Project Examples (more coming soon)
Travel Demand Forecasting
Coyote Valley – San Jose, CA
Hexagon Transportation Consultants, Inc. was retained by the City of San Jose to provide transportation planning support for the development of the Coyote Valley Specific Plan. Hexagon was also retained by David J. Powers and Associates to prepare the traffic analysis for the Coyote Valley Specific Plan Draft Environmental Impact Report (DEIR). The study analyzes all elements of the existing and planned transportation system that will be affected by the development of Coyote Valley. The analysis is conducted following the requirements of the Cities of San Jose, Morgan Hill, Gilroy and the Congestion Management Program (CMP) of the Santa Clara Valley Transportation Authority (VTA). Approximately 200 intersections, 30 freeway segments and 15 interchanges are included in the analysis. The tasks in the analysis include: Travel Demand Modeling, Development of Traffic Projections, Evaluation of Traffic Conditions, Mitigation Measures, Development of Alternatives, Mitigation Concept Drawings, Mitigation Cost Estimates and Future Growth Projections.
Hayward Travel Model Update – Hayward, CA
Hexagon was hired by the City of Hayward to update their citywide travel demand model. The model originally was created by Hexagon staff in 1996. The model is a subset of the Alameda County model with additional zone and network detail in the City of Hayward. The purpose of the update was to recalibrate the model to year 2000 conditions using new traffic counts and year 2000 land use data. The model then was used to produce a year 2025 baseline forecast. The forecast was based on ABAG land use projections and MTC’s funded transportation improvements.
Sunnyvale Model Update and Strategic Transportation Program – Sunnyvale, CA
Hexagon was hired by the City of Sunnyvale to update the 2000 Citywide Travel Forecasting Model and the 2003 Transportation Strategic Plan. The original citywide model was implemented in TRANPLAN, relied on 2020 land use projections, was outdated and inconsistent with VTA’s CUBE-based County wide model. Hexagon used the VTA’s countywide model as the basis for updating the citywide model. Additional traffic analysis zones were added within Sunnyvale, the networks were updated and the model was validated for the year 2005. Consistent with VTA’s most recent forecasting projections, ABAG Projections 2007 for the year 2030 were used to develop turning movement forecasts at approximately 50 intersections. An intersection turning movement post processing procedure was develop to adjust the 2030 raw model output based on actual traffic counts and year 2005 and 2030 model estimated volumes.
The preparation of the Transportation Strategic Plan (TSP) entailed (1) evaluating intersection levels of service under existing and future traffic conditions, (2) identifying locations of substandard conditions, (3) devising improvements to mitigate conditions at the substandard locations, (4) estimating the cost of implementing the improvements, (5) identifying funding sources for the improvements, and (6) calculating a proposed traffic impact fee by distributing the total improvement costs over anticipated future development in the City of Sunnyvale. Hexagon is currently in the process of updating the 2003 TSP. In addition to the aforementioned tasks, Hexagon will evaluate if there will be any CMP intersection that cannot be mitigated and would therefore operate at unacceptable standards in the future. In that case, these deficiencies can be addressed by implementing a deficiency plan.
Traffic Simulation
Geneva Extension Candlestick Point/Route 101 Interchange Joint PSR – Brisbane, CA
This project is sponsored by the City of Brisbane. The city has retained Biggs Cardosa & Associates to prepare a Project Study Report (PSR). As a subcontractor to Biggs Cardosa & Associates, Hexagon Transportation Consultants, Inc. is providing various traffic engineering services. Hexagon’s responsibilities include developing future traffic forecasts and conducting traffic operations analyses.
The traffic analysis focused on two potential future scenarios, Alternative 1 and Alternative 2. Both alternatives are variations of a compact diamond, which was chosen by the Project Team because of key right-of-way constraints. The project also includes a significant level of new BRT operations. The BRT operations were specifically analyzed in several configurations in order to minimize the impact of BRT operations on street traffic. Both alternatives were analyzed for AM and PM 4-hour periods (approximately 6 AM to 10 AM, and 3 PM to 7 PM, respectively). The mainline conditions were analyzed using CORSIM developed by FHWA. The freeway mainline operations model for existing conditions was first calibrated and then used to forecast the future traffic operations on the mainline. The traffic operations for the two signalized intersections that would be created on Geneva Avenue/Harney Way as a result of the full-diamond interchange with US 101 were analyzed using SimTraffic (Synchro). The two models were analyzed with consistent assumptions to one another.
