Study Location
The study is located at the intersection of Spring Grove Road at Miller Road in McHenry County.
Project Schedule
The project schedule is shown below as it progresses from initiation in Phase I to construction in Phase III. The schedule below is subject to project readiness and funding availability.
- Phase 1 includes all tasks related to preliminary engineering and environmental studies, in pro-gress now, which will take place during the years 2024-2026. The phase 1 schedule has four stag-es. Stage 1 took place in 2024 and included gathering and analyzing existing data, used for devel-opment of the Purpose and Need, traffic and safety analysis, drainage studies, environmental surveys, and stakeholder meetings. Stage 2 takes place in 2025 and includes developing and ana-lyzing initial alternatives, used to identify concepts to address project needs, and identify oppor-tunities to minimize impacts. Public Information Meeting #1 takes place during this phase, in the Spring. Stage 3 will take place in 2025 and 2026 and includes identifying the preferred alternative. In this stage, the team uses public feedback to evaluate the initial alternatives, develops the pre-ferred alternative, and hosts Public Information Meeting #2 in Fall of 2025. In early 2026, Phase 1 of the study is completed and the design is approved.
- Phase 2 begins next, which will include land acquisition and contract plan preparation. It will take place from 2026 to 2028, pending project readiness and funding availability.
- Phase 3 includes project construction, and is expected to take place in 2028.
Purpose and Need
The Purpose for the project is to improve safety for all users of the intersection.
The Need for the project includes addressing the geometric deficiencies of the Spring Grove Road at Miller Road intersection due to the history of crashes, which includes angle crashes, that were a result of:
- Disregarding traffic control devices
- Failure to yield the right-of-way
- Seasonal limited sight distance
- Seasonal high traffic volumes
- Lack of familiarity with intersection from non-local motorists
Existing Conditions
Spring Grove Road at Miller Road is a rural intersection controlled by stop signs in each direction on O'Brien Road only. Both roads have a single travel lane in each direction with minimal paved shoulders.
| Road | Spring Grove Road | Miller Road |
|---|---|---|
| Speed Limit | 55 mph | 45 mph |
| Jurisdiction | McHenry County | McHenry Township |
Average Daily Traffic (ADT) Flow
Traffic counts were performed during 24 hours on a weekday and fall weekend in 2023 to collect existing traffic volumes. The Chicago Metropolitan Agency for Planning (CMAP) provides 2050 traffic volumes based on anticipated land use changes in the region. The existing weekday volume and predicted growth indicate that the current number of lanes accommodate the existing and projected future weekday traffic demand.
- Spring Grove Road southbound: 6250 traffic volume currently; 8300 future traffic volume
- Spring Grove Road northbound: 6100 traffic volume currently; 8100 future traffic volume
- Miller Road eastbound: 600 traffic volume currently; 800 future traffic volume
- Miller Road westbound: 650 traffic volume currently; 850 future traffic volume
Legend
- X,XXX Existing 2023 ADT
- (X,XXX) Future 2050 ADT
High traffic volumes on fall weekends create consistently poor traffic conditions along Miller Road while attempting to turn onto, or cross, Spring Grove Road. These conditions are expected to worsen in the future.
Safety
Deficiencies documented at the intersection contribute to an increased risk of crashes, injuries, and fatalities.
Crash History (2019-2023)
- 16 Crashes
- 26 Injuries
- 17 Angle
- 8 Turning
- 1 Front to Rear (Rear End)
- 2 Serious Injuries
- 2 Turning
- 1 Fatality
- 1 Angle
By Crash Type
By Crash Severity
- Type A: Incapacitating Injury
- Type B: Non-Incapacitating Injury
- Type C: Non-Evident Injury
- PDO: Property Damage Only
Crash Categories
By Potential Crash Cause*
- Failing to Yield Right-of-Way 53%
- Disregarding Stop Sign 31%
- Improper Lane Use 12%
- Failing to Reduce Speed to Avoid Crash 12%
- Driving Skills / Knowledge / Experience 7%
Crash History (2019-2023): Fall Weekends Only
- 7 Crashes
- 14 Injuries
- 8 Angle
- 6 Turning
- 2 Serious Injuries
- 2 Turning
- 0 Fatality
By Crash Type
By Crash Severity
- Type A: Incapacitating Injury
- Type B: Non-Incapacitating Injury
- Type C: Non-Evident Injury
- PDO: Property Damage Only
Crash Categories
By Potential Crash Cause*
- Failing to Yield Right-of-Way 72%
- Disregarding Stop Sign 29%
- Driving Skills / Knowledge / Experience 13%
Deficiencies or problems contributing to crashes
Disregarding traffic control devices or failing to yield right-of-way to oncoming traffic
- Misconception that intersection is an all-way stop
- Limited sight distance during growing season
- Insufficient gaps for turning vehicles, especially during busy fall weekends
Lack of familiarity with intersection from non-local motorists
Lack of paved shoulders on Miller Road
Alternatives
This section presents several transportation alternatives identified to address the project Purpose and Need.
