Lefthand Brewing Company has put in their development application for a “cultural event center” adjacent to St. Vrain Creek. (Supporting documents for the application can be found here.) This facility is planned to consist of a beer garden and temporary stage that will be designed to accommodate up to, but not limited to, 1,500 people per event. Though this development is not planned to encroach upon the 150 foot riparian conservation buffer, Stand With Our St. Vrain Creek is concerned about the noise pollution resulting from this facility.
The acoustic study done for the proposal anticipates that concerts at the venue will likely be 95 DBA at the back of the audience, or occasionally 100 DBA for larger events. This is based on volume readings done at Lefthand Brewing concerts currently held at Roosevelt Park. While sound tapers off the farther away from the source, it is anticipated that the noise from the facility could be as high as 77 DBA for residences across St. Vrain Creek to the south. Per Lefthand Brewing’s own acoustic study, 77 DBA is louder than a large dog barking 50 feet away. Lefthand has not provided any proposed mitigation of this noise pollution.
Water carries sound and, with most of the vegetation being removed from the river channel as part of the Resilient St. Vrain flood mitigation project, the noise pollution from the unspecified number of events at Lefthand’s proposed event center each week will carry up and downstream. While residents nearby are likely to be annoyed, such noise pollution could be much more damaging to wildlife using the river corridor. Wildlife tends to move at night, when it’s most likely that concerts will be happening. That means that the area around this new facility could become a bottleneck along a proven wildlife movement corridor. For resident animals, such as birds, studies have shown that noise pollution increases stress levels and shortens lives.
As mentioned, Lefthand has not provided any proposed mitigation of their noise pollution. We expect they will try to get new code requirements instituted that will allow a higher threshold for noise pollution. The Longmont municipal code currently restricts noise in residential areas to 55 DBA during the day and 50 DBA at night. Because the decibel scale is logarithmic rather than linear, this means that 77 DBA is over 4 times as loud as 50 DBA.
Please send your comments to Brien Schumacher at Brien.Schumacher@longmontcolorado.gov, the Longmont City Planner assigned to this project and tell him that Lefthand Brewing must mitigate the noise from their events rather than changing the rules to suit them.