c
Final version where ET was changed to negative recharge
and values reduced by 40 %.
1. Same area and time frame as Tam001a
Tam00ld
2. NO ET included in model
1. Entire Tamarack Project Area — Includes 10 wells, 3
recharge ponds, wetlands, artificial stream complex,
sloughs, and semi -lined ponds.
Tam002a
2. Time frame expanded to cover Project operations from
1997 though October 31, 2002.
3. ET varies with depth to groundwater
1. Same area and time frame as Tam002a
Tam002b
2. ET was not allowed to change with depth to groundwater.
1. Same area, time frame and ET process as Tam002b
Tam002c
2. Neighboring operations were not included in model.
1. Only recharge and pumping from East Recharge Pond #3
and Wells WR -04, WR -09, and WR -10 included in model.
Tam002d
2. Time frame and ET process as Tam002b
3. Neighboring operations were not included in model.
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