CORE SERVICES

WHAT DIFFERENTIATES
​PRISM ENGINEERING?

ATTENTION TO DETAIL.

Grant P. Johnson, TE and Principal of PRISM Engineering is passionate about getting things right, emphasizing transparency, and attention to the details.  It is our core philosophy and approach that all of our products will be easier to read and understand, be transparent, etc., in order to build bridges of communication.  We take the extra time to make infographics that communicate results, along with supporting text and tables.  

the following services are offered by PRISM Engineering...

1. Traffic Engineering Finding Solutions for Long-Standing Safety and Capacity Problems

PRISM Engineering uses creativity to come up with concepts and eventually, solutions to some of the existing problems where transportation design and traffic control has not kept up with growth.  In the example below, the existing condition is limiting access to an important side street, and enables unsafe maneuvers for drivers attempting to exit towards the signalized intersection.  Our concepts incorporate the side street into the bigger picture with shared traffic control.

SAFETY.   Above all else, Safety is the first priority with Grant Johnson, Traffic Engineer. 

​Regularly examines safety of transportation systems and traffic control devices...with INTERNATIONAL EXPERIENCE including China, to determine if the installations are safe, normal, and customary.  Was common sense used?  Was the traffic control installation  standard according to AASHTO, MUTCD, or State and Local Standard Plans?

An extension of Traffic Engineering, Expert Witness research and testimony are about intimate knowledge of the regulations and details, documentation, and precedent.

Grant P. Johnson, TE is a registered Traffic Engineer in the State of California, the only state in the union with this special distinction.  Now a requirement of many government jurisdictions to qualify traffic studies, the Traffic Engineer is being asked to sign documents as an authority on the subject of all things pertaining to traffic and regulation.  In Expert Witness testimony and research, the title of Traffic Engineer enhances credibility.   ​
    
​He is currently working on several cases as an Expert Witness throughout Northern, Central, and Southern California cities and counties, including working with Caltrans.
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report

PROJECT HIGHLIGHT: Aerial Videography used in Traffic Impact Study with 2 Freeway Interchanges

In County of Eldorado, Cameron Park:  Country Club Apartments (affordable housing) Traffic Impact Study, Operations Analysis (AUGUST 2022)

This study includes a comprehensive Traffic Impact Study complete with intersection operations analysis for 10 intersections.   In the video below, the Cameron Park interchange and surrounding intersections are shown for the pm peak hour traffic on a weekday.  All intersection counts were taken from this video for accuracy.
PRISM developed checked the site plan using our CAD tools and truck turn templates to see if apartment site parking lot could handle large trucks or fire trucks.
PRISM developed significant improvement concepts to an existing design (shown in color lines and overlays of lane channels for photos above and below).
PRISM developed precise and accurate turning movement counts from aerial videography, a new and innovative method to get the best traffic data, unlike manual counts where multiple people count, possibly at different times or days, and yielding volumes that need to be balanced manually. With videography from the sky, it is balanced.

PROJECT HIGHLIGHT: Expert Witness Traffic Engineering & Design

In Marin County:  Four Corners Intersection Improvements (2017): Panoramic Highway

work_order_report_draft7pdf.pdf
File Size: 38729 kb
File Type: pdf
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PROJECT HIGHLIGHT: Signal Design Modification and Signing and Striping Plans

In City of Vacaville, Solano County: 
STRADA 1200 apartments, a Guardian Capital project 
Intersection Modification.  Signal Design Modification. Signing/Striping Modification

New Signal Plans: Year 2019 (prepared by PRISM Engineering)

New Signing and Striping Plans: Year 2019 (prepared by PRISM Engineering)
Project Scope:
Intersection converted from 3-way T-intersection to a full access four approach intersection. New road constructed.
​PRISM conducted a complete inventory and inspection of Signal Equipment, signing, and striping / pavement markings. Surveyed pedestrian activity.
Photos and video logging.
New signal heads needed.
Complete replacement of video detection to latest tech. Revised striping. New Crosswalks needed. Signing revised.
​Signal interconnect maintained between local intersections. 
​---New signal plans needed for bid. 
---New signing and striping plans needed for bid.
---Equipment Schedule completely revised.

New Signal / Striping Plans: Year 2019

       source: PRISM Engineering

25 year old "As-Built"
(original signal design)

       source: Vacaville Public Works

Our Traffic Engineering services are comprehensive, including Traffic Counts by UHD Video, Spot Speed Surveys, Signal Design, Signing and Striping, Capacity Analysis (Synchro/SimTraffic), Traffic Operations Studies and Microsimulation analysis, Traffic Calming, Complete Streets, and Parking Studies, etc. 

3. Transportation Planning Helping to Accommodate Smarter Growth in Communities

PRISM Engineering uses creativity in all aspects of Transportation Planning, even in Traffic Demand Models (TDM) where innovative features are incorporated to enhance communication and results.  For example, smaller TAZs and more including all streets and transit networks, even pedestrian traffic.  Multi-modal analysis is possible.  Changes to traffic patterns is possible to document and analyze, verify the soundness of alternatives.  Our Traffic Impact Studies incorporate output from the local TDM and merge this information seamlessly with real traffic count data that can be analyzed using sophisticated tools including microsimulation which takes into account the details.  Attention to detail.  Our analysis results are a hybrid of standard cook book methods (HCM) with custom microsimulation methods (ie SimTraffic which merges with Synchro for HCM).  This two-step approach lets us consider all modes of traffic and better inform the process of project approval and sustainable mitigations.

Road diets, multi-modal conversions,
IINNOVATION that opens up possibilities.
​Analysis of changes verified to work.
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report

PROJECT HIGHLIGHT: Cube Voyager Traffic Model used in
                                     large Transportation Planning Study

In City of Vacaville, Solano County:  The Farm at Alamo Creek Specific Plan
Traffic Impact Study, Operations Analysis, and EIR Section, (2017)

Picture
This study includes a comprehensive Traffic Impact Study complete with intersection operations analysis for 20 intersections, 18 roadway segments and 5 miles of freeway operations analysis. 


The first step in this scope of work was to update the City of Vacaville's Cube Voyager general plan traffic model, add new road systems, new traffic analysis zones for the project, and run the model to generate Existing plus Approved plus Project volumes as well as Cumulative year 2035 volumes.   The project was a mixed use of residential development, commercial development, and regional park.

Mitigations
Mitigations were developed in collaboration with the City Traffic Engineer.  Solutions were sought where capacity enhancements could be achieved without right-of-way takes.

PROJECT HIGHLIGHT: Transportation Planning

In El Dorado County:  Dorado Oaks Residential Development in Diamond Springs Traffic Impact Study and Operations Analysis (2016-2022)

This study includes a comprehensive Traffic Impact Study, a Traffic Operations Analysis and Micro-simulation model(s) for the Missouri Flat Road corridor from Plaza Drive to SR 49 Pleasant Valley Road (2 miles).  Multiple scenarios were analyzed for Year 2017, 2025, and 2035 conditions with and without the project.  Detailed analyses were performed using calibrated micro-simulation SimTraffic models, and mitigation measures explored along with the future Diamond Springs Parkway bypass in the Travel Demand Model network.
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