Safety Initiative McHenry County Spring Grove Road at Miller Road Online Meeting

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 progress 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 development 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 analyzing initial alternatives, used to identify concepts to address project needs, and identify opportunities 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 preferred 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

What We’ve Heard

“There have been many serious accidents at this intersection in the last ten years.”
“Drivers do not always come to a complete stop before proceeding through the intersection.”
“Drivers sometimes don’t pay attention and fail to stop.”
“Speeding is a problem near the intersection. There is a need to slow traffic down.”
“Visitors unfamiliar with the intersection often assume it to be a four-way stop.”
“Approaching vehicles on Spring Grove Road can be difficult to see.”
“Crashes, especially in the fall, are a consistent issue at this intersection.”
“Something needs to be done to make the intersection safer.”

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.

The intersection has stop signs on Miller Road at the intersection with Spring Grove Road. Miller Road has Stop Sign Ahead signage to warn drivers in both directions. Spring Grove Road has signs to show that O'Brien road is ahead

Example of road signs

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 Weekday ADT
X,XXX Existing 2023 Weekend ADT
(X,XXX) Future 2050 (Roundabout) Weekday ADT

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.

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

Front to Front at 6%, Front to Rear at 6%, Fixed at 13%, Turning at 13% and Angle at 62%

By Crash Severity

Type A crashes at 6%, Type B at 50%, Type C at 6%, PDO at 31% and Fatal at 7%

Crash Categories

Type A: Incapacitating Injury
Type B: Non-Incapacitating Injury
Type C: Non-Evident Injury
PDO: Property Damage Only

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%

*Each crash may have up to two potential causes identified.

8 crashes occurred in 2024 - 2025

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

Angle Crashes are 86% and Turning Crashes are 14%

By Crash Severity

Type A crashes at 14%, Type B at 42%, Type C at 14%, and PDO at 28%

Crash Categories

Type A: Incapacitating Injury
Type B: Non-Incapacitating Injury
Type C: Non-Evident Injury
PDO: Property Damage Only

By Potential Crash Cause*

Failing to Yield Right-of-Way 72%
Disregarding Stop Sign 29%
Driving Skills / Knowledge / Experience 13%

*Each crash may have up to two potential causes identified.

3 crashes occurred in 2024 - 2025

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

Preferred Alternative - Roundabout

This section presents the preferred alternative identified to address the project Purpose and Need.

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
Intersection lighting