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Our Story

Bill

Founded in 1985 by William “Bill” Gray, Gray-Bowen-Scott is a professional consulting firm specializing in the delivery of transportation projects in the Greater Bay Area.

The Beginning

Bill’s career started with the Contra Costa County Public Works Department, as a junior engineer. He quickly moved his way up to Deputy Public Works Director, where he enjoyed working closely with the Board of Supervisors and other federal, state, and local officials on complex regional transportation and land development issues. His funding and political strategies made the delivery of the Pleasant Hill BART station and the reconstruction of I-680/24 Interchange possible, and Bill helped shape the way the county adapted to the post-Proposition 13 environment. Starting his own firm to help people traverse the complex political, policy, funding, and design challenges that projects encounter was a natural evolution of his career. Public and private sector clients sought his strategic and creative methods for delivering projects in a technically feasible and politically acceptable manner.
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In 1986, remembering her collaborative problem-solving skills from working with her at the County, Bill invited Terry Bowen to join him. Utilizing their unique skills and relationships, they tackled and successfully delivered some of the Greater Bay Area’s most high-profile and diverse projects: the passing of the first-ever, and highly controversial, ½ cent sales tax measure, the replacement of the obsolete Maxwell Bridge on State Route 121 in Napa, the Sunol Grade HOV lanes, and a landmark bicycle-pedestrian overcrossing at I-80 and University Avenue in Berkeley, to name a few. As they grew the company, Bill and Terry, with young families of their own, were committed to providing a balanced life environment, and to afford their staff with opportunities to grow and succeed.

Drawn by Bill and Terry’s accomplishments, enthusiasm, and work style, Leo Scott joined Bill and Terry in 2004 after a 16-year career with Caltrans. Leo brought new capabilities to the company and was instrumental in developing an innovative partnership arrangement between Caltrans, Alameda and Contra Counties that made construction of the 4th Bore of the Caldecott Tunnel possible. He also pioneered the development and delivery of the Bay Area’s first-ever Express Lanes projects. In 2014, the company became Gray-Bowen-Scott.

Today

Today, Leo Scott is leading the team as President. Bill Gray has retired from day-to-day activities while remaining on the Board of Directors. Terry Bowen is still actively involved while working on her bucket list. The culture and values instilled from the beginning are strongly embedded in GBS today.
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With a larger team of seasoned and accomplished professionals, Gray-Bowen-Scott is engaging in bigger and more challenging projects than ever before, all of which benefit the communities in which we live and work. Presently we are working to deliver the Bay Area’s two largest Express Lanes projects – US-101 and Innovate 680, as well as noteworthy land development projects like the expansion of Adobe’s campus and the world-class San Francisco Conservatory of Music which keep us close to our roots. We’ve enhanced our capabilities by adding Agency Administration to our range of services, providing extension of staff managing last-mile shuttle services for Emery Go-Round and MV-Go, as well as the Transportation Partnership and Cooperation (TRANSPAC.)

We are honored by our clients who’ve entrusted us to deliver some of the most dynamic and innovative projects in the San Francisco Bay Area. We take great pride in the fact that our business is based largely on repeat customers and client referrals. As we look to the future, we acknowledge our entire staff for laying the foundation on which to build upon our success, and for preparing us to contribute to the exciting future of transportation infrastructure in the Bay Area.

Awards and Recognition

Caltrans-01

Caltrans 2021 Partnering Success in Motion Award

EastyBayLeadershipCouncil-01

East Bay Leadership Council Civic Leadership Resolution

ContraCostaCounty

Contra Costa County Board of Supervisors Resolution 91/237 Congestion Relief

CaliforniaAssembly-Seal-01

California Legislature Assembly Resolution 30 Years of Service

ContraCostaCounty

Contra Costa County Board of Supervisors Resolution 2009/0003 25 Years of Service

US-House-of-Representatives-01

Representative George Miller Recognition I680/24 Interchange

Our Team

Leo_Scott

Leo Scott, P.E.

President

Leo Scott, P.E.

