WSPC12488

• File Number: 8283.200
• Description: Colorado River Computer Models - Colorado River Decision Support System
• State: CO
• Basin: Colorado Mainstem
• Water Division: 5
• Date: 1/1/3000
• Author: Unknown
• Title: Climax Mine and Mill Major Direct Flow Water Rights Information - RE-CRDSS - Date Unknown
• Water Supply Pro - Doc Type: Report/Study

OJOJ.:,,6

associated with this time series. Depletions attributable to the Eagle and Arkansas River imports are relatively small
and can be neglected in the CRDSS modeling.
C.8.6.4 Henderson Mine and Mill (WDID 511070)
The Henderson Mine is also owned by the Climax Molybdenum Company. It is an underground mine located in the
South Platte drainage basin near Berthoud Pass. The mine was opened in 1977 and it has been operated almost
continuously since that date. Water is pumped from the mine to maintain dry working conditions and this water is
discharged into a tributary of Clear Creek. Because the mine and mine water discharge is located in the South Platte
River basin, this operation has no effect on streamflows in the Colorado River basin. Ore from the mine is hauled
from the mine through a 12-mile underground train tunnel to the Henderson Mill, located in the Ute Creek drainage
basin, a tributary of the Williams Fork River, upstream of Williams Fork Reservoir. The milling process employed
at the Henderson Mill is generally identical to the process used at the Climax Mine, based on flotation of
molybdenum concentrate and slurry transport of tailing for deposition in large tailing ponds. Water is used and
reused in the milling process through an elaborate system of pumping stations, pipelines, reservoirs, tanks, and a
single large tailing pond. Consumptive use of water is primarily associated with evaporation from the tailing pond
and reservoirs, together with the consumption of water trapped within the deposited tailing sands. Historic stream
depletions averaged about 2,200 acre-feet during the CRDSS study period of 1975 through 1991, with a maximum
of about 3,700 acre-feet in 1980.
Water to replace the system losses and provide the necessary process water is diverted from Ute Creek, a small
tributary of the Williams Fork, at several intake points. Additional water is diverted from the mainstem of the
Williams Fork River at the Williams Fork pump station on an as-needed basis. The pump station capacity is 8.8 cfs.
The Henderson Mill is a closed circuit, non-discharging facility. Accordingly, the diversion effIciency is 100 percent
and all water that is diverted into the industrial process system is ultimately consumed. Storage facilities at the mill
include Ute Creek Reservoir (100 acre-feet) and East Branch Reservoir (2,000 acre-feet). The tailing pond itself is
capable of storing several thousand acre-feet of additional water which can be used and re-used in the milling
processes.
Water rights used at the Henderson Mill include the Henderson Mine Water System, the Ute Park storage right, and
the Cabin-Meadow Creek water rights agreement. The Henderson Mine Water System water right includes a
number of senior irrigation water rights that were changed in Case No. W-528 to allow industrial use. The annual
volume of water that may be diverted into the mill system and consumptively used pursuant to this right is limited to
704 acre-feet per year and the diversions are limited to the spring and summer period when the Shoshone call is not
in effect. The Ute Park storage right is absolute in the amount of 2,100 acre-feet and conditional for an additional
3,900 acre-feet. This water right is junior to Denver's Williams Fork Reservoir, so the right may only be exercised
during years in which Williams Fork Reservoir fIlls. The Cabin-Meadow Creek water rights agreement is a complex
agreement among the Climax Molybdenum Company, the Denver Water Board, and the city of Englewood (see
separate documentation). In the early 1970's, these parties jointly constructed the Cabin Meadow Creek Project, a
diversion and storage project in the Fraser River basin. The Henderson Mill does not directly make use of the Fraser
basin water, but instead diverts water from the Williams Fork basin pursuant to a replacement agreement with
Denver. Pursuant to the agreement, Henderson is entitled to divert up to 3,000 acre-feet per year from Ute Creek
and/or the Williams Fork River on a year-round basis as necessary to the meet the milling demand. To the extent
that Henderson requires water during periods when Denver would otherwise be exercising its senior rights at its
Williams Fork Collection system, the Henderson water in Meadow Creek Reservoir is credited to Denver's account
in the reservoir in an amount equivalent to the amount of out-of-priority diversion by Henderson. Also in accordance
with the Agreements, at times when the Shoshone call is in effect, replacement releases are made by Denver from
Williams Fork Reservoir for the benefIt of Henderson. This Henderson replacement account in Williams Fork
Reservoir contains up to 2,200 acre-feet.
SpecifIc water rights used at the Henderson Mill include the following:
Name Amount Adjudication
(acre-feet) Date
704 08-03-1911
2,100 09-08-1954
3,000 Uses Denver Water
Rights
In order to simplify the CRDSS modeling effort, it is recommended that the Henderson Mill diversions be modeled
as a single diversion at the Williams Fork Pump Station. This aggregated node should be in the amount of 8.8 cfs
(the capacity of the pump station) with a recommended administration number of 31359.00001, a value that is

Henderson Mine ~ C:lter Sy~tem
Ute Park Reservoir Right
Cabin-Meadow Creek Agreement

Appropriation
Date
Varies

Admin.
No.

Varies

38236.00000

Varies

Varies