Action Alert: HWY-85
Help Protect Spearfish Creek & Canyon Climbing from Proposed US-85 Reconstruction
We Need Your Voice on the HWY-85 Proposal
Proposal Overview
A major proposal is currently on the table that could permanently alter one of the most scenic, ecologically sensitive, and recreationally significant areas in the Northern Black Hills.
The South Dakota Department of Transportation (SDDOT) has proposed a $57.6 million reconstruction of U.S. Highway 85, stretching 16 miles from the Wyoming state line to Cheyenne Crossing (US-14A). While the stated goal of the project is to address safety and roadway departures, the current design proposals rely on heavy excavation, lane and shoulder widening (up to 12-foot lanes and expanded shoulders), and expanded "clear zones."
If executed as currently drafted, this high-impact engineering approach poses severe risks to the Spearfish Creek watershed, iconic climbing areas like Icebox Canyon, and the natural character/structure of the upper canyon ecosystem.
Following widespread community feedback, SDDOT extended the written public comment period to Friday, September 4, 2026. We need the outdoor and local community to submit comments before this deadline.
Key Concerns
Landscape & Geological Integrity:
Cut-Bank Excavation & Rock Blasting: Straightening curves and expanding shoulders/clear zones requires blasting and excavating into the limestone rock walls lining the canyon.
Destruction of Natural Formations: Beyond losing rock faces, heavy blasting removes native vegetation and soil cover that naturally stabilize the slopes.
Slope Instability & Rockfall Hazards: Uncovered, fractured rock surfaces left behind are highly vulnerable to freeze-thaw cycles, accelerating erosion and increasing long-term rockfall hazards for motorists, climbers, hikers, and anglers.
Recreational Access & User Safety:
Loss of Roadside Parking: Widening shoulders and installing rigid guardrails or clear zones risks eliminating the informal roadside pull-offs that climbers use to access areas like Icebox, Shadowlands, Dark Side, The Danks and more.
Threats to Established Routes: Scaling, blasting, or stabilizing operations directly to or adjacent climbing walls can fracture natural rock features, compromise anchor placements, or alter climbs.
Safety Concerns for Recreators: Increased rockfall potential and higher traffic speeds directly threaten the physical safety of outdoor users in the canyon.
Traffic Speed & Behavioral Safety
Induced Speeding: Transportation research shows that wider lanes, paved shoulders, and expanded clear zones encourage drivers to travel at higher speeds.
Curve Hazards: On winding canyon routes, higher speeds increase the likelihood of drivers losing control on turns, leading to run-off-road crashes, cross-centerline collisions, or motorcycle slide-offs counteracting the intended safety gains of the redesign.
(https://ssti.us/2016/10/31/more-evidence-that-wider-roads-encourage-speeding/)
(https://narrowlanes.americanhealth.jhu.edu/report/JHU-2023-Narrowing-Travel-Lanes-Report.pdf)
(https://www.fhwa.dot.gov/publications/research/safety/15030/006.cfm)
Environmental & Watershed Protection
Sedimentation of Spearfish Creek: Road construction, timber removal, and added asphalt increase impervious surface area and cause heavy sediment runoff during rainstorms, threatening cold-water aquatic life and trout populations in Spearfish Creek. Local research from SDSU, the USGS, and SD Mines shows that the limestone geology of Spearfish Canyon is uniquely sensitive to excavation. SDDOT's own hydraulic guidelines acknowledge the erosion risks of cut-bank work near streams, and state water quality data from DANR confirms that cold water trout habitats like Spearfish Creek cannot handle added sediment loading.
Disturbance to Karst Topography: These studies confirm that Spearfish Creek sits directly atop porous karst geology with high surface-water and groundwater connectivity. Heavy earth-moving, rock excavation, and blasting along the canyon floor pose a direct risk of disrupting subterranean spring channels and introducing surface runoff into underground water systems.
Loss of Scenic Canyon Character: Clear-cutting mature timber and blasting away natural rock walls permanently strips upper Spearfish Canyon of its wild, rustic aesthetic and disrupts local wildlife corridors.