President

Leo Scott wears two hats at Gray-Bowen-Scott.  He is both the company President, and Project Manager for several Bay Area Express Lanes Projects. Leo has served as either the Deputy Project Manager or Project Manager for six of the Bay Area’s first ten Express Lanes: Alameda 680 over Sunol Grade, SR 237 Express Lanes at I-880 (awarded project of the year by the California Transportation Commission in 2013), Contra Costa 680 Express Lanes through the San Ramon Valley, Alameda 880 Express Lanes, and Contra Costa 680 Express Lane north of Walnut Creek. Leo is well versed with what is required to deliver an Express Lane project from conception to completion and has applied that knowledge and experience to help co-lead the San Mateo 101 Express Lanes Project.  As President of Gray-Bowen-Scott, Leo provides strategic leadership by working with the Board of Directors and the Management Team to establish long-range goals, strategies, plans and policies, and to direct and evaluate the organization's fiscal function and performance.   Leo holds a Bachelor of Science, Civil Engineering, Stanford University, and a Master’s Degree in Public Administration, University of San Francisco.

When Leo is not here at GBS, he enjoys:

  • Cultivating his garden
  • Building houses in Mexico
  • Serving as a member of his church’s board

Email Leo

Terry_Bowen

Teresa Bowen, P.E.

Principal Project Manager

Teresa Bowen

Senior Project Manager

For over 40 years, Terry Bowen has helped over a hundred complex transportation and land development projects come to fruition. Utilizing collaborative partnerships with various stakeholders including her local government relationships, Terry helps her clients navigate “the system.” Whether she's securing approvals of environmental documents, right of way certifications, design plans, encroachment permits or obligating state or federal funds, Terry has spent decades developing respected relationships through trust and collaboration with Caltrans, FHWA, CTC and regional transportation agencies. Terry holds a Bachelor of Science in Civil Engineering from the University of California, Berkeley.

When Terry is not here at GBS, she enjoys:

  • Dance classes
  • International learning and discoveries
  • Searching out tasty red wines
  • Spoiling 4-legged furry friends

Email Teresa

Karen_Boggs

Karen Boggs

Operations Manager

Karen Boggs

Operations Manager

Karen is the Operations Manager of Gray-Bowen-Scott’s two Transportation Management Associations in the cities of Emeryville and Mountain View. In this key role, Karen oversees and manages the shuttle operations contracts for two shuttle services (Emery Go-Round and MVgo) while providing critical support to the Executive Director.

When Karen is not here at GBS, she enjoys:

  • Enjoys laughing and making others laugh
  • Is a full believer that “Happiness is a Warm Puppy” (Charles Schultz)
  • Is passionate about interior design and making spaces beautiful
  • Loves wine and dirty martini’s and secretly would love to try bartending

Email Karen

Debby_Chernila

Debby Chernila

Project Analyst

Debby Chernila

Billing Specialist

Debby provides vital accounting support to the Project Management team. Debby’s extensive experience allows her to proactively monitor project budgets and identify potential budget risks. Debby is responsible for preparing all of Gray-Bowen-Scott’s monthly invoices with a high level of accuracy and attention to detail. Debby also utilizes our program management information solution (PMIS), e-Builder®, to enter project invoices and project information. Debby holds a Bachelor of Arts in Film and TV Production from Pennsylvania State University, State College PA.

Fun Facts:

  • Won a car on Wheel of Fortune in the bonus round!
  • Treasures the tradition of an annual “sister’s trip” with her four sisters.
  • Taught backgammon as a way to earn money in college.

Email Debby

Chris_Doerksen

Chris Doerksen, P.E.

Project Manager

Chris Doerksen, P.E.

Project Manager

Chris has over 10 years of diverse experience in the transportation industry. Chris’ contributions include collaboration with MTC to complete the PA/ED for Phase 1 of the Regional Express Lanes Network. When complete, the project will convert 76 miles of existing HOV lanes to Express Lanes for five separate highway segments in Contra Costa and Alameda Counties. Chris has worked on a variety of projects that involve coordination with public agencies, managing project schedules, and budgets, and Chris has technical experience in utility improvements, stormwater control plans, streetscapes, interchange improvements, and traffic handling. Since joining Gray-Bowen-Scott, Chris has partnered with Terry Bowen to help our clients to secure permits from Caltrans to keep their projects on track. Chris holds a Bachelor of Science in Civil Engineering from the University of the Pacific.

