Gall Zeidler Consultants

Ashburn, VA

Innovative tunnel, geotechnical, and underground engineering solutions

Services: 18
Offices: 10
Projects: 7
Leaders: 3

Overview

Gall Zeidler Consultants specializes in developing and executing innovative, sustainable engineering solutions for tunnel and underground projects. It delivers geotechnical and tunnel engineering design, program management, construction management, and on-site construction support. The practice supports public and private clients from planning and environmental clearance through to completion, creating safe and reliable infrastructure across transportation, water, wastewater, power, and mining markets.

Services

Tunnel and Underground Engineering Design

Develops detailed design solutions for tunnels and underground structures using conventional and mechanical methods.

Reference and Detailed Design Design Concepts, Options and Feasibility Alternatives and Value Engineering Tunnel Rehabilitation

Geotechnical Engineering

Designs and analyzes earth structures, excavation systems, and ground behaviors.

Geotechnical Investigation Programs Geotechnical and Structural Modeling Deep Excavation and Slope Support Instrumentation and Monitoring

Construction Management and Support

Oversees construction execution and provides technical field support.

Construction Management Construction Supervision and Support Procurement

Program Management

Management support for major tunnel and underground infrastructure programs to coordinate delivery against project controls and tunneling requirements.

Specialized Underground Services

Delivers expert solutions for specialized mining, digital, and structural challenges.

BIM and Digital Twinning Mine Support

Industries

Tunnels Transit Rail Transportation Water Supply Wastewater Mining Power Generation

Firm type

Civil Engineering Geotechnical Engineering Structural Engineering Transportation Engineering Mining Engineering

Project types

Tunnel Boring Conventional Tunneling Cut and Cover Tunneling Deep Excavations Shafts Tunnel Rehabilitation Water Conveyance Hydropower Tunnels Waterproofing

Projects

Potomac River Tunnel

2026 | Washington D.C. | DC Water | Water Supply

Potomac River Tunnel project featuring the launch of the tunnel boring machine Mary.

Geotechnical Investigation Programs Construction Supervision and Support

View project source

Grand Central Station No. 7 Line Access Improvements - Construction Management

2025 | New York, NY | Transit

Construction management and design services for the 42nd Street New Passageway project at Grand Central Station, which received the 2025 ASA Outstanding Shotcrete Project Award.

Construction Management Construction Supervision and Support

View project source