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

​EMERGENCY RESPONSE!  Fire Engine Response Study.    Feb 2019, Fairfield, CA
PRISM Engineering conducted a comprehensive emergency fire engine response time study to determine if adequate emergency response times are in place according to established standards (NFPA 1710). Out of nine nearby fire stations, 3 were within the standards, and only one needed to be. A complete report with tables and graphics was prepared to document all findings, and detailed times on all travel paths. Google Maps App was also researched to make comparisons of actual drive times in the field, and to verify.    The purpose of the study was to find out through engineering methods (research, measurements, analysis, and summary) what fire engine response times from various fire stations proximate to the project site would be, by physically measuring and video recording actual driving times from each station to the site, adjusting times for red lights along the way, considering the effects of traffic congestion, and taking into consideration what happens when a fire engine deploys traffic signal pre-emption to bypass a red light at an intersection, etc. In addition, “big data” from Google Maps was also used, a publicly available data set that documents the ranges of time that drivers experienced along a certain path while using the Google Maps App.  A detailed info-graphic and summary matrix and report were prepared to show optimum pathways and times from nine different nearby fire stations to the project site, during the “worst case” pm peak hour time period.

-ON-CALL SERVICES-

In Marin County:  Four Corners Intersection, Improvement Alternatives (2017-2019)
                                 Panoramic Highway at Muir Woods Road

Observations. Video. Sight Distance. Synchro. Intersection Design.
Traffic Calming. Reduce Accidents. Increase Safety.

FOUR CORNERS work_order_report.pdf
File Size: 38729 kb
File Type: pdf
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SAFETY FIRST

MARIN COUNTY ON-CALL SERVICES. Jan 2019
​Four Corners Intersection: Final Alternative.
Traffic Engineering.

Engineering design and drawing by Grant Johnson, TE Registered Traffic Engineer © 2019
Work completed for Marin County Department of Public Works.

COMMENTARY ON IMPROVEMENTS BY GRANT JOHNSON, TE :

  • This intersection will undergo a huge safety and design improvement. Traffic will slow significantly to about 20 mph.  Traffic operations will improve with a focused intersection. Bikes can safely navigate, etc.
  • The deflection angle for the NB approach matches deflection angle used in single lane approach or dual lane approach modern roundabouts and as published in the MUTCD. This angle has a traffic calming influence. It will slow traffic to safe speeds, such as 20 mph. The radius of the approach entry curve is 100 feet.  This also applies for the southbound movement, but the curve is on the exit.
  • Striped islands are being used, with thick wide lines to clearly delineate the area that should not be used.  
  • The centerline of the SB approach has been modified to expand to a short loop area about 3 feet wide and then tapering back to the center, providing some better definition for the vehicle pathways.  All vehicle pathways have been checked, are tangential to the lane curves, centerline striping and edgeline striping at intersection approaches clearly directs vehicles in a smooth and logical path.  It has been designed for smooth movement of vehicles, through 12 foot wide lanes.
  • The turns in the intersection according to the proposed striping shown, have been tested with the Caltrans HDM truck turning templates for a large bus and pass the test.
  • The Muir Woods EB approach has been significantly moved forward, as well as the WB approach.  Stop signs have been relocated. It is possible to see previous markings through the slightly translucent black overlay layer.
  • The Panoramic Highway NB approach has also been moved forward significantly, and the length of the left turn pocket has increased from and existing 115’ to 140’ with the proposed striping.  The intersection as a whole is much tighter together.
  • The warning signs proposed will guide drivers that a 20 mph advisory curve is at hand.  
  • The centerline striping for the NB and SB approaches has been extended through the intersection according to the MUTCD standards on Fig. 3A-112(CA).  This also serves as a kind of refuge for the left turns out from NB Panoramic Highway.  
  • The NB approach and the SB approach have both been modified with Speed Reduction Markings for the through lanes. MUTCD Fig. 3B-28 details the size and spacing of the markings, and this plan has been implemented accordingly.  These markings should be sufficient to alert drivers that a slowing in speed is expected, and with the warning sign clearly in place at the end of the markings, drivers should have slowed to 20 mph, according to the curve and deflection implemented. It is possible to also install rumble strip traffic calming devices, but not necessary if these other devices are installed.

AERIAL VIEWS and
​NEW INTERSECTION DESIGN

SIGHT DISTANCE and SPEED STUDIES

International 国际 Highlight

Traffic Engineering
TRAFFIC OPERATIONS:  MICROSIMULATION TRAFFIC MODELING 
Since 1995 when it was first released, PRISM Engineering has been using Synchro and SimTraffic to analyze traffic and design signal systems.  
PRISM has also used many of the other microsimulation software packages in existence today, but prefers the SimTraffic software because it is 1) Ubiquitous, 2) Not easily manipulated to get significantly different results from default setup, 3) Works with Synchro and all the specific lane geometry and traffic operations data already in that software, and is readily shared with clients.
​In this infographic example, Grant Johnson, TE emphasizes multiple levels of information in a simple graphic, showing street aerials with volume-based HCM level of service composited, actual freeway traffic flows, color coded travel paths (red=stop and go LOS F, green=free flow LOS D or better), and microsimulation level of service shown on long paths of stop and go flows.

PRISM Engineering creates detailed and accurate microsimulation and analysis models.  We collect "Big Picture" data to see the big picture.

