What’s the Issue?

Longmont’s 100-year flood mitigation project “Resilient St. Vrain” will impact the entire length of St. Vrain Creek from Airport Road to the confluence of St. Vrain and Boulder Creeks.  The most dramatic changes to the St. Vrain will occur in the “city reach” especially between Lefthand Creek and the BNSF railroad bridge, where the creek channel will be widened and deepened.  This means removing a majority of mature trees lining the creek, including many cottonwoods.

After flood mitigation work is complete, landowners, developers, and the City of Longmont intend to do massive redevelopment along St. Vrain Creek between Main Street and Boston Avenue, which will include residential housing, restaurants, outdoor decks, and businesses.  This is not only unwise considering there have been 11 recorded flood events along the St. Vrain corridor since 1876, but we are likely to see another major flood event in our lifetimes.  It will also be detrimental to the health of the creek, the surrounding riparian habitat, resident wildlife, and people’s enjoyment of a natural area.  Longmont has lots of well-manicured city parks but only one “wild jewel of nature” running through the middle of our city.  Let’s preserve and protect it!

What are the Environmental Impacts?

  • The widening and deepening of the creek channel may destroy aquatic habitat unique to St. Vrain Creek, which has been described by Colorado Parks and Wildlife (CPW) as having immense conservation value to the State of Colorado.  Biologists do not know why rare, native fish, such as the Common Shiner and Brassy Minnow, both state-listed threatened species, have persisted in the city reach.  CPW states it is “likely a result of unique water quality and microhabitat preferences that have been prevalent in the reach and lost in other places.”
  • Other rare, native fish species in the creek include the Stonecat,* Iowa Darter,* Johnny Darter, and the Plains Topminnow.  All species mentioned above are Boulder County species of special concern.  The asterisk (*) indicates a Colorado Species of Special Concern.
  • Removal of mature tree canopy from creek banks may degrade the integrity of the creek as a wildlife corridor and a hotspot for raptors.  Terrestrial wildlife use the creek as a habitat connector to get from one natural area to another.  For example, bobcats with kittens traveled along the St. Vrain corridor last spring to relocate from the foothills to Sandstone Ranch.  Large, mature trees are also used by raptors for nesting and perching.  Extensive removal of large trees and vegetation from creek banks will severely impact the wildlife corridor for a generation or more.
  • Any reductions in the recommended 150-foot setback from the creek for new development will negatively impact the wildlife corridor.  Many animals are active at night and cautiously move through the corridor to avoid people.  Light and noise pollution generated by nearby development, such as bars and restaurants, will damage this migration.
  • Extensive removal of mature shade trees lining the creek may cause elevated stream temperatures.  This is a serious concern considering the rare, native fish that inhabit the St. Vrain are glacial relics and prefer the cool waters of a transitional stream.
  • One city proposal to construct an additional floodway south of St. Vrain Creek at Roger’s grove will require over 50% of Fairground Lake to be filled in.  This would result in the loss of foraging and nesting habitat for waterfowl, wading birds, and shorebirds.  Important breeding habitat along the creek for Bank Swallows, a Boulder County Species of Special Concern, could also be negatively impacted or destroyed.
  • Animals that may be negatively impacted by the Resilient St. Vrain project and potential extensive redevelopment along the creek corridor include, but are not limited to:  Great Blue Heron, Osprey, Great Horned Owl, Bank Swallow, Spotted Sandpiper, red fox, muskrat, coyote, black bear, and deer.

What Can We Do?

  • Contact the seven community board members of the Longmont Planning and Zoning Commission and urge them to retain the 150-foot creek setback, as currently written in the municipal code, and reject requests for variances to decrease the setback for new construction or redevelopment along our entire St. Vrain Creek corridor.

Send your comments to the commission’s staff liaison Joni Marsh at joni.marsh@longmontcolorado.gov.

  • Contact all Longmont City Council members and urge them to:

⇒Ensure that comprehensive baseline wildlife surveys are completed before construction begins;

⇒Preserve the large, mature trees, especially cottonwoods, along the creek banks, and re-create the small tree/shrub understory;

⇒Keep new development and redevelopment away from St. Vrain Creek;

⇒Reevaluate and revise our Longmont Comprehensive Plan as it applies to properties in proximity to the area impacted by the 2013 flood using current flood plain information.  Request that the revised Comprehensive Plan take wildlife impacts into account and adopt the least destructive option that will preserve wildlife habitat while mitigating the impact of future floods on the community.

You will find city council contact information here.

Considering the HUGE public investment ($133 million and counting) for the Resilient St. Vrain project, the public should have a significant voice in what type of development might be built.  At the very least, this means keeping the 150-foot setback, as currently written, with NO VARIANCES granted to reduce the setback.