We are experts.

Civil Engineering, Construction Management, Surveying, Environmental and GIS Services are disciplines that we offer in multiple sectors of engineering. Please click on the disciplines below to learn more about each of our areas of expertise.

Civil Engineering

Oil & GAS

Diefffenbauch & Hritz is an accomplished upstream and midstream oil and gas consulting firm. Our professionals offer design and permitting services to national and independent commercial oil and gas companies throughout Pennsylvania, West Virginia and Ohio. We use an innovative approach to provide support to our clients with accurate and cost-effective design to assist with your oil and gas consulting needs. We offer a full range that covers water resources, environmental issues, water supply, municipal, transportation, surveying, land and site development, waste management, construction monitoring, subsurface utility engineering and GIS.

Oil& Gas Civil Engineering

  • Oil & Gas Facilities Design
  • Road & Access Design
  • Pipeline Alignment & Engineering
  • Water Services, Resource Planning & Engineering
  • Geospatial Services & Technology
  • Environmental Permitting
  • Cultural Resources
  • PNDI
  • Highway Occupancy Permitting
  • Nation Wide Permitting
  • NPDES Permitting
  • Impoundment Design & Permitting
  • Dam Permitting
  • Storage Facilities
  • Water & Wastewater Treatment
  • Stormwater Management
  • Erosion and Sedimentation Control
  • Pollution Prevention Preparedness


Civil/Site Design

Land Development
Our design professionals listen to our clients and play a significant role in transforming land to bring your vision to life. Our firm can assist you with zoning and land development applications in support of your green developments. Our land development team works with all stakeholders such as owners, developers, contractors, and the general public to provide the most efficient and cost effective solution to your land development projects and bring them to life.

Water and Sewer Utility Design
Dieffenbauch and Hritz is bridging the gap between public and private entities which proves to be critical for our clients. We have extensive design experience with water and sewer infrastructure projects.  Whether you are a private developer or a federal government agency, you can count on D&H to provide results on-time and within budget.    

Construction Management

D&H offers construction inspection services for the natural gas and coal mining industries, private developers, and public infrastructure developers. We also provide construction inspection services during construction to facilitate progress and completion on schedule and within budget. There are several components that enhance successful construction projects, one of them being our trained professional inspectors who work with clients to complete each project safely and efficiently. All of our inspectors are up-to-date with all required certifications and have experience with the latest construction methods and technology. 

Construction Management

Along with a staff of construction inspectors, D&H is also a full-service civil engineering consulting firm that provides design, CADD (Computer-Aided Design and Drafting), environmental, and surveying services. The construction inspection division employs the full support of all D&H’s services to allow it to also assist with as-built surveys and drawings, change order design, and design-build plans. While performing in the area, D&H has also developed firm relationships with many specialty contractors that it uses as necessary. D&H is excited to assist you with any and all construction project challenges and we also possess the knowledge and foresight to help avoid future issues.  

  • Contractors’ Activity Inspection
  • Daily Reporting
  • Owner/Contractor Communication
  • Project Managing and Scheduling
  • Records’ Maintenance
  • Pay Quantity Estimates
  • Soils, Concrete and Materials On-Site Quality Assurance Testing
  • Plan Take-Offs and Quantity Verification
  • Constructability Reviews
  • Specification Compliance Assurance
  • Change Order and Design-Build Designs
  • As-Built Surveys and Drawings
  • Final Inspection Reports
  • Punch List Preparation and Inspection 


Our natural resource professionals work with both industry professionals and regulating agencies to ensure compliance with federal, state, and local regulations. Our experienced staff is available to provide superior and timely work. Our team of engineering and environmental consultants at Dieffenbauch & Hritz provides economical solutions for our clients.