Email Chris

Doi, Grace 3

Grace Doi

Associate Project Manager/Grant Writer

Grace Doi

Associate Project Manager/Grant Writer

For seven years, Grace worked as a Technical Writing Consultant at San Joaquin Regional Transit District (RTD), where she was responsible for training and coaching staff in all levels of business writing and communication. There, she gained experience in grant writing and is applying that knowledge in her current role with Gray-Bowen-Scott. Prior to the transit industry, Grace has worked in marketing and as an instructional designer and adjunct faculty at post-secondary institutions. With a high aptitude for learning, she enjoys finding creative solutions to problems and fine-tuning writing (and processes) for optimum effectiveness and efficiency. Grace holds a Bachelor of Arts in English Literature from University of California, Los Angeles and a Master of Arts in English Literature from University of Illinois at Chicago.

When Grace is not working, she enjoys:

  • Engaging in deep conversations with her friends and family
  • Singing and playing music with her family
  • Advocating for all vegetables (she hasn’t met one she doesn’t like)
  • Teaching fitness classes (Spin and Bodypump)

Email Grace

Tiffany_Gephart

Tiffany Gephart

Project Analyst

Tiffany Gephart

Project Administrator

Tiffany serves as Gray-Bowen-Scott’s Board Clerk and Project Administrator. In this role Tiffany provides support to the two Transportation Management Associations and Transportation Partnership and Cooperation (TRANSPAC) Boards through her preparation of agendas, staff reports, and meeting minutes. Tiffany interacts directly with members of all three Boards and is adept at relating with elected officials and stakeholders alike. Tiffany also provides administrative support to the TMA and TRANSPAC Directors by assisting in the operations of each organization. Tiffany holds a Bachelor of Arts in Political Science from Pitzer College and a Master’s Degree in Public Administration from San Francisco State University.

When Tiffany is not here at GBS, she enjoys:

  • Calligraphy and all things crafty
  • Weight training and outdoor activities
  • Watching movies with her daughter and husband (most notably Harry Potter and Nacho Libre)

Email Tiffany

Carlin_Gill

Carlin Gill

Chief Financial Officer

Carlin Gill

Controller

Carlin brings more than twenty-five years of finance, accounting, human resources, and general management experience to the Gray-Bowen-Scott team. She’s served as the Chief Financial Officer of several science, engineering, and technology firms ranging in size from small start-ups to publicly traded, multinational corporations. Carlin strives to continuously improve business efficiency at Gray-Bowen-Scott so that our project managers and other professionals can focus 100% of their attention on providing innovative solutions to our clients. Carlin holds a Bachelor of Science in Accounting from Arizona State University.

Outside of the office, Carlin:

  • Has two teenage sons playing tournament baseball (which she loves watching with her husband and keeping score with Gamechanger)
  • Enjoys gardening, raising chickens, being outdoors, reading, and spending time with her family

Email Carlin

Carl_Hacck

Carl Haack, P.E.

Principal Project Manager

Carl Haack, P.E.

Senior Project Manager

As a Senior Project Manager, Carl Haack provides leadership and oversight to Gray-Bowen-Scott’s dynamic team of project managers and analysts. With over 25 years of experience delivering transportation programs and projects in the Bay Area and California, our team and our clients benefit from Carl’s deep regional and project delivery roots. Carl holds a Bachelor of Science, Civil Engineering, Old Dominion University.

When not working, Carl enjoys:

  • Hanging out with family and friends
  • Exploring the Western US and hiking, fishing, and camping
  • Traveling around the world
  • Fly fishing (did I mention that already!?!)

