Environmental Finance Center, EPA Region 6, New Mexico Tech

Boulder, Lefthand, and Longmont, Colorado

Location

The City of Boulder is located in northcentral Colorado about an hour northwest of the City of Denver. Lefthand and Longmont water systems are located in close proximity to Boulder.

Water Supply

Currently, the City of Boulder has three sources of water supply: the Barker Reservoir, the Lakewood Reservoir, and the Boulder Feeder Canal and associated Boulder Reservoir. The Barker and Lakewood Reservoirs currently provide about 80% of the supply to Boulder, with the Boulder Feeder Canal (BFC) and Reservoir providing the remaining 20%. However, the BFC is becoming increasingly important as growth occurs. The BFC also provides some of the water supply to Lefthand and Longmont. This project was only concerned with the BFC as a water supply. The BFC water is supplied by Northern Colorado Water Conservancy District.

Source Water Assessment

The Colorado Department of Public Health and the Environment performed a source water assessment for the water systems. Unfortunately, the state was unable to treat the open canal as the source of supply and instead simulated this supply as a closed pipe. This assessment methodology made it necessary for the source water protection team of Boulder, Longmont, and Lefthand to complete its own assessment of risks created by the open canal.

Local Team

The source water protection efforts are being led by representatives from Boulder, Longmont, Lefthand, and the Northern Colorado Water Conservancy District (Northern).
The local entities that receive BFC water are working with Northern to establish a Southern Carter Lake users group. Carter Lake supplies water to the BFC and several other water treatment facilities. The users group would address many issues related to water supply in addition to source water protection. This users group will allow the water systems to continue and expand partnering efforts.

Priority Contamination Threats

The nature of the open canal makes it very vulnerable to contamination. There are numerous direct outfalls that collect runoff from residential or agricultural areas that can convey contamination directly into the canal. In addition, there are concerns related to the establishment of a recreational trail along the canal that would have the potential for animal waste to enter the canal or for vandalism to occur. The Boulder Reservoir is also used for recreation, which is another potential source of contamination.

Protection Measures

As a long term protection measure, the group would like to consider the possibility of a pipeline to convey the water from Carter Lake to Boulder Reservoir. The group is still considering short term measures. Public educational efforts have begun in Boulder with some open houses related to source water protection.

Environmental Finance Advisory Board

EPA Environmental Finance Program

EPA Region 6 Drinking Water Program