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Ecological Services

  • Wetland and Stream Delineation Studies
  • Wetland and Stream Functional Assessments
    • Ohio Rapid Assessment Method - ORAM
    • Vegetation Index of Biotic Integrity - VIBI
    • Hydrogeomorphic Approach – HGM
    • Ohio Stream Assessments - HHEI/QHEI
    • Rapid Bioassessment Protocol – RBP
  • Wetland and Stream Mitigation Design and Monitoring
  • Biological Water Quality Assessment
  • Benthic Macroinvertebrate Surveys
  • Botanical Surveys
  • Forest Stand Delineation and Management Plans
  • Rare, Threatened, and Endangered Species Evaluations and Surveys

Environmental Services

  • BMP Feasibility Analyses
  • Soil Test Pit Evaluations
  • Infiltration Testing
    • SEO Certified (Sewage Enforcement Officer)
  • Pre-Drilling Water Quality Testing
  • Water Quality Evaluations
  • National Environmental Policy Act (NEPA) Screening/EIS Preparation
  • Phase I ESA: Initial Site Evaluation ASTM E 1527

Permitting/Regulatory Compliance

  • Clean Water Act Section 404/401 Permitting
    • Individual Permits (IP)
    • Nationwide Permits (NWP)
    • Regional Permits
    • State Program General Permits (SPGP)
    • Water Quality Certifications
  • Stream Activity Permits
  • Erosion and Sedimentation Control General Permits (ESCGP-2)
  • Stormwater Pollution Prevention Plans (SWPPP)
  • Spill Prevention, Control and Countermeasures Plans (SPCC)
  • Water Supply Permits
  • National Pollutant Discharge Elimination System (NDPES) Permits

GIS Services: Geographic Information Systems

Environmental requirements, accessibility issues, proximity to other projects, and transportation concerns all factor into project siting and land development. Our GIS (Geographic Information Systems) specialists are able to collect, edit, analyze, view, store, and share managed spatial and non-spatial data in a way that enables fast results with minimal effort.

  • Data Modeling
  • Geodatabase Design, Implementation, and Management
  • GPS Data Collection/Mapping
  • Interdisciplinary Coordination-conversion between multiple data formats to meet client needs
  • Map Production (both paper and digital formats)
  • Scanning and Georeferencing paper maps
  • Spatial Modeling/Site Suitability Studies
  • Land Use Planning
  • Custom Spatial Modeling & Scripting
  • Secure web-based applications using ArcGIS online
  • Advanced Cartographic Design with charts, tables and data layers
  • Map Books
  • GIS Training
  • GIS Survey Support

Geodatabase Design, Implementation, and Management:

Projects have everything to do with location, whether it is environmental setbacks, accessibility, proximity to other projects, or transportation concerns. Our GIS specialists are able to collect, edit, analyze, view, store, and share managed spatial and non-spatial data in a way that enables fast results with minimal effort. We want to do all of the "heavy-lifting" associated with data management so you can focus on the end result.

GPS Data Collection and Mapping:

Using a GIS allows D&H to make better project decisions in the planning phase, resulting in projects coming to fruition in a timely and cost saving manner. Our GIS team has a quick turnaround from field to finished product and good communication with clients to ensure a job well done.

Residential & Commercial Site Development

Our Site Development Team works with all stakeholders such as owners, developers, contractors and the general public to provide the most efficient and cost effective solution to our Civil/Site Designs.

Site Development

Our site development services include the following:

  • Land Planning
  • Landscape Architecture
  • Zoning / Land Development Applications
  • Wetland Delineations
  • Environmental / Community Impact Studies
  • Open Space Planning / Park Design
  • Streetscape Design
  • Permitting Documentation
  • NPDES Applications
  • Hydrologic / Hydraulic Modeling (HEC1/HEC RAS)
  • Environmental Site Assessments
  • Site Engineering / Permitting
  • Property Surveys
  • Stormwater Management
  • Flood Plain Studies
  • Site Lighting
  • Utilities Design
  • Construction Management & Transportation Services

Subsurface Utility Engineering (SUE)

Dieffenbauch and Hritz provides a full range of Subsurface Utility Engineering (SUE) and Damage Prevention services in support of the mining, oil and gas, land development, transportation and environmental industries. Utilizing state of the art advanced technologies combined with professional expertise, our process delivers quality and accuracy to reduce risk, increase safety, and avoid costly change orders and project delays associated with underground utilities from design to construction. Our utility professionals listen to the needs of our clients and provide timely, cost effective damage prevention, subsurface utility and infrastructure mapping services in a wide range of applications.