U.S. 101/Tennant Avenue Interchange Operations Analysis – Morgan Hill, CA
Hexagon completed an operations analysis as part of the preparation of a PSR/PR for interchange improvements on Route 101 at Tennant Avenue. The City of Morgan Hill is proposing to add capacity to the interchange to accommodate increased traffic volumes due to future growth within the city by constructing one of two improvement alternatives. Both improvement alternatives would serve the northbound peak direction of travel during the AM peak hour.
One alternative would consist of the widening of the Tennant Avenue overpass of US 101 from two to four lanes of travel and construction of a new eastbound Tennant Avenue to northbound US 101 loop on-ramp. The second alternative includes the overpass widening with the addition of a second eastbound Tennant to northbound US 101 left-turn lane. The second alternative would be a less expensive improvement since it is only a modification to the existing freeway ramps, but may not provide the needed capacity to serve projected traffic volumes.
A combination of use of a traffic forecasting model and traffic simulation model were utilized in the evaluation of the planned interchange. The Valley Transportation Authority’s travel demand forecasting model which is consistent with the Metropolitan Transportation Commission’s (MTC) regional forecasting model was used to obtain forecasted traffic volumes because it focuses in a more detailed manner on Santa Clara County. The microscopic simulation program SYNCHRO was used to evaluate any potential operational and weaving problems on the freeway mainline and Tennant Avenue at the interchange due to the projected traffic volumes.
The operations analysis consisted of the evaluation of future land use scenarios with and without the proposed interchange improvements. The operations of the interchange with and without the proposed improvements were based on the future traffic volumes developed with the traffic model. Forecasted traffic volumes for both scenarios are identical with the only difference being the adjustment due to the proposed improvement alternatives. The operations analysis included an evaluation of basic freeway sections, on-ramp merge areas, off-ramp diverge areas, freeway weaving areas, and ramp terminal intersections. In addition, the potential weaving conflicts on US 101 between the Dunne and Tennant Avenue interchanges were analyzed.
The traffic operations analysis indicated that both improvement concepts would provide the necessary capacity at the interchange intersections to accommodate the projected traffic volumes and that both the loop and the double-left turn interchange improvement concepts perform equally well. Therefore, the determination of which improvement alternative will be implemented was to be based upon financial considerations.
Blossom Hill Road Traffic Operations Study – San Jose, CA
Hexagon completed an analysis of traffic operations on Blossom Hill Road in the vicinity of US 101. The purpose of the study was to evaluate the effectiveness of roadway improvements proposed to mitigate the impacts of planned development in the Edenvale Industrial Area. The traffic operations analysis was conducted using the microscopic simulation software, TRAF-CORSIM. CORSIM simulates the movements of individual vehicles through an integrated network of surface streets, freeway ramps and mainline segments. Because of the microscopic level of detail, CORSIM accurately models a driver’s lane preference based on its upcoming turn movement, vehicle lane changing maneuvers (on freeways segments and local streets), actuated signal control, freeway ramp metering and the effects of queuing.
The simulated study area extends from the intersection of Blossom Hill Road and Beswick Drive to the intersection of Silver Creek Valley Road and Hellyer Avenue, including a total of seven signalized intersections. The study area also includes grade separations with connecting ramps to and from Monterey and Cottle Roads. Because of the concern about unbalanced lane usage and weaving, Hexagon took special care to quantify the existing and future weaving movements on critical sections of Blossom Hill Road. The simulation analysis results were presented in two forms. Quantitative measures of effectiveness including average stopped delay, phase failures and queue lengths were reported, and an animation of traffic operations on Blossom Hill Road was presented before multiple City departments.
Milpitas Boulevard Traffic Operations Study – Milpitas, CA
Hexagon Transportation Consultants, Inc. was retained by the Milpitas Boulevard LLC to complete a traffic operations study for a proposed residential development within the Piper-Montague subdistrict of the Milpitas Transit Area Specific Plan (TASP). The proposed project consisted of three different builders and a total of 1,436 residential units. Access to the site would be provided via Milpitas Boulevard and Piper Drive.
The purpose of the traffic operations study was to satisfy the requirements of the City of Milpitas. The operations analysis included a site circulation and access review to determine the adequacy of the proposed site plan in accordance with generally accepted traffic engineering standards, as well as to confirm the proposed project’s overall consistency with the Milpitas TASP. The study included an evaluation of potential intersection configurations and traffic control types for the new public streets within the Piper-Montague area where they would connect to Milpitas Boulevard and Piper Drive. The three project access scenarios that were evaluated for the proposed Street A include the following:
- Signalized intersection – would provide full access to and from Milpitas Boulevard;
- Unsignalized intersection – would allow left turns into the site from Milpitas Boulevard but only right turns would be possible for exiting vehicles; and
- A right turn only configuration with a median on Milpitas Boulevard.