Email Carl

Roni_Hattrup

Roni Hattrup

Senior Program Manager

Veronica “Roni” Hattrup

Senior Program Manager

Roni Hattrup has extensive agency operations and financial management experience in the transportation industry. Roni currently serves as the Executive Director of the two Transportation Management Associations (TMA's) which provide “first and last mile” shuttle services in the Cities of Emeryville and Mountain View. She is the primary lead for both non-profit organizations, managing all aspects of the systems according to the bylaws and administrative policies. Roni assists both Boards of Directors in actualizing their visions to provide transportation demand services (TDM).

When not in the office, Roni enjoys:

  • Camping adventures with family and friends
  • Mom and daughter dates with her tween
  • Family and friends game nights

Email Roni

Erin_Heltne

Erin Heltne

Project Controls Manager

Erin Heltne

Project Controls Manager

As Project Controls Manger, Erin provides expert technical support on all of Gray-Bowen-Scott’s high-profile, multi-funded highway projects. With great skill and competence, Erin manages project risks by using quantifiable metrics to identify and mitigate issues before they impact projects. Erin leads the deployment of our new program management information solution (PMIS), e-Builder®, used by our public agency clients for capital planning, and cost management and controls. Erin holds a Bachelor of Arts in Economics from the University of California, Los Angeles.

Email Erin

Obaid_Khan_64A4704

Obaid Khan, P.E.

Senior Project Manager

Obaid Khan, P.E.

Senior Project Manager

Obaid Khan is a registered civil engineer with over 28 years of professional experience in municipal civil and transportation engineering. He has in-depth knowledge of transportation funding in California. Obaid has worked on many projects where he acquired funding from multiple federal, state, and local funding sources. He has worked with residents, community groups, and political entities on numerous projects to achieve public support. His problem solving and collaborative approach has enabled him to achieve success on controversial local and regional issues. Wherever he has worked, Obaid has established a teamwork environment with a focus on efficient use of public funds. His leadership style facilitates an open and collaborative atmosphere among his staff.  Because he is well respected by his colleagues in the industry, Obaid serves on a number of regional transportation and traffic advisory committees.  Obaid holds a Master of Science, Civil Engineering/Transportation Engineering from the New Jersey Institute of Technology and is affiliated with the Institute of Transportation Engineers (ITE).

When Obaid is not here at GBS, he enjoys:

  • Teaching at UC Berkeley’s Institute of Transportation Studies as an adjunct instructor. Obaid teaches various courses on transportation engineering and planning, including the preparation course for transportation professionals seeking to become a Professional Traffic Engineer in California.  
  • Backpacking, Bicycling, Kayaking, and Fishing
  • Cooking

Email Obaid

debi

Debi Lawrence

Project Analyst

Debi Lawrence

Project Administrator

Debi serves as Gray-Bowen-Scott’s Project Administrator for two Transportation Management Associations (TMAs): ETMA for the City of Emeryville (Emery Go-Round) and MTMA for the City of Mountain View (MV-Go). In this role, Debi’s administrative proficiency and her ability to interact with stakeholders and vendors alike contribute to the success of both organizations. Debi holds a Bachelor of Science degree from California State University, East Bay.

Fun facts:

  • Enjoys camping with friends and family, travel trailer style
  • Appreciates wine and good fun
  • Wanted to be a chef but settles for cooking and sharing great culinary experiences
  • Loves to spend time with her three favorite people (husband and two kids), and pup

Email Debi

Ericka Leiva square

Ericka Leiva

Grants Administration Specialist

Ericka Leiva

Grants Administration Specialist

Ericka joined the Gray-Bowen-Scott team following a 9-year career with the Alameda County Transportation Commission where she served as a Financial Analyst. In her current role as Gray-Bowen-Scott’s Grants Administration Specialist, Ericka assists our clients with initial approvals to progress reports to reimbursement close-outs, including those from sales tax authorities, Caltrans, and FHWA among others.

When Ericka is not working, she enjoys:

  • International travel and learning about different cultures
  • Photography, especially landscapes
  • Planting and growing fruit trees
  • Acting the part of advisor and comedian to family and friends

Email Ericka

Erika_McCulloch

Erika McCulloch

Office Manager

Erika McCulloch

Office Manager

In her role as Office Manager, Erika is responsible for creating and maintaining a pleasant work environment, ensuring high levels of organizational effectiveness, communication, and safety. Erika’s responsibilities encompass many aspects of our business including the day-to-day operations, HR, facilities management, IT liaison, and event and special project planning.

