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Millennia Professional Services

A hoped-for period of joy, prosperity, and peace.

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20+
Years in Practice
9
Disciplines
5,000+
Projects Delivered
What We Do

Nine Disciplines.
One Trusted Firm.

All nine practice areas at a glance. Click any discipline to explore.

Civil and site engineering project
Civil & Site Engineering

Site planning, grading, drainage, and infrastructure design.

Construction engineering site observation
Construction Engineering

Expert oversight through every phase of the construction lifecycle.

Energy and public utility infrastructure
Energy & Public Utility

Engineering for energy infrastructure and public utility systems.

Geotechnical subsurface investigation
Geotechnical Engineering

Subsurface exploration, soil testing, and foundation recommendations.

Construction materials testing
Materials Testing

QA/QC testing for soils, concrete, asphalt, and structures.

Municipal infrastructure project
Municipal Engineering

Full-service planning and design for public agencies.

Land surveying field work
Surveying & Mapping

Boundary, topographic, subsurface utility, and construction surveys.

Transportation engineering roadway project
Transportation Engineering

Roadway design, traffic analysis, and transportation planning.

Water resources and stormwater infrastructure
Water Resources

Hydraulic modeling, stormwater design, and floodplain analysis.

Featured Work

Our Projects

"Engineering work that contributes to communities for generations to come."

Millennia Professional Services
What We Do

Engineering
Disciplines

Click any discipline below to explore our full capabilities, project types, and how we can help.

Civil and site engineering project
Civil & Site Engineering

Site development, grading, drainage, and infrastructure design tailored to each project's unique requirements.

Construction engineering site observation
Construction Engineering

Expert technical support and oversight throughout every phase of the construction lifecycle.

Energy and public utility infrastructure
Energy & Public Utility

Engineering solutions for energy infrastructure, utility corridors, substations, and pipelines.

Geotechnical subsurface investigation
Geotechnical Engineering

Comprehensive subsurface exploration, laboratory soil testing, and foundation design recommendations.

Construction materials testing
Materials Testing

Quality assurance and quality control testing for soils, aggregates, concrete, asphalt, and structural materials.

Municipal infrastructure project
Municipal Engineering

Planning, design, permitting, and project management for municipalities, counties, and public agencies.

Land surveying field work
Surveying & Mapping

Boundary, topographic, ALTA/NSPS, construction control, subsurface utility, and as-built surveys.

Transportation engineering roadway project
Transportation Engineering

Roadway design, intersection analysis, traffic impact studies, and signal timing optimization.

Water resources and stormwater infrastructure
Water Resources

Stormwater management, floodplain analysis, hydraulic modeling, and water system engineering.

Civil and site engineering project

Civil & Site Engineering

Site development, grading, drainage, and infrastructure design tailored to each project's unique requirements.

What We Offer

Our Capabilities

Civil & Site Engineering
Site Planning & Layout
Comprehensive site analysis and layout design optimized for function, code compliance, and cost efficiency.
Grading & Earthwork
Cut-and-fill analysis, erosion control, and earthwork sequencing to minimize cost and environmental impact.
Drainage Design
Storm drainage systems, detention ponds, and low-impact development strategies for effective water management.
Utility Coordination
Underground utility routing, conflict resolution, and coordination with local authorities and utility providers.
Permitting & Approvals
Full-service permitting support including agency coordination, plan submittals, and response to comments.
Construction Documents
Detailed construction plans, specifications, and bid packages ready for contractor procurement.
Typical Project Types
Residential & Commercial
Industrial Site Prep
Roadway & Access Design
ADA Compliance
Ready to Start?

Tell us about your project and we will get back to you within one business day.

Construction engineering site observation

Construction Engineering

Expert technical support and oversight throughout every phase of the construction lifecycle, ensuring projects are completed on schedule, on budget, and to specification.

What We Offer

Our Capabilities

Construction Engineering
Construction Observation
On-site observation services to verify compliance with plans, specifications, and applicable standards.
Submittal Review
Timely review of contractor submittals, shop drawings, and material certifications to keep projects moving.
RFI & Change Management
Rapid response to requests for information and change order evaluation to minimize project delays.
As-Built Documentation
Field verification and compilation of as-built conditions for owner records and future maintenance.
Project Scheduling Support
Construction schedule review and coordination to identify and mitigate critical-path risks.
Quality Assurance
Independent QA oversight ensuring work meets design intent and contractual obligations.
Typical Project Types
Highway & Bridge Projects
Commercial Buildings
Utility Infrastructure
Municipal Facilities
Ready to Start?

Tell us about your project and we will get back to you within one business day.

