2015-10-30_HYDROLOGY - M1982147

• Permit No: M1982147
• IBM Index Class Name: HYDROLOGY
• Doc Date: 10/30/2015
• Doc Name: Amendment to permit
• From: DNR Water Resources
• To: DRMS
• Email Name: TOD
• Media Type: D
• Archive: No

Table 1
Derivation of Net Evaporation and Stream Depletion from Nyholt-Mann Lake
Adams County Regional Park
Month
Evaporation
Distribution
Gross Lake
Evaporation
(inches)
Effective
Precipitation , Precipitation
(inches) (inches)
Net
Evaporation
(inches)
Net evaporation
Nyholt-Mann Lake
(ac -ft)
Stream Depletion to
South Platte River
(ac -ft)
Delivery Required at
Metro Wastewater @
5.5% Transit Loss
(ac -ft)
(1)
(2)
(3)
(4)
(5)
(6)
(7)
(8)
(9)
Jan
3.0%
1.35
0.46
0.32
1.03
4.4
4.7
5.0
Feb
3.5%
1.58
0.39
0.27
1.31
5.6
5.7
6.0
Mar
5.5%
9.0%
2.48
i
4.05
1.25
1.72
0.88
1.20
1.60
2.85
6.9
12.2
6.9
7.3
-
Apr
11.8
12.5
May
12.0%
5.40 j
2.47
1.73
3.67
15.8
15.3
16.2
Jun
14.5%
6.53
1.67
1.17
5.36
23.0
22.0
23.3
Jul
15.0%
6.75
1.60
1.12
5.63
24.2
23.6
25.0
Aug
13.5% T
6.08
1.61
1.13
4.95
21.2
21.1
22.3
Sep
10.0%
4.50
1.09
0.76
3.74
16.1
16.4
17.4
Oct
7.0%
3.15
0.83
0.58
2.57
11.0
11.6
12.3
Nov
4.0%
1.80
0.88
0.62
1.18
5.1
5.9
6.2
Dec
3.0%
1.35
0.50
0.35
1.00
4.3
4.8
5.1
Total
100.0% ,
45.02
14.47
10.13
34.89
149.8
149.8
158.6
Column explanation:
2) Monthly distribution from "Guidelines for Substitute Water Supply and Augmentation Plans for Sand and Gravel Pits Submitted to the State
Engineer Pursuant to Senate Bill 89-120 and 93-260" for sites below 6500 feet msl.
3) Annual value interpolated from "Evaporation Atlas for the Contiguous 48 United States", NOAA Technical Report NWS33 Map 3, 1951-1980
average and distributed using factors in Column 2.
4) Brighton weather station data, 1973 to 2003 average.
5) Column 4 x 70% per State Engineer's guidelines described above.
6) Column 3 - Column 5.
7) Column 6 x 51.5 acres / 12 inches per foot. The water surface area totals 65.5 acres but 51.5 acres were exposed after December 31, 1980.
8) Lagged depletion based on Glover Analysis using Net Evaporation (Column 7), aquifer transmissivity of 100,000 gpd/ft, specific yield of 0.20, and
distance from lake to river of 140 feet.
9) Column 8 - (1 - 0.055). Distance from Metro Wastewater to Nyholt-Mann Lake is 11 miles.
Helton & Williamsen, P.C.
8/18/2015, EvapGrassWB 2012 swsp.xls, Exhibit D, taw