In her spare time, Erika enjoys

  • Wrangling her 3 wonderful and amazing teenagers
  • Spending as much time in nature and her kitchen as possible
  • Supporting, making, and appreciating art

Email Erika

Norma Ortega Headshot

Norma Ortega

Industry Advisor

Norma Ortega

Industry Advisor

Norma Ortega joined Gray-Bowen-Scott following a 37-year career with the California Department of Transportation, where she was the Chief Financial Officer directly responsible for development and management of the department’s $12 billion budget.  Norma served as a key policy advisor to the Administration and the Legislature, regularly representing the department at legislative hearings on federal, state, and local funding and financing issues.  She served as executive lead in efforts to implement cash management, migrate to a mileage-based user fee and institute performance management and accountability.    

Norma was a frequent presenter at numerous transportation forums at the state, national and international levels.  She also served as Vice-Chair of the Mileage-Based User Fee Alliance and Chair of the Western Road Usage Chair Consortium Steering Committee and a steering committee member of the American Association of State Highway Transportation Officials’ Finance Committee.

With her extensive knowledge and experience, Norma serves as a strategic advisor at Gray-Bowen-Scott, imparting her insider’s view of the complex and dynamic delivery of transportation programs and projects throughout California. Norma’s adeptness in identifying, analyzing, and securing funding and financing sources for large projects is unsurpassed.

Norma holds a Bachelor of Science in Business Administration from California State University, Sacramento.

In her free time, Norma enjoys:

  • Traveling both internationally and around the US.  She loves road trips around the west!
  • Cooking
  • Tasting new wines

Email Norma

Sheena Patel square

Sheena Patel

Senior Project Manager

Sheena Patel

Senior Project Manager

Sheena has over 15 years of transportation design and management experience on projects in all delivery phases, ranging from design alternative analysis and feasibility studies through final PS&E and construction support. She has led projects that include components of pedestrian and bicycle facilities, state highways and local roads, freight rail, and commuter rail. While she is extremely knowledgeable of Caltrans’ methodology, she also enjoys the challenge of working on multi-modal projects with a variety of stakeholders with differing perspectives and priorities. Sheena holds a Master of Science degree in Civil Engineering/Transportation Engineering from the University of California, Berkeley.

When Sheena is not working, she enjoys:

  • Watching documentaries
  • Doing craft projects with her daughter
  • Baking, but mostly eating, desserts

Email Sheena

Keith_Robinson

Keith Robinson, P.L.A.

Project Manager

Keith Robinson, P.L.A.

Project Manager

Keith joined Gray-Bowen-Scott following a 36-year career with the California Department ofTransportation as Statewide Deputy Division Chief for Design and Principal Landscape Architect. During his tenure with Caltrans, Keith’s efforts resulted in the development and implementation of innovative policies to enhance public welfare, livability, safety, cost-effectiveness, and efficiency of roadside design to ensure that Caltrans was a leader in project delivery and transportation design for all modes. Keith’s understanding of Caltrans standards, policies and procedures, as well as its sustainability and livability goals, provide great value to our Clients who are seeking to construct improvements along the State Highway System. Keith holds a Bachelor of Science in Landscape Architecture from California Polytechnic State University, San Luis Obispo.

When Keith is not here at GBS, he enjoys:

  • Planning his next world travel adventure
  • Working in his garden
  • Trying to keep up with his New Yorker magazines

Email Keith

Brian_Stewart

Brian Stewart, P.E.

Senior Project Manager

Brian Stewart, P.E.

Project Manager

For nearly 15 years Brian has managed various stages of project delivery on Bay Area transportation projects, including project management and preparation of preliminary and final design documents for local roadways and major state highway projects.  Brian’s most extensive experience is with managed lane design, and he has worked with several Bay Area transportation agencies to design and deliver Express Lanes on Interstates 80, 680, and 880 and to introduce Bus-On-Shoulder systems on our Bay Area highways.  Brian has extensive working relationships with many of the Caltrans functional and executive staff members and is respected for his dynamic engineering skills and inspired problem-solving capabilities.  Brian holds a Bachelor of Science in Civil Engineering from the University of Rhode Island, Kingston.

