Aspen 1997 WCPlan

• Project Type: Water Conservation Plan
• Project Name: City of Aspen Water Conservation Plan
• Title: Water Conservation Element Water Management Plan
• Date: 1/28/1997
• County: Pitkin
• Water Conservation - Doc Type: Complete Plan

townsite, the City operates the Si Johnson Ditch which provides water for street trees as well as.
providing raw water service for irrigation of many privately held parcels. Outside of the City
boundaries, water from the LeonardThomas Reservoir at the treatment plant is used as a supply for
irrigation for the Meadowood common area, as well as the hospital and medium-density housing
developments in the area.

The Holden and Marolt ditch systems are also operated by the City from diversion points on Castle
Creek. These ditch systems provide water for irrigation of the Municipal Golf Course, the Marolt
Open Space, the Red Butte Cemetery, and numerous private properties comprising the Castle Creek
Homeowner Association.

The City also operates the Maroon Creek hydroelectric plant which utilizes water diverted at the
Maroon Creek headgate near the T -Lazy-7 Ranch and returns it to Maroon Creek approximately Y2
mile south of the entrance to the Aspen Highlands Ski area.

1.1 Water Supply Availability Study Update (1994)
This 1994 report summarizes water sources available to the City, as well as evaluating existing and
future water demands for domestic use, raw water irrigation, and snowmaking. The analysis
evaluates the adequacy of supply systems, treatment capacity, water rights, and water storage
facilities to meet a variety of different water uses. In particular, the study evaluates the ability of local
streams serving as a supply source to preserve environmental values for fisheries and aesthetics
through the in-stream flow program administered by the Colorado Water Conservation Board.

The potable water supply intake points on Castle and Maroon Creeks, the hydroelectric plant on
Maroon Creek, and the existing developed municipal well at the base of Aspen Mountain (Little Nell
Well) are evaluated in the study. Other potential sources of potable water supply including Hunter
Creek, the Roaring Fork River, expansion of the City's wellfield pumping capacity, and construction
of reservoirs on Castle and Maroon Creek are considered in the study to the extent that existing
sources of supply are not adequate to meet the full range of water demands.

Water demands were projected over a 20-year period (2015) considering requests for extraterritorial
. water service and the continued growth within, th~City and-its present servic-e, territory. . While
growth of new residential units is limited under the Growth Management Quota System, current
trends with reconstruction of existing residences are expected to continue. Based on present trends,
water demand measured in ECU's connected to the municipal system is expected to increase from
the 1994 value of 12,420 ECU's to somewhere between 17,650 and18,300 ECU's by the end of the
l5-year planning period. Up to 88% of this increase is expected to occur as a result of existing water
service commitments either within the City or within existing service contract areas. A significant
factor in this increaSed demand is the current trend to remodel and reconstruct existing structures.
Recent years have seen approximately 50% of the increased demand resulting from this trend, as
opposed to building on vacant lots.

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