Cook County Department of Transportation and Highways

Various Traffic Engineering Services

Providing On-Call Engineering Services

Since 2018, Civiltech has consulted on more than 70 different traffic and safety-related studies. This contract requires our team to work quickly and responsively in order to meet client deadlines, often turning around assignments in less than two weeks’ time. At any given time, several tasks are likely to be simultaneously ongoing, requiring constant communication with County staff to ensure our workload is prioritized according to their needs.

A Wide Array of Tasks

These studies encompass a wide array of tasks including intersection control studies, speed studies/speed limit recommendations, signage plans, pedestrian studies, crash analyses, corridor studies, review of maintenance of traffic plans, traffic counts, and reviews of Traffic Impact Studies.

Initiatives and Design Work to Assist the County

While smaller-scale traffic projects were a primary component of this contract, Civiltech also assisted the County with more substantial initiatives. These have included reviewing and updating the County’s signage and pavement marking contract, developing a checklist for County staff to use when reviewing permit reviews and traffic impact studies, and preparing grants to secure funding. Civiltech also assists with design work including conceptual geometric plans, developing intersection design studies, and analyzing improvement alternatives.

Safety Studies

Throughout the course of this contract, Civiltech has partnered with the County to improve safety. Safety Studies performed under this contract include the following showcase projects:

171st Street & 84th Avenue Intersection Safety Study – Village of Tinley Park

This study addressed concerns expressed to the County regarding excessive congestion along with frequency and severity of crashes at this signalized intersection. After an extensive analysis of crash and traffic volume data, four alternatives were identified that would improve the intersection through various combinations of modifications to traffic signal phasing, and widening the roadway or dropping a through lane to create space install left turn lanes. A detailed matrix comparing the advantages and disadvantages of each alternative was developed to aid Village and County staff in selecting an alternative.

Central Avenue Safety Study, 95th Street to 111th Street – Villages of Oak Lawn and Chicago Ridge

After a fatal pedestrian crash occurred near Richards High School in Oak Lawn, Cook County requested that Civiltech Engineering conduct a study to assess crash patterns or trends and recommend appropriate corrective safety measures for this two-mile long corridor. This study included collection of volume and speed data, field observations during school arrival and dismissal, crash data analysis, a speed study, and a gap study. The plan recommended changes to the speed limit, new crosswalks with pedestrian refuge islands, pedestrian countdown timers at signalized intersections, and modifications to the school crossing signage.

Buffalo Grove High School Pedestrian Safety Study – Village of Buffalo Grove

In response to concerns expressed by the village and high school officials, Cook County asked Civiltech to evaluate safety at an existing mid-block crosswalk on Arlington Heights Road adjacent to Buffalo Grove High School. Although collection of traffic data was not feasible because all student instruction at the school was remote, Civiltech was able to gain insights into the issues by reviewing existing available data and discussing pick-up and drop-off procedures with school staff. Civiltech recommended relocating the existing mid-block crosswalk to align better with pedestrian desire lines and to facilitate the installation of a refuge island to allow pedestrians to cross the street in two stages.

94th Street & Central Avenue Intersection Control and Safety Study – Village of Oak Lawn

The Village of Oak Lawn and Cook County asked Civiltech to recommend measures to improve safety of Oak Lawn High School students crossing Central Avenue at 94th Street. As part of this study, crash data, traffic counts, and speed data were collected and a capacity analysis was conducted to evaluate intersection performance. Short term recommendations included updating the signage to current MUTCD criteria and trimming trees to improve visibility. While changes to intersection control were not warranted, a long term plan was proposed to install a pedestrian refuge median in conjunction with Rectangular Rapid Flashing Beacons (RRFBs) to enhance safety of pedestrians crossing Central Avenue.