Energy and public utility infrastructure

Energy & Public Utility

Engineering solutions for energy infrastructure, utility corridors, substations, pipelines, and public service systems serving communities across the region.

What We Offer

Our Capabilities

Energy & Public Utility
Transmission & Distribution
Design and permitting for overhead and underground electric transmission and distribution systems.
Substation Engineering
Site selection, civil design, and coordination for electrical substation facilities.
Pipeline & Corridor Design
Natural gas, water, and sewer pipeline routing, design, and construction support.
Renewable Energy Siting
Civil and environmental support for solar, wind, and other renewable energy facility development.
Utility Master Planning
Long-range utility infrastructure planning aligned with community growth and regulatory requirements.
Regulatory Compliance
Permitting, environmental review, and compliance documentation for utility projects.
Typical Project Types
Electric Utility Systems
Natural Gas Pipelines
Renewable Energy
Public Water & Sewer
Ready to Start?

Tell us about your project and we will get back to you within one business day.

Geotechnical subsurface investigation

Geotechnical Engineering

Comprehensive subsurface exploration, laboratory soil testing, foundation design recommendations, slope stability analysis, and earthwork specifications.

What We Offer

Our Capabilities

Geotechnical Services
Subsurface Exploration
Subsurface exploration programs consisting of borings, test pits, and in-situ testing.
Foundation Recommendations
Shallow and deep foundation recommendations based on site and structural loading conditions.
Ground Improvement
Ground improvement recommendations for sites with low strength or weak soils.
Settlement Analysis
Settlement analysis for foundations, new fill, and embankments.
Soil Stabilization
Soil stabilization and modification considerations.
Pavement Design
Pavement design considerations.
Retaining Walls
Design considerations for retaining walls.
Slope Stabilization
Slope failures and stabilization methods.
Seismic Analysis
Seismic considerations including liquefaction analyses.
Karst Remediation
Karst (sinkhole) remediation.
Resistivity Testing
Electrical resistivity testing.
Laboratory Testing
Standard Lab Testing
Standard geotechnical laboratory testing capabilities such as grain size, Atterberg limits, Proctors, and compressive strength.
Typical Project Types
Building Foundations
Retaining Walls & Slopes
Roadway Subgrade
Dam & Levee Inspection
Ready to Start?

Tell us about your project and we will get back to you within one business day.

Construction materials testing

Materials Testing

Quality assurance and quality control testing for soils, aggregates, portland cement concrete, hot mix asphalt, and structural steel and masonry materials.

What We Offer

Our Capabilities

Materials Testing
Soils & Aggregate Testing
Proctor compaction, sieve analysis, sand cone, and nuclear density testing for earthwork QC.
Concrete Testing
Slump, air content, temperature, and cylinder break testing per ACI and project specifications.
Asphalt Testing
Extraction, gradation, density, and Marshall stability testing for HMA pavement quality control.
Structural Steel Inspection
Visual and non-destructive inspection of welds, bolts, and coatings per AWS and AISC standards.
Masonry Inspection
Special inspection of CMU, brick, and grout placement per IBC and project requirements.
Reporting & Documentation
Daily field reports, laboratory certifications, and summary reports for project records.
Typical Project Types
Road & Pavement
Commercial Construction
Bridge Decks
Public Infrastructure
Ready to Start?

Tell us about your project and we will get back to you within one business day.

Municipal infrastructure project

Municipal Engineering

Planning, design, permitting, and project management services for municipalities, counties, and public agencies from streetscapes to utility master plans.

What We Offer

Our Capabilities

Municipal Engineering
Street & Roadway Design
Local street design, reconstruction, and resurfacing plans meeting state and local standards.
Stormwater Management
MS4 compliance, drainage master plans, and capital improvement programs.
Water & Sewer Systems
Distribution and collection system design, hydraulic modeling, and capital planning for public utilities.
Parks & Public Spaces
Grading, drainage, and civil design for parks, trails, plazas, and recreational facilities.
Grant Administration
Technical support for federal and state grant applications, reporting, and compliance.
Capital Improvement Planning
Multi-year CIP development, project prioritization, and cost estimating for public works departments.
Typical Project Types
City & County Projects
Public Works Departments
School Districts
Park Authorities
Ready to Start?

Tell us about your project and we will get back to you within one business day.

Land surveying field work

Surveying & Mapping

Boundary, topographic, ALTA/NSPS land title, construction control, subsurface utility, and as-built surveys delivered with high-precision GPS and total station instrumentation.