Synchro / SimTraffic

​Using industry standard microsimulation software like Synchro and SimTraffic, Vissim, and Paramics, our analysis approach is to have high levels of detail to facilitate better answers that mirror how the public already perceives their traffic experience.
​ PRISM knows that reporting "LOS C" when the public is experiencing LOS E or F is a big mistake, and that analysis tools must reflect reality.  That is why we collect data with aerial and street level VIDEO and also take Saturation Flow Rate samples to better understand local driver behavior and adjust software accordingly.
​photo/video © 2019 PRISM Engineering
PRISM Engineering routinely hires outside services to collect big picture data, and regularly collects / films aerial video in 4K resolution in order to study and analyze real world traffic conditions as a system of intersections and driveways, and not as isolated intersections.  This data used in our consulting practice enables an understanding of the bigger picture which can not be obtained from analyzing traffic count data alone.

Traffic Engineering
DETAILED INTERSECTION ANALYSIS and DESIGN, based on TRAFFIC PROJECTIONS

-ON-CALL SERVICES-

In the City of Vacaville:  The Farm at Alamo Creek TIA (2017)
                                            750 unit planned Specific Plan Development

CUBE model. Synchro. HCS Freeway. SimTraffic. Intersection Design.

The Farm at Alamo Creek TIA.pdf
File Size: 54898 kb
File Type: pdf
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Report Samples. Trip Generation. CUBE 6.4 Traffic Demand Model. Excel Database. Synchro HCM Analysis. Mitigations

Traffic Engineering
MICROSIMULATION MODELS to SIMULATE REAL TRAFFIC FLOWS after calibration



​Synchro
and
SimTraffic
PRISM Engineering has worked with numerous cities and county and regional agencies in preparing a variety of traffic studies nearly all using the Synchro / SimTraffic software package because we can share files with reviewing government agencies during the review stages of the study.  We have completed over 100 traffic studies in Nevada County, Placer, El Dorado, Amador, Calaveras, Tuolumne, Madera, Fresno, Merced, San Joaquin, Solano, Sacramento, Yolo, and Contra Costa Counties.  In addition, we have completed numerous studies in various cities such as Vacaville, Dixon, Davis, Lodi, Stockton, Grass Valley, El Dorado Hills CSD, Jackson, Angels Camp, San Andreas, Los Banos, Fresno, Clovis, Folsom, Placerville, Nevada City, Auburn, Truckee, South Lake Tahoe, etc.
A SimTraffic network created by Grant Johnson, TE in Marin County at US 101 and SR 131 interchange is overlaid onto an aerial photograph in SynchroPro / SimTraffic microsimulation software.  Four signalized intersections are coordinated with signal cycle offsets.  These models are used to examine changes in signal timings to get better operations results. They can also be used to examine new roadway and driveway connections, expansions to intersections and changes of lane geometry, etc.  In this study it was determined that signal timing changes could reduce delays and change an LOS F condition for a frontage road side street to LOS D conditions without significantly impacting other movements.

Traffic Engineering
TRAFFIC IMPACT STUDIES and ANALYSIS​
PRISM Engineering staff has conducted numerous traffic impact studies, large and small, over the past two decades.  
TRAFFIC IMPACT STUDY: City of Vallejo, CA Charter School Alternatives Analysis.  Examined: 
  • Traffic Demand Management
  • Intersection Mitigation
  • Phasing of School Growth
  • Future Level of Service Analysis
  • Microsimulation Check Technology
traffic_study_final_vallejo_charter_school_4.pdf
File Size: 4844 kb
File Type: pdf
Download File
CORRIDOR STUDY:

City of Folsom, CA
​Riley Blvd Corridor Study
  • Alternative Median Treatments. 
  • Calming of Traffic
  • Enhancing Safety
CAD based drawings and renditions created by PRISM Engineering

Traffic Engineering
SIGNAL DESIGN

BUILT: El Dorado Hills Green Valley Road Corridor Signal and Interconnect Design by PRISM Engineering

In this On-Call Services work order, PRISM Engineering worked directly with El Dorado County Department of Transportation Design Staff to create the signal design layers in the extensive AutoCAD design file with XREF overlays. Grant Johnson, TE was project manager of this work effort and designed the conduit runs, pole and detector locations, signal phasing and diagrams, signing and striping.
PRISM Engineering has completed numerous signal design projects over the years, and integrated these plans with development applications where street and intersection improvements are required as a part of a traffic impact analysis.  PRISM has the ability to take things from the planning stage of forecasting traffic, to the analysis stage of determining intersection and road segment improvements, and warranting of traffic signals for a new installation, or the modification of an existing signal expanded to include more lanes, etc.  We have also designed inter-connected signal installations where traffic volumes between intersections are coordinated with offset signal cycle timings, and analyzed using SynchroPro and SimTraffic microsimulation.

International Highlight Project in 重庆市 ChongQing, China

Signal Timing and Capacity Throughput Research Study in ChongQing China's Jie Fang Bei's Winding Mountain Road Intersections.  6 Camera Angles of each Phase and Movement.
videography and edit: G. Johnson

Traffic Engineering

PUBLIC PRESENTATIONS, sample
http://www.marincounty.org/depts/bs/meeting-archive
In this case he spoke before the Marin County Board of Supervisors on a hotly contested and controversial topic and discussed the traffic operations study results, and how information was shared with Caltrans, etc.
Link to local newspaper story on this BOS decision and process:
 story: http://www.marinij.com/article/NO/20160413/NEWS/160419920
Grant Johnson, TE has extensive experience in making public presentations on technical topics, and in making them understandable and credible.  

6. Data Collection using HD video and Digital Counters
Website Copy and Media © 2016-2023 b y Grant Johnson, PRISM Engineering