By David Tucker EBS Contributor
As you drive around Big Sky these days, it’s impossible not to notice an influx of pavement and other hard surfaces. Everywhere you look, parking lots, driveways, roofs, sidewalks and roads pervade, and these surfaces add up to one thing: the need for coordinated stormwater management.
What, you ask, is stormwater? And how can it be managed? The word itself—stormwater—conjures up images of hurricane-driven sideways rain and tsunami-level tidal events. Those scenarios don’t seem manageable or even likely in these parts, so what exactly are we talking about?
In the upper Gallatin watershed, we’re talking about spring snowmelt and runoff from powerful summer storms. Around this time of year, when temperatures hit the mid-40s and the snowpack starts rapidly melting, floods of running water can be seen all over town, rushing along trails and roads on their way to who knows where.
“Where” is actually the Gallatin River, and by the time this water resource has reached the Gallatin or other nearby creeks and streams, it has picked up any number of harmful pollutants along the way. Those pollutants are flushed into the Gallatin, harming aquatic life and tainting water quality.
If the smooth, hard surfaces didn’t exist, the water would naturally drain into the ground recharging our aquifers and slowly making its way to the river over the course of months or even years. With these hard surfaces, however, water rushes quickly away, leaving our groundwater reserves depleted and our surface waters like the Gallatin peaking earlier and running lower later in the year.
While this all sounds catastrophic, there is hope: stormwater management! Developing towns and cities across the world have found ways to mimic natural snowmelt and stormwater runoff patterns, tactics that lead to better groundwater recharge and cleaner surface-water discharge.
In Big Sky and throughout the upper Gallatin watershed, stormwater management regulations do exist, but they focus primarily on the construction phase of new development. The Gallatin River Task Force is working on a framework that would consider pre- and post-construction phases more comprehensively, taking a holistic approach as the area continues to see rapid growth.
“Through GIS mapping and analysis, we’re identifying opportunities and locations to capture runoff and facilitate groundwater recharge throughout the West Fork watershed,” said Emily O’Connor, conservation project manager for the Task Force. “These are the areas we can prioritize for better stormwater infrastructure.”
At a recent Big Sky Planning and Zoning Committee meeting, board members including committee chair Steve Johnson highlighted stormwater management as a priority.
“With the rapid proliferation of hard-surface parking areas in Big Sky, mitigation of stormwater runoff is becoming a concern,” Johnson said. “We are considering alternatives with the Gallatin County Planning Department, including permeable parking surfaces and vertical parking structures.”
Through education and the development of a communitywide management framework, rapid improvement is possible in a relatively short amount of time. If we continue with business as usual, we’ll see more and faster stormwater runoff, and along with it, more and worse surface-water pollution.
David Tucker is the communications manager for the Gallatin River Task Force.