Thornton 2002 WCPlan

• Project Type: Water Conservation Plan
• Project Name: City of Thornton Water Conservation Plan
• Title: Water Conservation Plan
• Date: 2/6/2002
• County: Adams
• Water Conservation - Doc Type: Complete Plan

BACKGROUND

The City of Thornton has one of the lowest daily per capita water consumption rates
among cities in the Front Range. Several factors influence this low use: lot sizes, housing
characteristics, water rates, water conservation practices, and income levels. The City' s
water rate increases in the late 1980s, which were set to cover costs of operation, debt
service, and long-term infrastructure development, also had substantial impact on
customer behavior. Consequently, per capita water use went down.

Thornton's Water Supply

The Chy of Thornton obtains hs water from the South Platte River basin and the Clear
Creek basin.

Water from the South Platte basin is obtained through Thornton's ownership in ditch and
reservoir companies that own water rights associated with the Burlington Canal as well as
other water rights from the basin. Water diverted from the Burlington is stored in
reservoirs along the South Platte River and treated at the City's Columbine Water
Treatment Plant.

The Clear Creek basin water supply is also obtained through Thornton's ownership in
ditch and reservoir companies. For operational purposes, the Clear Creek basin is
divided into upper and lower systems. Water from the lower system is stored in
reservoirs along the western side of the South Platte River. Water from the upper system
is stored in Standley Lake and conveyed to the Thornton Water Treatment Plant through
an eleven-mile pipeline.

Availability and Storage

Thornton's water supply becomes most plentiful during snowmeh runoff in spring and
early summer. Due to seasonal variations in availability of water, Thornton has
developed reservoir storage fucilities that allow the City to provide water during low-flow
periods when inflows to the City's reservoirs are less than outflows for customer demand.
n Thornton t)'pically: fillsits-reserVOll-storag01 spacein-eafiy- to- mid- -June dill ing the peak - -- -
snowmelt runoff.

Thornton's current storage system has seventeen reservoirs with a combined total storage
capacity of31,016 acre-feet. New reservoirs are in the process of being developed to
meet the future needs of the City and its service area.

Water Service Area and Demand

The City of Thornton 2000 Water and Wastewater Systems Master Plan estimates the
size of the existing service area to be 20 square miles. Based on population data from the
ZOOO census, Thornton's population is 82,384. Thornton also provides water service to
portions of unincorporated Adams County with a 2000 population of 15,080. Water
demand for the service area in 2000 was 20,412 acre-feet.

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