2015-08-06_HYDROLOGY - M1996049

• Permit No: M1996049
• IBM Index Class Name: HYDROLOGY
• Doc Date: 8/6/2015
• Doc Name: Substitute Water Supply Plan
• From: Resource Engineering
• To: DRMS
• Email Name: ECS
• Media Type: D
• Archive: No

Mr. Raul Passerini, P.E.
June 24, 2015
Page 5
Change of Use of Famine Creek Ditch and South Rock Creek Ditch:
Historically Famine Creek Ditch and South Rock Creek Ditch irrigated approximately
131.2 acres of pasture grass at the Maryland Creek Ranch property as shown on the attached
Figure A-4. Of this total, 65 acres have been permanently removed from irrigation as shown
on the attached Figure A-5.
The historical consumptive use of the irrigation supply for the 64.96 acres was
quantified based on the average monthly diversion records for the period of 1966 through
2010 for the Famine Creek Ditch and 1965 through 2010 for the South Rock Creek Ditch
(adjusted to the total decreed diversion rate of 5.0 cfs for the Famine Creek Ditch and 8 cfs
for the South Rock Creek Ditch), using the TR -21 Modified Blaney-Criddle Method with
adjustment for elevation. Monthly temperature and precipitation data were taken from
published records for Dillon 1 E station and the Green Mountain Dam station. The ditch loss
from the headgate to the irrigated fields was assumed to be 10 percent and an irrigation
efficiency of 60 percent was used. Water in excess of the irrigation requirement was added to
the soil moisture bank, which was assumed to be 3 feet deep with a water holding capacity of
0.15 inches per inch.
The junior water right in the South Rock Creek Ditch (appropriation July 7, 1935) was
historically called out by the Shoshone Power Plant water right. Historically the water rights
within the Colorado River Basin that are junior to the Shoshone water right have been allowed
to divert without curtailment because of releases of water from the Historic Users Pool
("HUP") in Green Mountain Reservoir. Once the junior water in the South Rock Creek Ditch is
changed for augmentation purposes it will no longer benefit from Green Mountain Reservoir
releases under the HUP. Therefore, for the purpose of this analysis, and based on the
historical call of the Shoshone water right, it was assumed that the South Rock Creek Ditch
was out -of -priority beginning July 1 of each year, and no historical consumptive use credits
for the South Rock Creek Ditch were used for the period of July -November of each year during
the study period.
The average historical consumptive use during the study period from the water rights
in the Famine Creek Ditch and South Rock Creek Ditch for the 65 acres was estimated to be
approximately 61.37 acre-feet, as shown on the attached Table 9 or 0.94 acre-feet per acre.
The historical consumptive use based on average years during the study period was compared
to the historical consumptive use for the dry years for 1977 and 1994. The dry year historical
consumptive use for the 1977 and 1994 was estimated at 1.05 acre-feet per acre, therefore
for the purpose of this SWSP the study period average consumptive use of 0.94 acre-feet per
acre was selected.
Case
priority
Appropriation
Decreed
Water Right Name
Number
Number
Date
Adjudication Date
Amount
(cfs)
Famine Creek Ditch
CA 1277
10
06/01/1882
03/02/1910
5.00
Old Whetstone
CA 1277
22
07/01/1883
03/02/1910
1.00
Sheep Creek Ditch
South Rock Creek
CA 1709
251
07/07/1935
10/26/1937
8.00
Ditch
McKay Ditch
CA 1805
334
10/01/1926
03/10/1952
1 18.67
Change of Use of Famine Creek Ditch and South Rock Creek Ditch:
Historically Famine Creek Ditch and South Rock Creek Ditch irrigated approximately
131.2 acres of pasture grass at the Maryland Creek Ranch property as shown on the attached
Figure A-4. Of this total, 65 acres have been permanently removed from irrigation as shown
on the attached Figure A-5.
The historical consumptive use of the irrigation supply for the 64.96 acres was
quantified based on the average monthly diversion records for the period of 1966 through
2010 for the Famine Creek Ditch and 1965 through 2010 for the South Rock Creek Ditch
(adjusted to the total decreed diversion rate of 5.0 cfs for the Famine Creek Ditch and 8 cfs
for the South Rock Creek Ditch), using the TR -21 Modified Blaney-Criddle Method with
adjustment for elevation. Monthly temperature and precipitation data were taken from
published records for Dillon 1 E station and the Green Mountain Dam station. The ditch loss
from the headgate to the irrigated fields was assumed to be 10 percent and an irrigation
efficiency of 60 percent was used. Water in excess of the irrigation requirement was added to
the soil moisture bank, which was assumed to be 3 feet deep with a water holding capacity of
0.15 inches per inch.
The junior water right in the South Rock Creek Ditch (appropriation July 7, 1935) was
historically called out by the Shoshone Power Plant water right. Historically the water rights
within the Colorado River Basin that are junior to the Shoshone water right have been allowed
to divert without curtailment because of releases of water from the Historic Users Pool
("HUP") in Green Mountain Reservoir. Once the junior water in the South Rock Creek Ditch is
changed for augmentation purposes it will no longer benefit from Green Mountain Reservoir
releases under the HUP. Therefore, for the purpose of this analysis, and based on the
historical call of the Shoshone water right, it was assumed that the South Rock Creek Ditch
was out -of -priority beginning July 1 of each year, and no historical consumptive use credits
for the South Rock Creek Ditch were used for the period of July -November of each year during
the study period.
The average historical consumptive use during the study period from the water rights
in the Famine Creek Ditch and South Rock Creek Ditch for the 65 acres was estimated to be
approximately 61.37 acre-feet, as shown on the attached Table 9 or 0.94 acre-feet per acre.
The historical consumptive use based on average years during the study period was compared
to the historical consumptive use for the dry years for 1977 and 1994. The dry year historical
consumptive use for the 1977 and 1994 was estimated at 1.05 acre-feet per acre, therefore
for the purpose of this SWSP the study period average consumptive use of 0.94 acre-feet per
acre was selected.