PROJ00106

• Contract/PO #: C153494
• Contractor Name: Loveland, City of
• Water District: 0
• County: Larimer
• Bill Number: XB 99-999
• Loan Projects - Doc Type: Feasibility Study

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The most frequent mode of operation utilizes the Olympus Tunnel and CHFC in
order to route water through both the Olympus and Big Thompson Power Plants
(BTPP). Typically, the Dille Tunnel is unused since transmission of water
through the Dille Tunnel would bypass the Olympus Plant and therefore
decrease the total power output from the CBT facilities. When the demand
for CBT/Windy Gap water within the Big Thompson watershed is not sufficient
to fully utilize the BTPP and water is available in the Big Thompson,
diversions of Big Thompson River water are made through the Dille Tunnel to
increase the flow through the BTPP.

3.2.2 OPERATIONAL FACTORS AFFECTING STORAGE OF CITY-OWNED WATER

As noted earlier, delivery to Green Ridge Glade Reservoir of City-owned

water rights on the Big Thompson River is currently possible only through

use of the CHFC. This was made possible by obtaining the Dille Tunnel as

an alternate point of diversion in the Transfer Decree. Use of these

facilities to deliver water to Green Ridge Glade, however, may be in

competition with the NCWCD's mission when:

1. The CHFC is flowing at its maximum capacity in order to fill
Horsetooth Reservoir and/or deliver CBT and/or Windy Gap water to
users north of Loveland. The maximum capacity of the canal in the
vicinity of the turnout to Green Ridge Glade is 550 cfs; south of
the Big Thompson River the maximum capacity is 930 cfs.

2. Diversion of skim water through Dille Tunnel decreases the amount
of water that would otherwise pass through the Olympus Power Plant;
this reduces the hydroelectric output of the system and is referred
to as "power interference".

3. Delivery of water to Green Ridge Glade reduces the quantity of skim
water that would otherwise pass through the BTPP (e.g., power
interference) .

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Historic and projected discharge records for the Dille Tunnel and Charles
Hansen Feeder Canal were examined to estimate the impact of these factors
on the quantity of water diverted by the City to storage.

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