When Brian is not here at GBS, he enjoys:

  • Is an avid sports fan and especially loves swimming and playing softball
  • Is a proud member of two winning New England Concrete Canoe teams, and extremely proud to have participated in ASCE’s national competitions
  • Enjoys exploring fine wines in Napa Valley
  • Loves music and playing the guitar
  • Renovating his house (his second job!)

Email Brian

Margaret

Margaret Strubel

Associate Project Manager

Margaret Strubel

Project Analyst

Margaret provides a wide range of support services on multiple Gray-Bowen-Scott projects. In addition to project support, Margaret is the site administrator for e-Builder®, program management information solution (PMIS) software utilized for Gray-Bowen-Scott’s San Mateo US-101 Express Lanes and Innovate 680 projects. Margaret’s affinity for people has been invaluable to Gray-Bowen-Scott during the training and troubleshooting phase of the software implementation. Margaret has collected and analyzed data from multiple agency users to execute cost-based processes and has formalized protocols for document management within e-Builder. Margaret holds a Bachelor of Arts, History of Art, from the University of California, Berkeley.

Fun Facts:

  • Margaret was an archaeologist in the past
  • In the off-hours, she is outdoors as much as possible: birding, hiking, and gardening
  • She likes researching historical topics including WWI
  • Loves hunting for random/funny gifs to text and delight her friends

Email Margaret

Matt_Todd

Matthew Todd, P.E.

Senior Project Manager

Matthew Todd, P.E.

Senior Project Manager

With over 25 years in the industry, Matt has extensive experience and knowledge to fund and deliver projects. Prior to joining Gray-Bowen-Scott, Matt was the Manager of Programming at the Alameda County Transportation Commission (ACTC), where he helped program and coordinate transportation funding and assisted local agencies in delivering and managing complex projects and programs involving multiple stakeholders. Matt is well versed in today’s regulatory and political environment, which often requires navigation through a maze of state, regional and local agencies. Matt holds a Bachelor of Science in Civil Engineering from the University of California, Davis.

When Matt is not here at GBS, Matt:

  • Is determined to find a way to have an office in the great outdoors.

Email Matt

Aron_Zerezghi

Aron Zerezghi

Project Manager

Aron Zerezghi

Project Manager

Aron is a diverse transportation engineer with twelve years of experience successfully leading and coordinating the completion of multi-discipline planning and design projects. Aron possesses a comprehensive technical understanding of standard engineering practices for Local, State and Federal Agencies. His project experience spans across the country with expertise in the areas of highway/roadway design, rail and transit, and intelligent transportation systems (ITS) for traditional and alternative project delivery. Aron holds of Bachelor of Science in Civil Engineering from Pennsylvania State University, State College PA.

When he isn’t working, Aron enjoys:

  • The great outdoors
  • Spending time with family and friends
  • Working with his hands
  • A great cup of coffee

Email Aron

Board of Directors

Leo_Scott

Leo Scott, P.E.

President
Gray-Bowen-Scott

Bill-gray

Bill Gray, P.E.

Founder
Gray-Bowen-Scott

Terry_Bowen

Terry Bowen, P.E.

Principal Project Manager
Gray-Bowen-Scott

Darrel-Jackson-photo

Darrell B. Jackson

President and CEO
The Efficace Group, Inc.

Christa-Marting

Christa Marting

President/CEO
ETIC

Core Values / At Our Core

Mission

win-win-win passion

We work as a partner with integrity and passion to develop win-win-win solutions that provide benefit to all (client, stakeholders, and ourselves).

Vision

Champions of growth

We promote the professional and personal growth and success of one another.

Values

life balance

We cultivate a culture that supports a balanced life of every team member at and outside of work.

Join our team. Make a difference.

Join Our Team
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1211 Newell Avenue, Suite 200
Walnut Creek, California 94596

(925) 937-0980

info@graybowenscott.com

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