2012-08-01_HYDROLOGY - M1980149

• Permit No: M1980149
• IBM Index Class Name: Hydrology
• Doc Date: 8/1/2012
• Doc Name: SUBSTITUTE WATER SUPPLY PLAN
• From: DWR
• To: CLEAR WATER SOLUTIONS
• Email Name: PSH
• Media Type: D
• Archive: No

Location
X (ft)
W (ft)
T (gpd /ft)
S.Y.
Cell
2,083
9,403
14,483
0.2
CeII 2
843
9,246
10,338
0.2
Cell
2,320
10,427
14,483
0.2
Cell 4
889
7,590
10,338
0.2
Cell
2,725
8,954
15,414
0.2
Cell 6
2,032
8,924
13,775
0.2
Cell
1,032
8,902
12,264
0.2
Cell8
306
8,812
9,364
0.2
Cell 9
495
8,772
8,444
0.2
CeII 10
1,015
8,979
9,540
0.2
CeII 11
390
8,181
8,042
0.2
Cell 12
782
9,159
9,527
0.2
SW Services Pump
2,083
9,403
14,483
0.2
Ms. Michelle L. Hatcher
Hokestra SWSP
July 30, 2012
Page 3 of 7
Weld County uses ground water from the southwestern reclaimed cell (Cell 1) to irrigate
landscape W the Weld County Southwest Service Center. Weld County conducted a field survey
on February 7, 2008 and reported that the landscaped area consists of 0.15 acres of blue grass
and 5.5 acres of native grass. This area will be irrigated using water pumped from CeII 1 during the
growing season of April through October. According to a Modified Blaney - Criddle analysis, the
potential crop consumptive use for the 0.15 acres of blue grass is 0.30 acre -feet, and the potential
crop consumptive use for the 5.5 acres of native grass is 9.4 acre -feet. Since the irrigation occurs
directly around the reclaimed cell, the plan assumes that irrigation return flows will return to the
river in the same timing as the depletions.
The total consumptive use of ground water associated with the Hokestra Pit is estimated
to be 153.5 acre -feet, consisting of 143.9 acre -feet of evaporation loss from 56.4 acres of
post -80 exposed surface area and 9.6 acre -feet of water used for irrigation at the SWSC.
The depletions from evaporation losses were lagged to the Saint Vrain River using a Glover
analysis. The following aquifer parameters were used in the model:
X - Distance from well to river, measured from the centroid of the exposed area
W - Distance from the aquifer boundary through the well to the river channel
T - Transmissivity of the alluvial aquifer between the well and the river (source: Tgrid0309 GIS layer from SPDSS)
S.Y - Specific Yield
The total lagged stream depletions from the operation of the Hokestra Pit during this plan
period are 146.9 acre -feet. The monthly distribution of these depletions is summarized on the
attached Table 16.
Replacements
The sources of replacement water are 3.75 shares in the Rural Ditch Company owned
by the County, storage of excess credits of these shares in Varra Companies' 112 Pit, and a
onetime lease of Rural Ditch water from Varra Companies.