Big Chino Ranch Project
Citizens Water Advocacy Group (CWAG) Briefing Report & Questions
The City of Prescott water service area is located within the Prescott Active Management Area (AMA) and also extends into the Town of Chino Valley, the Reservation of the Yavapai-Prescott Indian Tribe, and some surrounding unincorporated areas of Yavapai County. The City of Prescott is the only designated water provider in the AMA with a 100-year Assured Water Supply.
The City’s current water system is complex, with 6 water production wells, 31 storage tanks (28 million gallons total), 40 pump stations, and 47 different pressure zones. Since 1948, the main source of water supply has been from a well field located within the Town of Chino Valley in the Little Chino Subbasin of the Prescott AMA, approximately 15 miles north of the Prescott City limits. Water is transported into the City via three transmission lines, including a 36" high-pressure main. Approximately 8,500 acre-ft of water were produced in 2004 at the well field.
The population served by the City’s water system is approximately 40,000 representing 19,000 customer accounts. The 2025 population is projected to be 55,000. The growth rate has averaged 2% - 3% per year.
In January 1999, the Arizona Department of Water Resources declared that the Prescott AMA was no longer at safe-yield. This triggered full implementation of the Assured Water Supply Rules, requiring that only renewable or imported water supplies from outside the Prescott AMA be utilized for new subdivisions within the AMA.
The City of Prescott, in partnership with the Town of Prescott Valley, in December 2004 purchased lands north of the Prescott Active Management Area in the Big Chino Subbasin of the Verde River Groundwater Basin referred to as the Big Chino Ranch (BCR). Section 45-555, Arizona Revised Statutes, allows for the transportation of groundwater by Prescott AMA municipalities from the Big Chino Subbasin for use inside the AMA. The Big Chino Ranch is comprised of 4,582.1 acres of deeded lands and 1,948.6 acres of Arizona State Land within Yavapai County located in Townships 19 and 20 North-Range 4 West and Township 20 North-Range 5 West, G&SRB&M.
The City of Prescott is a 55% partner and the Town of Prescott Valley a 45% partner in water from the BCR. The communities intend to develop the infrastructure necessary to transport groundwater from the Big Chino Subbasin for use inside the Prescott AMA by July 2009.
The Big Chino Ranch Project is comprised of four major tasks:
- BCR environmental assessment and remediation
- Well field development and Ranch Management Plan
- Transmission pipeline and associated storage & pumping infrastructure
- Installation of monitoring wells to gauge the potential impacts of the withdrawal and transportation of groundwater from the Big Chino Ranch
Design and construction of the BCR pipeline is being phased as follows:
- Phase I
Conceptual Design & Preliminary Cost Estimates
- Phase II
Preliminary and Final Design; Construction Documents; Cost Estimates; Environmental and other Permitting; Right-of-way Mapping
- Phase III
Advertisement for Construction Bids and Evaluation for Award
- Phase IV
Construction, including Project Management, Coordination, and Communications
The 30 mile pipeline from the BCR Ranch to Paulden and from Paulden to Chino Valley, Arizona, is currently sized to transport up to 12,400 acre-feet of groundwater per year.
For more information contact Craig McConnell, Project Manager for the Big Chino Ranch for the City of Prescott at:
201 S Cortez Street
Prescott AZ 86303