Nonconforming Use Permitted to Continue at CEMEX Cement Plant in Lyons

Boulder County, Colo. - Today (May 19, 2026) Boulder County Community Planning and Permitting Director Dale Case sent a Rescission of Notice of Termination of Nonconforming Status letter to CEMEX, Inc., reinstating the company’s right to operate its cement plant near Lyons.

After a comprehensive review of all information provided to Director Case since the prior determination, including new information from Boulder County residents, Director Case has determined that CEMEX provided satisfactory evidence that the termination determination was made in error. Specifically, the evidence shows that there was no significant increase in truck traffic to and from the Property since the closure of the Dowe Flats Quarry, compared with 1994 traffic numbers.

Therefore, Director Case rescinds the determination that increases in truck traffic at the CEMEX cement plant, since the closing of the Dowe Flats Quarry, constitute an enlargement or alteration of the nonconforming use which has the effect of creating a hazard or nuisance off the property, adversely affecting the character of the neighborhood, or intensifying the use of the land and its need for services under Article 4-1003.C.I.d of the Boulder County Land Use Code.

CEMEX may continue its operation of the nonconforming cement plant use on the Property, provided it is in compliance with all applicable requirements of the Land Use Code.

View the documents reviewed by Director Case on the CEMEX Lyons Cement Plant and Dowe Flats Quarry webpage.

Background

The CEMEX plant in Lyons has been in operation since 1965, but, in 1994, Boulder County amended its Land Use Code (the Code) to require Special Use approval for these types of operations. As a result, the cement plant became a nonconforming use. Under the Code, uses that do not conform with the Code are allowed to continue, but they generally cannot be expanded or altered.

On April 10, 2024, Director Case issued a determination that the right to continue the nonconforming CEMEX cement plant use at 5134 Ute Highway was terminated by operation of Article 4-1003.C of the Code on the basis of increased traffic.

The 2024 determination was based on the best information available to Director Case at the time. In particular, the determination relied on traffic data from the August 28, 2023, CEMEX Lyons Access Traffic Study. The study appeared to show a significant increase in traffic to and from the Property and appeared to support the determination that the truck traffic at the CEMEX cement plant had increased to a level that constituted an enlargement or alteration of the nonconforming use under Article 4-1003.C.I.d of the Code. Under Article 4-1003.H.1, CEMEX had the option of providing evidence satisfactory to the Community Planning and Permitting Director that the determination was made in error.

Prior News Releases

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