Engineering Design Source, Inc.

16141 Swingley Ridge Rd
Chesterfield, MO 63017
Phone: 636.537.5585

Transportation Design

EDSI’s core strength from its inception has been the expertise in transportation planning, design, and complementary traffic engineering services. We take great pride in almost 2 decades of work on many of the region’s signature transportation projects. Our staff has thorough knowledge of local, state and federal design standards and methodologies, and they are comfortable and proactive in representing our clients’ interests with appropriate governmental entities.


Our most recent example of design innovation is the continuous-flow intersection (CFI) we developed in St. Louis County for MoDOT. This intersection is the first of its kind in Missouri and only the fifth CFI to be designed in the United States.


General Transportation Services Include:

– Interchanges (Single Point Urban, Full to Partial Clover, Directional, and Diamond)

– Widening and Re-Routing

– New Locations

– Preliminary & Final Design

– Intersection Geometrics and Warping Details

– Retaining Wall Design

– Open and Enclosed Drainage Design

– Cross-Sections and Earthwork/Grading

– Right-of-Way Plans

– Traffic Control and Construction Phasing

– Temporary Erosion and Sediment Control

– Construction Cost Estimates

– Bicycle & Pedestrian Pathway Design


transportation experience


Lambert – St. Louis International Airport – Concourse C Taxiway Improvements

Location: St. Louis, Missouri

EDSI was selected to be part of a team providing the design for demolition and reconstruction of approximately 28,000 square feet of concrete pavement panels on the apron and taxiway at Lambert St. Louis International Airport. This project area, for removal and replacement of pavement, consisted of Taxiway Golf between Taxiway Papa and Runway 12R, the Northwest Air Carrier Apron, and the Concourse C Extension Apron.


EDSI was specifically responsible for the design associated with demolition and reconstruction of approximately 7,900 square feet of pavement panels just east of Concourse C. Additionally, EDSI designed the removal and replacement of 5 aviation fuel line hydrant structure pits and 1 fuel line high point vent structure pit located in the pavement.


Major tasks completed during the design of the Concourse C pavement included: development and completion of as-built construction documents for the entire project area, as well as construction administration services for the design of the Concourse C Extension Apron area to include Construction phasing (such as positioning of design aircraft to accommodate usable gates during construction), evaluation of drainage for the area to come up with a demolition plan of all existing pavement around structures and aviation fuel line components to remain in place, joint elevation and layout to accommodate expansion joints in new pavement (where new pavement was adjacent to existing pavement and where manholes or other structures were present within a pavement panel), grading and drainage, and replacement of pavement marking. Surveying tasks consisted of topographic survey and base mapping.


EDSI was specifically responsible for locating all existing topographic items within the identified areas including existing drainage structures, joint detail, utilities, pavement marking, lighting/electrical, and other pertinent features.



Grand Avenue Viaduct Reconstruction

Location: St. Louis, Missouri

Grand Ave

EDSI was selected as a sub-consultant to perform the engineering and design services on the replacement of this Viaduct, which was originally designed in 1959 and features 14 spans of structural steel for a bridge which is 1,165 feet in length with an 80-foot wide deck of six traffic lanes plus sidewalks.


The first phase of our work detail included data collection, a feasibility study to determine the extent of rehabilitation and replacement cost options, leading to the preparation of preliminary plans for review and approval. The second phase included the preparation of right-of-way plans and final designs.


Two critical issues surfaced during the project. The first was the need to reduce construction costs to fit within the budget. We maximized the use of embankment and MSE walls to reduce structure cost, and determined ways to lower profile cost and minimize fill. The second was the need for multimodal connectivity linking the north and south sides of the Mill Creek Valley with Metrolink transit. EDSI designed ADA-compliant pathways with bus turnouts on each side, giving easy access to Metrolink elevators.


“EDSI was a pleasure to work with and went out of their way to produce a top quality set of plans.” Kevin Kriete, PE



Route 30 – Continuous Flow Intersection (CFI)

Location: St. Louis County, Missouri


EDSI was engaged as a sub-consultant by MoDOT to design a new Continuous Flow Intersection (CFI) as an incorporated element of the renovation of State Route 30 in St. Louis County. This CFI is the first for Missouri and only the fifth in the nation.


The idea behind a CFI is to eliminate the conflict between left-turning vehicles and oncoming traffic at an intersection by creating a left-turn bay placed to the left of facing oncoming traffic. Traffic is permitted to cross the on-coming traffic lane and load into this left-turn bay during the signaling of cross-street traffic.


EDSI’s portion of the project included project management and design of construction plans for the intersection reconstruction, and the addition of a new City Street at the fourth leg. The project details included easements, alignments, profiles, intersection geometrics, warping details, open and enclosed drainage design, signing, pavement markings, traffic control, cross-sections, and quantities. Drainage design included extensive use of slotted drains on flat grades and a 520-foot extension of a 6′ x 8′ box culvert. Project also included new traffic signals.


This innovative approach is designed to reduce commuter travel time, energy consumption and improve overall commuter safety. Initial estimates by MoDOT indicate that this unique approach reduces traffic time delays at the intersection by 32% versus a conventional intersection. As the area continues its development and the traffic volume proportionally accelerates, this forward-looking approach is projected to reduce delays by more than 70%.


“Very professional work considering the tight schedule and coordination with two design teams.” Jim Provinse



The New I-64

Location: St. Louis City, Missouri

New I-64

EDSI was selected as a sub-consultant to assist MoDOT with management of this two-year, $535 million project. The initiative involves a comprehensive rebuilding and upgrading of all pavement, bridges and interchanges for a nine-mile stretch of urban interstate between Spoede Road in St. Louis County and Kingshighway Blvd. in St. Louis City. The overall design objective is to provide improved traffic flow and enhanced safety by updating this 60-year-old infrastructure to better reflect current and future transportation needs. EDSI served as a member of MoDOT’s Traffic Task Force Team. Our tasks include utility coordination and oversight on traffic signal, lighting, signing and pavement markings.


“EDSI’s employees bring value to the team exhibit the values that I-64 project leadership was looking for to make the project successful: be flexible, encourage risk and accept failure, empower employees, be safe, provide best value for money spent, use teamwork, listen and seek to understand, seek out and welcome ideas that increase options, and strive to work better, faster, and cheaper. EDSI meets expectations for this evaluation period.” Lesley Hoffarth, PE, Project Manager



State Route 23 Roadway Expansion

Location: Ottawa, Illinois

EDSI was selected as a sub-consultant for a $4 million construction project for new roadways and improvements to existing roadways in Ottawa, Illinois.


EDSI provided project management and design of construction plans for 3,739 feet of new roadway and 7,506 feet of improvements to existing roadway to accommodate a commercial development. Existing roadways that were widened included Dayton Road, Route 23, Stevenson Road, and the I-80 off-ramps. New Roadways included Veterans Parkway and the Stevenson Road extension.


Two separate sets of plans were required, one for the City streets and one for the State routes. Design included temporary and permanent easements, a new right-of-way, alignments, profiles, warping details, open and enclosed drainage design, signing, pavement markings, one new traffic signal, four modified signals, signal interconnect, cross-sections and quantities.



Route 109 Construction Plan

Location: St. Louis County, Missouri

EDSI performed the sub-consultant portion of project management and design of construction plans for coldmilling, resurfacing, and pavement repair on 4.7 miles of roadway. Design included traffic control, quantities, construction cost estimate, and technical specifications.