Anthony Theodorou & Company

Engineering Excellence for Modern Communities

Innovative Solutions for Sustainable Development

At Anthony Theodorou & Company, we are committed to delivering cutting-edge civil engineering solutions that empower municipalities, government entities, and developers to build resilient and sustainable communities.

Our Expertise

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Civil Site Development

For municipalities and developers looking for someone to help them design, bid and manage the construction of roads, bridges, water mains, sewer mains, drainage and stormwater, deep aquifer wells and booster and lift stations.

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Municipal and Industrial Water and Wastewater Treatment Solutions

TAC understands the vital role water plays in life and a sustainable future. For that reason, we have made it our priority to provide safe drinking water to our communities

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Road, Bridge, and Retaining Wall Inspection and Design

ATAC’s Road, Bridge and Retaining wall Engineering team are the best in the business. They provide cost-effective and tailored solutions to meet specific project needs. Our clients include Architect

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Sewer and Pipeline Locating, Inspection and Rehabilitating

This division specializes in condition assessment and inspection of manholes, pump stations, and pipelines from 6″ up to 96” diameter within your water distribution and sanitary or stormwater collection systems. Certified NASSCO PACP, LACP, and MACP. Our inspectors have Confined Space Entry certification

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Floodplain Management, Environmental Clearances, and Water Resource Modeling

ATAC teams with Dakota Headwaters to provide Certified Floodplain Management and Water Resource modeling,

with 7+ years

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Municipal Planning, Funding Programs, and Grant Writing

ATAC staff are senior planners with over 30 years of experience serving cities, counties,state agencies and private sectors in North Dakota, South Dakota, Montana and Colorado.

Our expertise includes public engagement for the preparation of comprehensive plans,

growth policies, transportation plan, land development code, aviation zoning analysis,

Our Story and Mission

Founded on the principles of integrity, innovation, and excellence, Anthony Theodorou & Company has been a leader in civil engineering services for over two decades. Our mission is to provide sustainable and efficient engineering solutions that meet the unique needs of our clients. We are dedicated to fostering strong partnerships and delivering projects that enhance the quality of life in the communities we serve.