SPDSS_Task59-2_Irrigation Water Requirements at Climate Stations

• Title: SPDSS Task 59.2 - Irrigation Water Requirements at Climate Stations
• Description: SPDSS Task 59.2 – This memorandum presents the approach and results from the completion of the following Task 59 subtask: Using calibrated crop coefficients, estimate the irrigation water requirement for common crops grown at the key climate stations identified in Task 53.
• Decision Support - Doc Type: Task Memorandum
• Date: 3/24/2005
• DSS Category: Consumptive Use
• DSS: South Platte
• Basin: South Platte
• Contract/PO #: C153954
• 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

Table 2
Average Annual Irrigation Water Requirement in Feet
1950 through 2003

Climate Station Station
ID Water
District
Alfalfa Corn
Grain Dry
Beans Grass
Pasture Small
Grains Sugar
Beets
Hi h Altit ude Re io n
Allenspark 1 NW (combined) 185 5 - - - 1.69 - -
Antero Reservoir 263 23 - - - 1.74 - -
Bailey 454 80 - - - 1.86 - -
Cheesman 1528 80 - - - 2.07 - -
Estes Park (combined) 2761 4 - - - 1.99 - -
Evergreen (combined) 2790 9 - - - 1.92 - -
Georgetown 3261 7 - - - 1.94 - -
Red Feather Lakes (combined) 6921 3 - - - 1.80 - -
Walden 8756 47 - - - 1.88 - -
High Altitude Region Average - - - 1.88 - -
High Altitude Region Maximum % Difference - - - 10% - -
U er Pla ins Re io n
Boulder 848 6 2.07 1.35 0.97 2.23 1.07 1.55
Briggsdale 945 1 1.87 1.23 0.88 2.04 1.18 1.35
Byers 5 ENE 1179 1 1.94 1.30 0.94 2.13 1.19 1.44
Castle Rock 1401 8 1.60 - - 1.76 1.05 -
Denver WSFO AP (Stapleton) 2220 2 2.12 1.38 1.00 2.26 1.20 1.60
Fort Collins 3005 3 1.93 1.29 0.93 2.07 1.15 1.49
Fort Morgan 3038 1 2.23 1.45 1.06 2.36 1.28 1.69
Greeley UNC (combined) 3553 3 2.18 1.45 1.07 2.34 1.24 1.66
Lakewood (combined) 4762 8 1.95 - - 2.12 1.17 -
Longmont 2 ESE 5116 5 2.05 1.38 1.02 2.19 1.26 1.56
Parker 2 N (combined) 6323 8 1.75 - - 1.95 1.11 -
U er Plains Re ion Avera e 1.97 1.35 0.98 2.13 1.17 1.54
Upper Plains Region Maximum % Difference 19% 9% 11% 17% 10% 12%
Lower Pla ins Re io n
Akron 4 E (combined) 109 65' 2.06 1.36 0.95 2.27 1.26 1.56
Julesburg 4413 64 2.35 1.51 1.05 2.60 1.29 1.76
New Raymer 5922 64 1.97 1.29 0.90 2.19 1.23 1.46
New Raymer 21 N (combined) 5934 64 1.76 1.18 0.84 1.99 1.20 1.32
Sedgwick 5 S (combined) 7515 64 2.28 1.48 1.02 2.51 1.24 1.73
Sterling 7950 64 2.25 1.45 1.03 2.46 1.30 1.69
Lower Plains Region Average 2.11 1.38 0.97 2.34 1.25 1.59
Lower Plains Region Maximum % Difference 17% 14% 13% 15% 4% 17%
Note: i Akron 4 E (combined) is located in Water District 65, and will use the Lower Plains Calibrated Coefficients.
Figures 2 through 7 at the end of this memo show the average annual IWR over the 1950
through 2003 period for each crop type. The maximum percent difference for a given crop type
across climate stations within the same regions ranges from 4% to 19%. The largest percent
difference was found with alfalfa in the Upper Plains Region where a 19% difference equates to
approximately .37 feet on an average annual basis. As shown, IWR is generally highest in the
Lower Plains Region for all crop types and lowest in the High Altitude Region for grass pasture.
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