Resilient St. Vrain
Trees play an essential role in our community, helping to improve air quality and reduce the effects of pollution, as well as providing habitat for wildlife and contributing to a more aesthetically pleasing cityscape. Learn more about Longmont’s Urban Forest >
As an important piece of a healthy ecosystem, trees are one component of the overall Resilient St. Vrain project goal of completing the work in an environmentally sensitive manner. The project includes removal of a variety of trees, including native Cottonwoods damaged in the September 2013 floods and non-native or invasive tree varieties, such as Russian olive. Additional trees are slated for removal to allow for healthy tree spacing and to create the capacity necessary to safely convey 100-year flood flows throughout Longmont.
Tree spacing plays a critical role in the resilience of the creek channel. In the September 2013 floods, debris built up against densely packed trees in along the St. Vrain Creek, creating walls of debris that slowed down stormwaters.
Appropriate tree spacing allows water to flow around the trees, even as debris may pile up in front of trees. This healthy spacing can prevent blockages along the creek, while continuing to provide areas for wildlife to move along the corridor.
Protecting Wildlife Habitat
A variety of wildlife, including protected native birds and fish, live in and around the St. Vrain Creek. Monitoring and protection of this wildlife is ongoing throughout Resilient St. Vrain construction.
Wildlife biology experts, including Colorado Parks and Wildlife, help evaluate trees along the St. Vrain Creek channel for avian nests and other crucial habitat factors, and project contractors receive environmental awareness training. Additionally, safety buffers and work timelines have been implemented to ensure wildlife protection throughout the work areas.
Replanting Trees, Shrubs and Grasses
New, native vegetation will be planted along the St. Vrain Creek as construction is completed in each section. As shown in the sample progression images on this page, vegetation will not be replanted exactly as it was prior to construction. Plantings will provide refuge areas for wildlife, birds and fish along the creek, while also considering public safety and the safe conveyance of flood flows. View a list of species planted through the Resilient St. Vrain Project >
Work on the Resilient St. Vrain project complies with Longmont’s municipal code ordinances related to Forestry. Generally, this code requires replanting equivalent quantities of quality trees or contributing to a City fund that allows for planting as needed elsewhere within Longmont’s urban forest. These fund contributions will be especially helpful after the 2016 discovery of Emerald Ash Borer within Longmont.
Project Payments to City Tree Fund
- City Reach 1 $195,333
- City Reach 2A $487,600
Looking to the Future
Throughout the design process for Resilient St. Vrain, careful consideration has been given to ensuring that healthy trees are a part of the St. Vrain Creek ecosystem. The images below show illustrations of two areas along the St. Vrain Creek.
- The first image in each group ("Current") shows a current view of the area (post-flood and pre-construction)
- The middle image ("Post-Construction") illustrates how the area is anticipated to look once construction work is finished, landscaping has occurred, and the newly seeded areas are established
- The final image ("Mature Vegetation") illustrates how the area is projected to look once trees and other vegetation reach maturity (approximately 15-20 years after construction)
- Download a PDF containing all 6 illustrations shown below >
The first three images are for the area from Main Street looking west to South Pratt Parkway. Click on an image to open a larger version.
Main Street to South Pratt Parkway (looking west): Current
Main Street to South Pratt Parkway (looking west): Post-Construction
Main Street to South Pratt Parkway (looking west): Mature Vegetation
The three images below show the same progression in the area from South Pratt Parkway looking west to the BNSF railroad bridge (near Price Road). Click on an image to open a larger version.
South Pratt Parkway to BNSF railroad bridge (looking west): Current
South Pratt Parkway to BNSF railroad bridge (looking west): Post-Construction
South Pratt Parkway to BNSF railroad bridge (looking west): Mature Vegetation
Looking to the Past
The St. Vrain Creek is constantly evolving. Historical images show a vastly different creek area, with significantly fewer trees along its bank, than we see today.
As part of its collection, the Longmont Museum has several historical images of the St. Vrain Creek. View images taken by former City Council member Virginia Estes, who completed the St. Vrain Greenway Project in 1968 >The map images below are from the Public Works & Natural Resources map collection. The St. Vrain Creek is at the bottom of each image. Click on an image to open a larger version.