SPDSS_Task7-2_WellUseWellAugmentationPlans

• Title: SPDSS Task 7.2 - Well Use and Well Augmentation Plans
• Description: This memorandum and associated appendices characterizes the 20 largest well augmentation plans and develops recommendations for representing well use and augmentation in SPDSS modeling efforts.
• Decision Support - Doc Type: Task Memorandum
• Date: 12/14/2007
• DSS Category: Groundwater
• DSS: South Platte
• Basin: South Platte
• Contract/PO #: C153953
• Grant Type: Non-Reimbursable
• Bill Number: SB01-157, HB02-1152, SB03-110, HB04-1221, SB05-084, HB06-1313, SB07-122
• Prepared By: Leonard Rice Engineering

ditch loss at those times. Per the W-2969 decree, lagged accretions to the South Platte River from
diversions to recharge are accounted via the Stream Depletion Factor (SDF) method. Most of the
wells are metered and pump records are submitted to the Division of Water Resources with the
monthly accounting. Out-of-priority lagged well depletions are administered with a common
priority date at multiple locations below the Lower Platte & Beaver Canal headgate.
Recommendations
Recommendations for representing the Lower Platte & Beaver Co. augmentation plan in the
initial development of the SPDSS StateMod Water Resources Planning Model input files are
presented below based on review of the decree and interviews with canal company personnel and
Division 1 personnel.
Augmentation Plan Demands
To represent pumping for the entire SPDSS study period (1950 to present), well pumping to
supply irrigated lands should be estimated by the consumptive use algorithm in StateCU and
StateMod, to meet the irrigation water requirement less simulated surface water deliveries (if
applicable). Lagged well depletions affect river flows based on timing and location factors
defined in StateMod input files. Lagged depletions and the supplies used to meet those
obligations should be accounted in three Lower Platte & Beaver Well Depletions Plan structure,
corresponding with administration of the augmentation plan in three reaches:
1. Above North Sterling Canal (ID 0102535_1)
2. Below North Sterling Canal and Above Prewitt Inlet Canal (ID 0102535_2)
3. Below Prewitt Inlet Canal (ID 0102535_3)
Wells associated with the Lower Platte & Beaver plan should be assigned to the various
administration reaches based on spatial location.
Augmentation Plan Supplies
Various sources are typically available to supply water to replace lagged well depletions. The
sources and the structures related to the Lower Platte & Beaver augmentation plan recommended
for inclusion in the SPDSS model are summarized in Table 2. Augmentation supplies are as
follows:
Recharge rights from the river for the Lower Platte & Beaver Canal augmentation plan
are summarized in Table 3.
Recharge well rights and augmentation well rights are summarized in Table 4.
Model operations to supply well depletions (stored under plan IDs 0102535_1, 0102535_2, and
0102535_3) are discussed in the augmentation plan operations section.
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