Subsurface Utility Engineering

  • Subsurface Utility Mapping
  • Subsurface Utility Engineering
  • Utility Marking
  • Utility Test Holes
  • Encroachment Surveys
  • Pipeline and ROW Clearance Mapping
  • Connectivity Studies
  • Program Management
  • Program Assessment
  • Utility Coordination
  • Data Base Management
  • Utility / Infrastructure As-built Surveys
  • UST Mapping
  • Boring Clearance
  • Archeological Investigation
  • 811 Assurance Investigations
  • Concrete Scanning
  • GPR Surveys (2-D and 3-D)
  • Electromagnetic Surveys (EM)
  • Near Surface Geophysical Mapping
  • Utility/ Vault Inventory
  • Subsurface Structure Location
  • Utility Condition Surveys
  • CCTV Pipeline Inspection


Dieffenbauch and Hritz provides a full range of surveying and mapping services in support of the mining, oil and gas, land development, transportation, and environmental industries. Quality and accuracy are critical of every land survey project we undertake, regardless of its size or complexity. With an experienced and professional staff, we combine the technical expertise necessary to ensure successful projects. By integrating these key elements, we are able to provide cost effective and timely services at the highest quality to our clients.  


surveying image

Oil and Gas Surveying
Dieffenbauch and Hritz employs the most advanced technology and equipment to provide quality, cost-effective professional services to our clients. With the continued growth in the oil and natural gas industry, the demand for oil and natural gas surveys has increased. We have conducted multiple surveys for the oil and natural gas industry in the shale gas plays in the Mid-Atlantic Region.  

Gas Pipeline Surveying
Dieffenbauch and Hritz is a company that has grown to “fit” our clients’ demands. Our survey department has become an integral aspect of service to our clients. We have conducted multiple gas pipeline surveys in the Marcellus and Utica shale gas regions. 

Additional Services

  • Boundary Surveying, Plats, & Legal Descriptions
  • Subdivision Plats
  • ALTA/ACSM Land Title Surveys
  • Topographic and Planimetric Surveys
  • Ground Control for Aerial Mapping
  • Global Positioning System (GPS)
  • Corridor and Alignment Surveying
  • Utility/Infrastructure As-Built Surveys
  • Route or Right of Way Surveys, Plats, & Plans
  • Wetland Delineation Surveys
  • Bridge Alignment Staking
  • Oil and Gas Surveys
  • All aspects of pipeline surveying including route staking, LOD & centerline staking, pipe as-builts and final coverage
  • All aspects of well pad surveying including preliminary design surveys, well plats, geotechnical bore staking, construction staking & as-built surveys
  • Volume Analysis Surveys


Our engineering firm has experience in design of any type of project, such as local roadway design as well as design of limited access, multiple lane freeways and interchanges.


Our transportation services include the following:

  • Post Construction Stormwater Management Design
  • Public Involvement
  • Quality Assurance / Quality Control (QA/QC) Review
  • Right of Way
  • Maintenance and Protection of Traffic, Signing,
  • and Pavement Markings
  • Roadway Evaluations and Entrance Permits
  • Construction and E&S Inspections
  • Planning, Corridor, and Feasibility Studies
  • Surveying and GIS Services
  • Preliminary Engineering and NEPA Documentation
  • Environmental Documentation, Delineation, and Permitting
  • Final Engineering Design including Development of Bid Documents, Final Specifications, and Estimates
  • Drainage Design and Hydraulic Analysis
  • Erosion and Sediment Control Design and
  • Documentation/Permitting

Unmanned Aircraft System (UAS)

Our UAS professionals provide a full range of aerial mapping services in support of the mining, oil and gas, land development, transportation, and environmental industries. Our team has the expeirence and knowledge to provide cost effective accurate UAS services in a timely manner. Our UAS is insured, registered, & certified through the FAA to offer commercial services.

  • FAA 333 Exemption No: 16536
  • FAA Registration No: N-T0059830

D&H employs innovative advanced technologies, equipment, and methods to provide quality cost effective professional services.



Mapping & Survey                                                         

  • High Resolution Ortho-Mosaic Imagery                                                                         
  • Digital Surface Model (DSM)
  • Volumetrics
  • Contour & Topographic Mapping
  • As-Builts
  •  Stockpile Volume

Aerial Inspections (Imagery & Video)

  • Pipeline
  • Impoundments
  • Structures (Bridges, Towers , Walls, & Dams)

3D Modeling & Visualization

  • Point Cloud
  • Interactive accurate 3D ModeI Mesh or 3D Pdf for a quick view of your project


  • Environmental
  • Construction
  • Vegetative Assessment