WSP09401

• File Number: 8056
• Description: Drought Preparedness
• State: CO
• Basin: Statewide
• Date: 8/28/1986
• Author: CDM
• Title: Phase I - Drought Study - City of Loveland Raw Water Supply System
• Water Supply Pro - Doc Type: Report/Study

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or in planning to meet future water needs. Future populations and water

demands, however, are subject to many factors which cannot be accurately

forecast; consequently, this study examined a range of possible growth

rates over the next three decades. The reliability of the City's water

supply (including the anticipated gain in future water supplies due to

development) was estimated for each of six planning scenarios; these

scenarios correspond to projected levels of development in the years 2000

and 2015 under low, moderate and high growth rates.

Total Vater Supply Available to City - The physical availability of water

in the CBT and Vindy Gap projects as well as native streamflow derived from

the Big Thompson watershed was determined. It was necessary to determine

what portion of the physical supply could be diverted for City use under

Colorado Vater Law and the management policies of the NCVCD and HS-NCVCD.

For the Big Thompson River direct-flow rights, this determination entails

allocation of available water in accordance with water rights and the terms

of the Loveland Transfer Decree (Vater Case Number 82-CV-202A). The

availability of CBT water during any year will be partially dependent upon

the annual "quota" set by the NC1lCD; the quota defines the percentage of an

owners shares which may be delivered in a given year.

Evaluation of System Yield - The results of the previous steps produced a
1000-year monthly record of the total quantity of water theoretically
available to the City. System yield and reliability were determined by
using this 1000-year record of available water as inflow to the City water
treatment plant. For each month, the City demand was compared to the
available supply. Any excess water from rights granted in the Transfer
Decree was stored in Loveland's existing Green Ridge Glade reservoir for
future use subject to capacity, operational and legal constraints.

If the demand exceeded the available supply (including storage) in any

month, the shortage was recorded as a "deficit" and that month was

identified as a "failure", i.e., a failure to meet the specified demand.

The reliability of the system was measured by the probability of failure.

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