What We Offer

Our Capabilities

Surveying & Mapping
Boundary Surveys
Legal boundary determination, corner monumentation, and plat preparation for property transactions and development.
Topographic Surveys
High-accuracy ground surface mapping for design, planning, and environmental assessment.
ALTA/NSPS Land Title Surveys
Comprehensive surveys meeting ALTA/NSPS standards for commercial real estate transactions and title insurance.
Construction Staking
Precise layout of buildings, roads, utilities, and structures for accurate contractor placement.
Subsurface Utility Engineering (SUE)
Designating and locating existing underground utilities to ASCE 38 quality levels, reducing conflicts, redesign, and costly relocations during construction.
As-Built Surveys
Field verification of completed construction for record drawings and owner documentation.
GIS & Mapping Services
Spatial data collection, GIS database development, and custom map production for planning and operations.
Typical Project Types
Land Development
Commercial Real Estate
Transportation Projects
Public Land Management
Utility Coordination
Ready to Start?

Tell us about your project and we will get back to you within one business day.

Transportation engineering roadway project

Transportation Engineering

Roadway design, intersection analysis, traffic impact studies, signal timing optimization, and transportation planning for safer and more efficient networks.

What We Offer

Our Capabilities

Transportation Engineering
Roadway Design
Geometric design of highways, arterials, collectors, and local streets per AASHTO and state DOT standards.
Traffic Impact Studies
Trip generation, distribution, and assignment analysis to evaluate development impacts on local networks.
Intersection Analysis
Operational analysis and improvement recommendations for signalized and unsignalized intersections.
Signal Timing & Design
Signal timing plan development, coordination, and traffic signal design for new and modified installations.
Pedestrian & Bike Facilities
ADA-compliant sidewalk, crosswalk, and bicycle facility design integrated with roadway projects.
Transportation Master Plans
Long-range transportation planning studies for municipalities, developers, and regional agencies.
Typical Project Types
State & County Highways
Urban Streetscapes
Development Access Studies
Pedestrian Safety
Ready to Start?

Tell us about your project and we will get back to you within one business day.

Water resources and stormwater infrastructure

Water Resources

Stormwater management, floodplain analysis, hydraulic and hydrologic modeling, drainage design, and water distribution and collection system engineering.

What We Offer

Our Capabilities

Water Resources
Hydraulic & Hydrologic Modeling
HEC-HMS, HEC-RAS, and SWMM modeling for flood analysis, stormwater design, and regulatory compliance.
Floodplain Analysis
FEMA flood zone determinations, Letters of Map Amendment (LOMA), and floodplain studies.
Stormwater Design
Detention basins, bioretention, green infrastructure, and conveyance system design for development projects.
Water Distribution Systems
Hydraulic modeling, pipe sizing, and pressure zone analysis for potable water distribution networks.
Wastewater Collection
Gravity sewer, force main, and lift station design for new development and system rehabilitation.
MS4 Compliance
Municipal separate storm sewer system permit compliance, SWPPP preparation, and illicit discharge programs.
Typical Project Types
Flood Mitigation
Stormwater Permits
Water & Sewer Utilities
Green Infrastructure
Ready to Start?

Tell us about your project and we will get back to you within one business day.

Who We Are

About
Millennia

A hoped-for period of joy, prosperity, and peace.

Our Story

Founded on Excellence.
Built on Trust.

Millennia Professional Services was founded in 2004 on the principle that high-quality engineering work is the result of experience, efficiency, intense dedication, and a diverse set of ideas.

Our mission is to enable our public and private sector clients to succeed at their goals by providing exceptional quality, unparalleled economic value, and consistent timely delivery — all built on synergistic client relationships grounded in trust.

20+
Years in Practice
9
Engineering Disciplines
5,000+
Projects Delivered
4
Regional Offices
MBE and DBE Certified MBE & DBE Certified
What We Stand For

Our Core Values

Providing high-quality service and on-time deliverables to our clients.
Valuing our clients’ trust above all else.
Understanding our clients’ needs and goals to deliver meaningful results.
Providing the public with a better quality of life by improving infrastructure.
Valuing our employees to maintain our depth of expertise.
Promoting open communication, continuous improvement, and an open-door culture.
Always remaining open-minded to new ideas and technologies.
Giving back to the communities we serve.
Our People

Meet the Team

Thomas Ngo
Thomas Ngo, P.E.
President
Steve Dietz
Steve Dietz, P.E.
Executive Vice President
Gary Hoelscher
Gary Hoelscher, P.E.
Senior Vice President
By Office

