From challenging conditions to interesting places, Duncanson Company works on a broad spectrum of projects.

We provide land use planning, surveying and engineering services for a variety of projects.  Duncanson Company’s involvement includes preliminary site investigation & feasibility assessment through project construction and close out.  Our clients include builders/developers, homeowners, commercial land owners, architects and government agencies.  With our depth of experience, we can assist you with all of your project needs. 

Site Development

• Complete Subdivision, Survey, Planning and Design
• Commercial Site Engineering
• Municipal Road, Sidewalk & Drainage
• Grading, Paving and Drainage Design
• Erosion Control Design (Storm Water Pollution Prevention Plan)
• Drainage & Hydraulic Analysis and Reports
• Detention, Biofiltration & Wetpond Design
• Low Impact Development
• Water Supply and Distribution Design
• Sewage Collection and Pumping Design
• CESCL Services

Harold Duncanson, P.E.
Engineering & Land Use Projects

Surveying

• Boundary Surveys

• ALTA Surveys

• Topographic Surveys

• GIS Data Acquisition

• Boundary Line Adjustments

• Control Networks

• Construction Staking

• Base Mapping for Architectural Design

• Tree and Wetland Location Mapping

Kevin Walker, Survey Manager

Land Planning

• Short Plats

• Subdivisions

• Comprehensive Planning

• Planned Unit Developments

• Rezones and Conditional Use Permits

Feasibility Assessments

• Water and Sewer Availability

• Zoning Constraints

• Environmental (sensitive areas) Constraints

Seattle, Washington  98166
Fax:  (206) 244-4455
Engineering:  engineers@duncansonco.com