2015-08-28_HYDROLOGY - M19772572

• Permit No: M1977572
• IBM Index Class Name: HYDROLOGY
• Doc Date: 8/28/2015
• Doc Name: Substitute Water Supply Plan
• From: DWR
• To: DRMS
• Email Name: AME
• Media Type: D
• Archive: No

Table 1
City of Lamar
Lamar North Gateway Park Pond Nos. 1, 2 and 3
Derivation of Monthly Evaporation Rates
Month
(1)
Monthly
Distribution
N
(2)
Gross
Evaporation Rate
(in)
(3)
Average
Precipitation
(in)
(4)
Effective
Precipitation
(in)
(5)
Net
Evaporation Rate
(ft)
(6)
Pond
Evaporation
(af)
(7)
January
3.0
1.80
0.38
0.27
0.13
3.02
February
3.5
2.10
0.47
0.33
0.15
3.48
March
5.5
3.30
_0.86
0.60
0.22
5.10
April
9.0
5.40
1.45
1.01
0.37
8.58
May
12.0
7.20
2.42
1_69
0.46
10.67
June
14.5
8.70
_
2.24
1.56
0.59
13.69
July
15.0
__ 9.00
2_30
1.61
0.62
14.38
_ _
August
13.5
8.10
2.17
1_52 _
0.55
12.76
September
10.0
6.00
1.19
0.84
_ 0.43 _
9.98
October
7.0
4.20
0.88
0.62
0.30
6.96
November
4.0
_
2.40
0.57
0.40
0.17
3.94
December
3.0
1.80
0.44
0.31
0.12
1 2.78
Total
100.0
60.00
15.37
10.76
4.11 1
95.35
Explanation of Columns:
2) Monthly Distribution from"General Guidelines for Substitute Water Supply for Sand and Gravel Pits" (Updated April 1, 2011)
3) Interpolated from "Evaporation Atlas for the Contiguous 48 United States", NOAA Technical Report NWS 33 Map 3,
U.S. Department of Commerce, June 1982.
4) Average Precipitation from Colorado Climate Center for Lamar Climate Station No. 54770 for 1900-1999.
5) Column 4 X 70 percent.
6) Column 3 -Column 5/12.
7) Column 6 X 23.2 acres.
L1001\Table 1
Helton & Williamsen, P.C.