A traffic simulation of Milpitas Boulevard between Gibraltar Drive and Montague Expressway using Synchro software was conducted in order to accurately simulate future traffic conditions on Milpitas Boulevard after completion of the project. The main purpose of the Synchro analysis was to determine the traffic control and design that would be most appropriate for Street A. The simulation was conducted for the AM and PM peak hours under near-term project conditions and Year 2030 conditions with the project. Hexagon worked closely with City staff to develop a two-phased plan line for Milpitas Boulevard. The first plan line would be implemented at the onset of the project (Phase 1). It would allow for unsignalized left turns into and out of Street A at its intersection with Milpitas Boulevard. Phase 2 of the project involved signalizing the Milpitas Boulevard and Street A intersection, which would provide for protected left turns into and out of the project site.
Traffic Safety
Kifer Road Accident Study – Sunnyvale, CA
Hexagon was retained by the City of Sunnyvale to investigate an accident problem on Kifer Road, just east of Lawrence Expressway. The problem segment was experiencing accident rates that were over five times that of the statewide average for similar facilities. The focus of the analysis was on an unsignalized intersection that had illegal U-turn activity and poor sight distance. The study also involved several public meetings. Hexagon analyzed several alternatives, including eliminating the left turn pocket, additional signing and striping, and the installation of a traffic signal.
Milpitas Boulevard Traffic Operations Study (Simulation) – Milpitas, CA
Hexagon was retained by the City of Milpitas to evaluate safety concerns on Milpitas Boulevard, just north of Montague Expressway. The study segment experiences significant congestion because of it’s intersection with Montague Expressway. This congestion creates sight distance problems for vehicles trying to exit from driveways at adjacent properties. Hexagon mapped all of the existing accidents over the past several years and prepared conceptual illustrations of the accidents for City staff. After the problem was understood, Hexagon prepared three potential alternative improvements that could mitigate the accident problem. These included the construction of additional lanes, improvements to sight distance, and the installation of a traffic signal.
Lane Reduction at Walnut Avenue & Argonaut Way – Fremont, CA
Hexagon was retained by the City of Fremont to conduct a lane reduction and roundabout study along Walnut Avenue and Argonaut Way in Fremont, California. The project evaluated the effects on traffic flow and safety of reducing the number of lanes on Walnut Avenue and Argonaut Way from four lanes to two, and installing a single lane roundabout at the intersection of Walnut Avenue and Parkhurst Drive. The study also included a safety analysis of the study segment to determine whether additional safety improvements were necessary.
Ridge Road Traffic Study – Amador County, CA
Hexagon was retained by Stantec Consulting and Amador County to conduct a safety analysis for the intersection of Ridge Road and New York Ranch Road in Amador County. The intersection was experiencing accident rates twice that of the state average. Hexagon identified the key factors contributing to the existing situation and recommended near-term, medium-term, and long-term solutions. Our findings were summarized in report format, and were presented to County Supervisors.
Traffic Signal Design Experience
San Pablo Avenue Pedestrian Improvements – El Cerrito, CA
As a subconsultant to Gates & Associates,Hexagon prepared electrical design plans associated with pedestrian facility improvements at 14 intersections along San Pablo Avenue in the City of El Cerrito. The design plans included traffic signal modifications to accommodate new and upgraded pedestrian traffic signals along with minor signing and striping work for each location. Additionally, the plans included the design for a crosswalk with motion-activated in-pavement flashers and advanced flashing beacons. The plans and specifications were prepared to Caltrans standards since San Pablo Avenue is also State Route 123 through El Cerrito.
McCarthy Boulevard and Tasman Drive Signal Modification – Milpitas, CA
Hexagon Transportation Consultants, Inc. was retained by Fairview Murphy Road LLC to prepare a conceptual improvement plan, striping design, and signal modification for the intersection of McCarthy Boulevard and Tasman Drive in Milpitas, California. The redesign of this intersection is a result of mitigation measures proposed in the Murphy Ranch Road development project. Tasman Drive has light rail facilities within the median which required additional design considerations of traffic signal phasing, wiring, equipment placement, and traffic control cabinet capacity. In addition, the previous traffic signal plan did not have full documentation of existing light rail facilities at the intersection. Hexagon provided complete documentation of existing light rail facilities at the intersection as part of the traffic signal modification per the request of the City of Milpitas. The project was designed in accordance with the City of Milpitas design standards, California Manual on Uniform Traffic Control Devices, 2006 Caltrans Standard Plans and Caltrans Standard Specifications.
