At first, the City of Boulder decided to stay out of the NCWCD, but rapid growth and another drought made the City think twice. In 1953, Boulder voters approved a $1 million bond to pay back taxes to NCWCD, and finance construction of Boulder Reservoir, which was finished in 1955.

The Boulder Feeder Canal, Boulder Reservoir and the Boulder Supply Canal are all part of the C-BT system, and were the last part of the system to be built.

Boulder Reservoir holds 13,270 acre-feet of water.

How big is 1 acre foot of water?

An acre-foot of water will cover a football field in a foot of water. It will supply a family of four with water for a year.
1 acre-foot = 325,851 gallons

How does Boulder use its C-BT water?

• Drinking water: C-BT water in Boulder Reservoir currently supplies the City with 20% of its drinking water.
• Irrigation water: C-BT water is owned or leased by farmers and ditch companies.
• Exchange water: the City of Boulder uses CB-T water in exchanges with downstream ditches.

C-BT water use: 50 years of change

In 1957, 85% of C-BT water was owned by agriculture, and 15% was owned by cities.

In 2007, 64% C-BT water is owned by the expanding cities and towns in Northern's boundaries.

(See chart to the right.Data courtesy of Northern Water.)