C150069 Feasibility Study

• Contract/PO #: C150069
• Contractor Name: Colorado State University
• Contract Type: MOU
• Water District: 0
• Loan Projects - Doc Type: Feasibility Study

ASSESSMENT OF THE BENEFITS AND COSTS OF
PRESSURIZED DUAL WATER SYSTEMS
IN COLORADO

PRINCIPAL INVESTIGATOR:

Colorado Institute for Irrigation Management (CIIM) - Colorado
State University

STUDY TEAM: New Cache La Poudre Irrigating Company
Highland Ditch Company
Northern Colorado Water Conservancy District (NCWCD)
CWR Consulting, LLC
TEC Engineering Company
J-U-B Engineers, Inc.

ENDORSEMENTS: Weld County Commissioners
Weld County Planning Offices
North Weld County Water District
Soldier Canyon Filter Plant (Tri Districts)
St. Vrain and Left Hand Conservancy District

STUDY SUMMARY

In this proposed study, a "dual water system" is defined as the simultaneous but physically separate
provision of pressurized or unpressurized raw irrigation water for outdoor landscaping use to a piece of
property, along with the normal provision of potable water to the same property. One or mOfl~ established
private or nonprofit water purveyors, or a small homeowners association, may be involved in the
provision of raw irrigation water and potable water to said property.

Where observed in other regions of the West, the raw irrigation water service is usually provided by
traditional agricultural irrigation water suppliers (canal companies and irrigation districts), while
municipalities or specially formed water districts provide the potable supply. Where this arrangement
occurs, the agricultural water supplier still performs its role as an irrigation water supplier to farms. Raw
water delivery for landscaping, usually pressurized and un metered, simply becomes a business sideline
for the canal company or irrigation district.

Traditional agricultural water suppliers often enter into this service in localities where urban growth has
rapidly encroached into their service area, resulting in the need to secure greater oversight in how and
under what circumstances their ditch system is converted into other uses. More recently, small
homeowners associations have become involved in raw water delivery, but with very mixed results, due
to their lack of a full-time employed staff to operate and maintain such systems. Dual systems can have
many of the same operation and maintenance requirements of potable systems, and potentially some of
the same liabilities, hence the concern about the use of homeowners associations for this water service.

Recent investigations of "dual systems" in the Rocky Mountain region suggest that the role of canal
companies and irrigation districts in providing pressurized lawn and garden water for subdivisions and
other water users may provide a unique "firewall" for these enterprises in dealing with urban
encroachment into traditional irrigated agriculture service areas. The need to assess the impOltance of this
"firewall" concept, and the need to weigh the overall benefit and cost of various approaches to "dual