-
Alternative 1: Existing Intersection (No Build)
Existing Conditions:
- One lane in each direction
- Substandard paved shoulder widths
- Maintain existing two-way stop
-
Alternative 2: Roundabout
Improvements include:
-
Improved safety
- 90% reduction in fatal crashes
- 83% reduction in angle crashes
- 75% reduction in injury crashes Federal Highway Administration, FHWA
- Reduced conflict points
- Slower speeds through the intersection
- Shoulder and ditch widening
- Pedestrian and bicycle accommodations
-
Improved safety
-
![Alternative 3: Restricted Crossing U-Turn [RCUT]](images/SpringGrove-Miller-Alt3_RollPlot_Opaque-small.jpg)
Alternative 3: Restricted Crossing U-Turn [RCUT]
Improvements include:
- Reduced likelihood for angle and left turning crashes
- Maintaining free flow traffic on Spring Grove Road
- Depressed median and U-Turn bump outs on both sides of Spring Grove Road
- Shoulder and ditch widening
- Pedestrian and bicycle accommodations
Federal Highway Administration, FHWA
-
Alternative 4: Shoulder Widening with Left Turn Lanes
Improvements include:
- Widened shoulders
- Added left turn lanes on Spring Grove Road
- Maintaining free flow traffic on Spring Grove Road
- Pedestrian and bicycle accommodations
![Alternative 3: Restricted Crossing U-Turn [RCUT]](images/SpringGrove-Miller-Alt3_RollPlot_Opaque.jpg)
Alternatives Evaluation
The table below compares alternatives based on both their ability to address intersection deficiencies effectively and the potential for impacts to environmental features or adjacent properties
| Evaluation Category | Alternative 1 Existing Intersection (No Build) | Alternative 2 Roundabout | Alternative 3 Restricted Crossing U-Turn [RCUT] | Alternative 4 Shoulder Widening with Left Turn Lanes |
|---|---|---|---|---|
| Crash Reduction | Negative Improvement |
Satisfactory Improvement |
Satisfactory Improvement |
Satisfactory Improvement |
| Speed Reduction | No change |
Satisfactory Improvement |
Negative Improvement |
Minimal Improvement |
| Intersection Visibility | No change |
Satisfactory Improvement |
Satisfactory Improvement |
Minimal Improvement |
| Turn Movement Improvements | Negative Improvement |
Satisfactory Improvement |
Minimal Improvement |
Satisfactory Improvement |
| Improved Shoulders | No change |
Satisfactory Improvement |
Satisfactory Improvement |
Satisfactory Improvement |
| Environmental Impacts | No change |
Minimal Improvement |
Negative Improvement |
Minimal Improvement |
| Number of Properties Impacted | No change |
4 Properties (minimal) |
23 Properties (negative) |
4 Properties (minimal) |
| Cost | No change |
Minimally Impacted Cost |
Negatively Impacted Cost |
Minimally Impacted Cost |
-
No change
-
Negative impact
-
Minimal improvement/impact
-
Satisfactory improvement/impact
Contact Us
Please visit the project website for more information.
You can contact the project team by email or mail with questions or comments.
Project Website
McHenry County Division of Transportation
Attn: Rebecca Brazas, Project Manager
16111 Nelson Road
Woodstock, IL 60098
Comments due May 22, 2025.