Church Street & Tenth Street Signal Modification Design – Gilroy, CA
Hexagon was hired by the City of Gilroy to prepare traffic signal modification plans, signing/pavement delineation plans, civil improvement plans and specifications for the proposed reconstruction of this intersection. For this project Hexagon prepared plans for the modification of an existing traffic signal at the intersection primarily to accommodate protected left-turn phasing on the Church Street approaches. However, during the course of the signal modification design, the City determined that it would be necessary to replace all four existing curb ramps at the intersection with new ADA-compliant curb ramps. As such, Hexagon hired HMH as a sub-consultant to perform the civil improvement design for the new curb ramps and curb and gutter work at the corners. Additionally, HMH prepared the design for new curb, gutter, and sidewalk for a 220-foot portion of Church Street on the northeast corner of the intersection. The intersection improvements also included pavement rehabilitation within the intersection and on the north leg of the intersection. HMH prepared the construction staging and traffic control plans for the pavement work and curb and gutter work at the intersection.
Because of the extensive work at the corners required to accommodate ADA-compliant curb ramps, all of the existing signal poles needed to be removed and replaced with new signal poles and the controller and services cabinets needed to be relocated. This intersection is in a built-up residential area, which leads to significant challenges in terms of locating the new signal poles because of existing utility conflicts, right-of-way constraints, and existing signal pole locations. Hexagon worked closely with the City inspector, the electrical contractor, and the City engineer to “field-fit” the new signal poles and resolve all conflicts.
Construction on the signal and civil improvements was recently completed and the signal is fully operational.
Webster Street and Stargell Design – Alameda, CA
Hexagon was hired as part of a team to provide a design for a major new road connection in the City of Alameda. In addition to the new road, the project included modifications to two existing intersections. Modifications included the addition of bike lanes, widened sidewalks, and pedestrian-scale lighting. Hexagon provided electrical design, both for traffic signals and street lights and also provided signing and striping designs and traffic handling plans for construction. The project involved review and coordination with Caltrans because Webster Street is a state highway.
Julian Realignment Signal Designs – San Jose, CA
Hexagon was hired as part of the team to prepare a new street plan for a part of downtown San Jose near Julian and San Pedro Streets. This is a redevelopment area. The San Jose Redevelopment Agency wishes to make the area more walkable and prepare it for residential development by realigning an existing arterial street that carries a high volume of fast-moving traffic. Design challenges include how to replace the traffic capacity but in a narrower cross section and how to develop safe pedestrian crossings. Hexagon prepared designs for two new signals and two signal modifications. Hexagon's scope of work also includes enhanced designs for signing, striping, and street lighting.
On-Call Experience
Sunnyvale As-Needed Services - Sunnyvale, CA
Hexagon staff has twice been hired by the City of Sunnyvale to provide on-call traffic engineering and planning services. With the first contract, the issues investigated were: determining the feasibility of closing an on-ramp along Central Expressway, the feasibility of reducing the number of lanes on Mary Avenue and adding bike lanes, and feasibility of removing parking stalls and adding bike lanes on Homestead road. The studies involved data collection, analysis, mitigation, and attending meetings with residents, motorists, and members of the Bicycle Advocacy Committee.
With the second contract, Hexagon assisted the City of Sunnyvale staff with a variety of local transportation engineering problems. These included parking studies, pedestrian studies, bike lane studies, lane reduction studies, road closure studies, and studies to determine the appropriate traffic control devices. These studies have required Hexagon staff to prepare graphics and striping plans, prepare work orders for corporation yard staff, review traffic counts conducted by technicians, attend neighborhood meetings, conduct level of service calculations, conduct crosswalk studies, coordinate with other departments such as Public Safety, prepare reports to the City Council, estimate future traffic patterns, evaluate potential transportation impacts, asses the need for signal modifications, oversee project implementation, and conduct follow-up studies as needed.
Parking Studies
The Alameda Parking Study - San Jose, CA
Hexagon prepared a parking study for The Alameda neighborhood commercial district for the San Jose Redevelopment Agency. The Alameda is an older strip commercial area that has a mixture of high-quality buildings suitable for rehabilitation and reuse and large lots available for new uses. The redevelopment agency is encouraging development along The Alameda that will result in a successful retailing and restaurant center. One major issue is how to provide adequate parking. Many of the older buildings are on lots that have no room for parking spaces. These businesses rely on street parking. Hexagon conducted numerous surveys of parking occupancy, including weekdays, nights, Saturdays, and during San Jose Sharks games, when this area is affected by arena parking. Hexagon made several recommendations for both short and long-term parking improvements. These included better signing and marking of spaces, revising some time limits, restriping and enlarging some existing lots, and obtaining parking agreements between businesses.
