SPDSS_Task5_KeyStructure_RiversideIrrigation

• Title: SPDSS Task 5 - Key Structure, Riverside Irrigation System
• Description: The Riverside Irrigation System has been identified as a key structure for the South Platte Decision Support System ‎(SPDSS)‎ consumptive use and surface water modeling efforts. The purpose of this Task 5 memorandum is to document physical, legal, and operational aspects of those key structures identified.
• Decision Support - Doc Type: Task Memorandum
• Date: 8/10/2004
• DSS Category: Surface Water
• DSS: South Platte
• Basin: South Platte
• Contract/PO #: C153954
• Grant Type: Non-Reimbursable
• Bill Number: SB01-157, HB02-1152, SB03-110, HB04-1221, SB05-084, HB06-1313, SB07-122
• Prepared By: Leonard Rice Engineering

1) Riverside Inlet Canal (Structure ID 0100503)
The Riverside Inlet Canal headgate is located on the north side of the South Platte River and is
the only inlet to the reservoir. The canal travels in an east-southeastern direction paralleling the
South Platte River and terminates at the reservoir. The diversion structure for the unlined canal
on the South Platte River currently consists of Obermeyer® gates, which were constructed in
2000. The inlet canal has a shared headgate with Riverside Ditch (not part of the System),
whereby the ditch conveys water to Illinois Ditch.
Length: Approximately 10 miles
Capacity: The capacity of Riverside Inlet Canal is 1000 cfs.
Measurement Device: Diversion measurements are made using a weir with a clock and recorder
located just upstream of the reservoir. Diversion records for Riverside Inlet Canal,
Riverside Ditch and Illinois Ditch are recorded separately. The measurement device is
maintained and rated by the State and the Water Commissioner is responsible for
collecting the records.
Conveyance Efficiency: Riverside Inlet Canal experiences losses of approximately 25%,
although no studies have been performed on conveyance losses.
Return Flow Locations: Seepage losses generally accrue to the South Platte River. Seepage
rates do not generally vary due to almost year round diversions.
HydroBase Data: Historic records of diversions into storage and direct flow diversions for the
District are available in HydroBase under the Riverside Canal structure and are generally
available from 1950 through 2003. Total historic diversions under the Riverside Canal
structure average 47,300 acre-feet per year and include diversions into storage and direct
flow diversions for irrigation. Diversion records are reported to the Water Commissioner
in Water District 1. Riverside Inlet Canal has a shared headgate with Riverside Ditch,
with the diversion records for Riverside Ditch and Illinois Ditch recorded separately from
the inlet canal.
2) Riverside Reservoir System
Riverside Reservoir is an off-channel storage facility located in Water District 1 approximately
20 miles downstream from the Water District boundary on the north side of the South Platte
River. Riverside Reservoir is situated due north of the Town of Masters. The reservoir was
completed around 1907 and is used for irrigation, augmentation and recreation.
A single 4.5 mile earthen embankment with concrete facing impounds the reservoir along the
south and southeast sides of the reservoir. The reservoir does not have a spillway, although the
Company is currently in discussions with the state regarding spillway designs. The reservoir's
outlet works are located on the south side of the reservoir and consist of a set of guard and
regulating gates that have a capacity of 370 cfs. The Riverside Canal delivers irrigation water to
System lands and has an estimated conveyance loss of 25%.
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