2013-10-04_GENERAL DOCUMENTS - M1999120

• Permit No: M1999120
• IBM Index Class Name: GENERAL DOCUMENTS
• Doc Date: 10/4/2013
• Doc Name: Cause of Damage
• From: Ross Bachofer and Gancer Lujan & Assoc
• To: DRMS
• Email Name: ECS
• Media Type: D
• Archive: No

(:ANSE'14 LUJAN & ASSO CIA'i ES
Hydrogeologiral and Environmental Consultants
Evaluation of U.S.G. S. and CDWR Stream Gauge Records on the South Platte River
in the Vicinity of the Bachofer Property and Fort Lupton Area
Discharge data from the Fort Lupton Gauging Station on the South Platter River were
obtained online from the USGS National Water Information System. The station is located
on the South Platte River on CR 18 '/Z mile north of the Bachofer property. Data have been
collected intermittently since 1930 to the present. Early data from 1930 to 1957 were
collected from the original station that was located approximately 3 miles upstream from the
present location on CR 18. No data were collected from 1958 to 2002 and the station was
moved to its present location in 2002 (oral comm. Rick Crowfood, USGS), where stream
data have been collected since 2003. Annual peak flows at Fort Lupton Station are shown
below on Figure 2.
Figure 2
Peak Flows at Fort Lupton
South Platte River
Flow data from the missing years, 1958 to 2002 were calculated by using a linear regression
analysis of flow data (2002 to 2012) from the Henderson station located approximately 14
miles upstream from the Fort Lupton station. Peak flows from this station are presented on
Figure 3 below. Data from this station are collected by the Colorado Division of Water
Resources (CDRW) State Engineer's Office and was obtained online.
The results of the regression analysis with the regression equation are shown on Figure 4
and were used to estimate discharge at the Fort Lupton station. Figure 2 shows these
estimated predicted data with a dashed line and hollow symbol marker. In the years
preceding the existence of the present Fort Lupton gauge from 1987 to 1995, Mr. Bachofer
reported that peak flows at the Henderson station exceeding 11,000 cfs on Figure 3, did not
4
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30,000
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Flow data from the missing years, 1958 to 2002 were calculated by using a linear regression
analysis of flow data (2002 to 2012) from the Henderson station located approximately 14
miles upstream from the Fort Lupton station. Peak flows from this station are presented on
Figure 3 below. Data from this station are collected by the Colorado Division of Water
Resources (CDRW) State Engineer's Office and was obtained online.
The results of the regression analysis with the regression equation are shown on Figure 4
and were used to estimate discharge at the Fort Lupton station. Figure 2 shows these
estimated predicted data with a dashed line and hollow symbol marker. In the years
preceding the existence of the present Fort Lupton gauge from 1987 to 1995, Mr. Bachofer
reported that peak flows at the Henderson station exceeding 11,000 cfs on Figure 3, did not
4