(https://www.ugpti.org/resources/reports/downloads/mpc20-418-brief.pdf)
(https://pubs.usgs.gov/wri/wri024094/pdf/wri024094.pdf)
(https://dot.sd.gov/media/94716790/Chapter%2004-Planning%20and%20Location%20%28Hydraulics%29.pdf)
BHCC Vision & Position
The Black Hills Climbers Coalition advocates for the protection of Spearfish Canyon’s natural geology, watershed integrity, and public recreational access. While we recognize the importance of ongoing highway maintenance, we urge SDDOT to adopt a low-impact, context-sensitive design that addresses safety without sacrificing the environment of Spearfish Canyon.
1. Maintenance-First Focus Over Corridor Expansion
We fully support pavement repair, routine wear-and-tear upkeep, and targeted surface maintenance to keep US-85 safe and functional. However, we oppose widening shoulders, straightening curves, and clearing roadside slopes. Focusing resources on localized maintenance accomplishes necessary safety goals without inducing higher traffic speeds, blasting rock faces, or destroying the canyon’s rustic character.
2. Preserve Essential Recreation Access & Parking
Roadside pull-offs near Icebox, Shadowlands, Sunshine, and surrounding crags are vital access points for climbers, anglers, and outdoor enthusiasts. SDDOT must preserve existing roadside parking or construct dedicated, designated replacement pull-offs so public access is not permanently eliminated by guardrails or widened clear zones.
3. Protect Geological Integrity & Prevent Rockfall Hazards
Limiting large scale cut bank excavation and rock blasting along narrow canyon walls is critical. Disturbing natural rock features strips away stabilizing vegetation and soil, exposing fractured surfaces to freeze thaw cycles that heighten long term slope instability and create chronic rockfall hazards for visitors and motorists.
Collaborative Mitigation (If the Reconstruction Project Proceeds)
If SDDOT chooses to move forward with the broader reconstruction design, the BHCC strongly encourages the state to collaborate directly with local recreational and environmental groups. To minimize lasting harm, SDDOT must:
Enforce Advanced SWPPP Controls: Implement a site specific Stormwater Pollution Prevention Plan (SWPPP) utilizing soil tailored sediment capture methods to prevent fine soil particles from silting over cold water trout habitats in Spearfish Creek.
Establish Stakeholder Working Channels: Engage with local watershed experts, conservation organizations, and the BHCC throughout the final design and construction phases to mitigate access disruptions.
Conduct Post Construction Safety Audits: Perform comprehensive slope stability assessments near active climbing/fishing areas to verify long term safety following ground disturbance.
Make Your Voice Heard
Ryan Schaefer Photo | Mountain Project Source
The future of upper Spearfish Canyon depends on public participation. SDDOT needs to hear directly from climbers, anglers, local residents, and outdoor enthusiasts who value this canyon's natural character and recreational access.
Follow these simple steps to submit your formal written comment before the September 4, 2026 deadline:
1. Submit Your Written Comment
Send an email directly to the project managers, or submit your feedback online through the state portal.
Email SDDOT: Send your letter to Mark Malone (SDDOT Project Manager) at mark.malone@state.sd.us and CC Steve Murray at steve.murray@fhueng.com.
2. Copy & Paste Email Template
Feel free to use or adapt this template below for your email if you are having trouble curating your response:
Subject: Public Comment – US-85 Reconstruction Project (Lawrence County)
To: Mark Malone (
mark.malone@state.sd.us)Cc: Steve Murray (
steve.murray@fhueng.com)Dear Mr. Malone,
As a user of upper Spearfish Canyon, I oppose the proposed US-85 expansion. Blasting and excavation cause severe sediment runoff into Spearfish Creek's trout waters, risk disrupting limestone spring channels, and destabilize rock faces creating ongoing rockfall hazards while destroying critical roadside parking/access for recreation.
I urge SDDOT to reject a full reconstruction and limit work strictly to minor pavement repairs and routine maintenance. I align with the Black Hills Climbers Coalition and ask that you reject this expansion.
Sincerely,
[Your Name]
[City, State]
3. Spread the Word
Share This Post: Send this link to fellow climbers, outdoor partners, and local community members.
Attend BHCC Meetings: Stay connected with the Black Hills Climbers Coalition for ongoing updates as the public comment period closes.
Deadline for Written Comments: Friday, September 4, 2026
Ethan C Photo | Mountain Project Source