Management & Technical Staff

Morton Office
Diane Swanson
Diane Swanson, C.P.A.
Controller
Chris Rossman
Chris Rossman
Project Manager – Materials Engineering
Derek Huffman
Derek Huffman, P.L.S.
Project Manager – Surveying
Mandy Mooberry
Mandy Mooberry
Project Manager – Construction Engineering
Downers Grove Office
Aaron Russell
Aaron Russell
Vice President – Chicago Market
Jim Maurer
Jim Maurer, P.L.S.
Project Manager – Surveying
Ramon Dela Cruz
Ramon Dela Cruz, P.E.
Project Manager – Transportation Engineering
Terry Walloch
Terry Walloch, P.E., P.T.O.E.
Project Manager – Transportation Engineering
Fairview Heights Office
Alan Guttmann
Alan Guttmann, P.E.
Project Manager – Construction Engineering
Eric Olson
Eric Olson, P.E.
Project Manager – Civil/Site
Michael Rosborg
Michael Rosborg, P.E., C.F.M.
Project Manager – Transportation Engineering
Jake Schaeffer
Jake Schaeffer, P.E.
Geotechnical Engineering Lead
Joe Olson
Joe Olson, P.E.
Project Manager – Geotechnical Engineering
Dale Woolard
Dale Woolard, P.L.S.
Project Manager – Surveying
Mark Conder
Mark Conder
Project Manager – Materials Engineering
Ted Nemsky
Ted Nemsky, P.E.
Project Manager – Construction Engineering
Latest Updates

News &
Events

Project highlights, awards, community involvement, and industry news.

Downers Grove staff at the Northern Illinois Food Bank Fight Hunger 10K/5K
Community
Downers Grove Staff Run the Northern Illinois Food Bank Fight Hunger 10K/5K

Millennia’s Downers Grove team laced up for the Fight Hunger 10K/5K at Cantigny Park in Wheaton, IL, supporting the Northern Illinois Food Bank’s mission to end hunger in the region.

May 2026
Read More →
2026 Salute to Business Award
Award
Millennia Receives 2026 Salute to Business Award for Business Transformation

The O’Fallon-Shiloh Chamber of Commerce honored Millennia Professional Services with the 2026 Salute to Business Award for Business Transformation.

April 2026
Read More →
Thomas Ngo receives Community Service Award
Award
Thomas Ngo Named 2026 Exemplary Community Service Awardee

The Asian American Coalition of Chicago recognized Thomas Ngo at the 43rd Annual Lunar New Year Celebration for his exemplary contributions to the Vietnamese Asian Community.

February 2026
Read More →
Millennia team donates to DG FISH Food Pantry
Community
Millennia Team Donates to Downers Grove Area FISH Food Pantry

The Millennia Downers Grove team collected and delivered a truckload of food donations to the local FISH Food Pantry, supporting families in need in the community.

December 2025
Read More →
Our Work

Featured
Projects

A selection of representative projects across our nine engineering disciplines.

← Back to Projects

Join Our Team

Careers at
Millennia

Talented engineers, surveyors, and technicians who want to do meaningful work and grow with a firm that values quality and community.

Why Millennia

Work That
Matters

At Millennia, you will work on projects that shape communities — from roads and bridges to water systems and public facilities.

We offer competitive compensation, professional development support, and a culture built on collaboration, respect, and doing things right.


Professional Licensure Support
We cover exam fees and study materials for PE, PLS, and PG licenses.
Continuing Education
We cover the expenses for pre-approved conferences, courses, and technical training, and offer an educational assistance policy.
Full-Time Benefits
Health, dental, vision, FSA, company-paid life insurance, multiple voluntary insurance options at group rates, paid time off, and a 401k with safe harbor and profit sharing. Available to full-time employees.
Flexible Work
Potential for hybrid and flexible scheduling in some office-based roles, depending on the position and project demands.
Open Positions

Current Openings

Our current openings are posted and kept up to date on Indeed. Browse all active roles and apply directly there.

View Current Openings on Indeed →
Get In Touch

Contact
Us

Ready to start a project or just have a question? Reach out to one of our offices — we respond within one business day.

Our Offices
Millennia Professional Services Morton / Peoria officeCorporate Headquarters
Morton / Peoria
Address
850 North Main Street
Morton, IL 61550
Main Contact
Steve Dietz
Get Directions →
Millennia Professional Services Chicago office
Chicago
Address
2600 Warrenville Road, Suite 203
Downers Grove, IL 60515
Main Contact
Aaron Russell
Get Directions →
Millennia Professional Services Metro-East office
Metro-East
Address
11 Executive Drive, Suite 12
Fairview Heights, IL 62208
Main Contact
Gary Hoelscher
Get Directions →
Millennia Professional Services St. Louis office
St. Louis
Address
6439 Plymouth Ave, Suite W-129
St. Louis, MO 63133
Main Contact
Gary Hoelscher
Get Directions →
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Together.

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Corporate Headquarters
850 North Main Street
Morton, IL 61550
Please direct all billing and payment remittance to this address.
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