PROJ02008

• Contract/PO #: FS0073FX
• Contractor Name: Lamar, City of
• Contract Type: Grant
• Water District: 0
• Loan Projects - Doc Type: Feasibility Study

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secondary water systems are installed in phases and some upsizing of pipe may be
required to accommodate future project phasing.

The irrigation pump stations must be designed to provide consistent pressure over a
wide variation in flow. Pump stations with variable frequency drives (also know as VFD
pumps) are typically utilized because of the operational flexibility that VFD stations
afford.

A typical system pumping water from a storage pond will include a pond intake screen,
intake pipe, wet well, multi-pump prefabricated pump station, and automatic self-
cleaning filter. Generally, a two or three pump system is adequate. However, three or
four main pumps are provided on large secondary water systems, or where redundant
pumps are required to meet specific owner requirements or to ensure adequate backup
in case of pump failure or to take a pump off line for minor repairs.

Where possible, the existing diversion structure and headgate that has historically been
in place to control the delivery of water for agricultural use can be maintained and kept in
place for the secondary water system as well. However, frequently the existing diversion
does not work with the site layout and grading. In these instances, a new diversion
structure, headgate, flow measurement structure, and diversion ditch or pipe may be
required. In some cases, pumps are required to lift water from the diversion structure to
a storage pond. The lift pumps must be capable of diverting water to the storage pond
within the constraints imposed by the ditch company. For example, the lift pumps may
have to be designed to pump at the same delivery flow rate that historically was used
with the gravity diversion system.

Socio-Economic Considerations

The percentage of the population not earning an income through employment may be a
consideration when it comes to establishing initial water rates for the secondary system.
The bottom line would appear to be that, given the above (Table 1) and other socio-
economic characteristics of Lamar discussed below, the combined rate of potable and
secondary water service should not exceed the current cost of potable water use (Le.,
for both indoor and outdoor use) borne by community residents.

Ideally, the combined rate for potable and secondary water should be initiated at a
degree less than the current cost of potable water. This would ensure that any of the
socio-economic characteristics mentioned for Lamar that could conceivably contribute to
a lack of success in the project would be minimized. Some comments are made in a
later section regarding how the project might be phased in to minimize the impact on
residents having fixed income, or income significantly below the median.

Many rural communities in the Rocky Mountain region are beginning to grow after
several years of population decline. The City of Lamar would appear to be no exception.
The City of Lamar has excellent potential for growth, since it is located at the intersection
of two important interstate transportation arteries. It has good schools, including one of
the few community colleges in the High Plains.

An important question to ask is whether or not the development of a secondary water
system for Lamar represents an affordable endeavor. All capital improvements for a
Aqua Engineering, Inc.
and Colorado State University Secondary Supply Feasibility Study
May 19, 2004 -5-