PUB00053

• Year: 1999
• Title: Metropolitian Water Supply Investigation Final Report
• Author: Hydrosphere Resource Consultants
• Description: Metropolitian Water Supply Investigation Final Report
• Publications - Doc Type: Water Resource Studies

Metropolitan Water Supply Investigation

MWSI Results

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heavily upon storage because most of the remaining native supply occurs only during
periods of high flows,

This source constitutes approximately 18% of the South Platte Basin's existing municipal
water supply, Future opportunities for additional development of native South Platte
flows will require some form of additional storage. Storage opportunities include new
surface storage reservoirs, enlargements of existing surface reservoirs, reallocation of
space in flood control reservoirs and "groundwater storage via recharge.

3.1.4.2. In-Basin Agricultural Transfers

This source includes water supplies derived from acquisition of water supplies originally
used for irrigation purposes within the South Platte Basin, As Front Range cities began
to develop, they typically acquired irrigation rights that diverted within or adjacent to
their urban service areas, More recently, municipal providers have acquired irrigation
rights on a larger scale, often changing the location of use of those rights by several
"miles, As an example, over 30,000 acre feet of irrigation rights in the South Park area of
the Upper South Platte Basin have been acquired and changed to municipal use by metro
Denver area providers, principally Aurora and Thornton. As another example, the
Colorado-Big Thompson project, completed in the 1950's, originally provided
supplemental water supplies primarily to agricultural users within the South Platte Basin.
Over the last 40 years, a significant amount of this supply has been acquired and changed
to municipal use in accordance with the policies and rules of the Northern Colorado
Water Conservancy District.

This source constitutes approximately 25% of South Platte Basin's existing municipal
water supply. Future opportunities for additional in-basin agricultural transfers largely
exist in the Northern Region, which is where most of the remaining irrigated agriculture
is located,

3.1.4.3. Trans-Basin Imports

This source includes supplies imported from the Colorado, Arkansas and North Platte
River basins, Transbasin import of water into the South Platte Basin for municipal
purposes began in 1936 with the completion of the Moffat TUilllel. Existing transbasin
diversion projects providing municipal and industrial supplies to the South Platte Basin
include the Colorado-Big Thompson and Windy Gap projects; Denver's Roberts Tunnel
and Moffat Tunnel collection systems; Aurora's diversions from the Homestake, Twin
Lakes and Busk-Ivahoe projects via the Otero pump station; the Grand River Ditch: the
Berthoud Pass Ditch: the Boreas Pass Ditch: and the Vidler tunnel. Transbasin diversions
from the Colorado basin into the South Platte Basin currently average about 430,000
acre-feet per year. About 38% of this amount, or about 162,000 acre-feet, is diverted for
municipal and industrial purposes within the metro Denver area,

Imported water currently provides approximately 30% of the South Platte Basin's

municipal water supply, Supplies from this source are expected to increase in the future

through more intensive use of existing water rights and facilities, New storage capacity,

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Prepared for the Colorado Water Conservation Board, Colorado Department of Natural Resources by
Hydrosphere Resource Consultants, 1002 Walnut Street, Suite 200, Boulder, CO 80302