• Utilities and Stormwater Design for Municipal Clients
  • Stormwater, Grading, TESC, and Utilities for Highway Design-Build Projects (WSDOT)
  • Design-Build Pursuits
  • Comprehensive Infrastructure Design for Development
  • Transportation Infrastructure Design
  • Frontage Improvements
  • Land Use, Development, and Construction Permit Support
  • Site Planning and Master Plan Support
  • Sustainable Development
  • Earthwork and Grading
  • Earthwork & Calculations & Quantities
  • Water Distribution Modeling
  • Highway Storm Drainage Design
  • Utility Relocation Support
  • Traffic Control and Detour Plans
  • Stormwater Management Systems
  • TESC Design, NPDES Permitting and SWPPP Preparation
  • Hydraulic Analysis
  • Project Management
  • Scheduling 

At SDA, we pride ourselves on our ability to staff projects with the people who actually have the experience needed to successfully complete the job.  As a smaller firm, we are able to commit our resources and prioritize projects. We can staff each project with a Principal and the necessary design and production staff.  Providing a Principal on each project gives our client a point of contact with the experience and authority to closely match their needs.  We are nimble, efficient and enjoy completing our work quickly, without the extra costs associated with various levels of upper management and overhead frequently present in larger companies.


Bill Helsley, P.E., Principal

Jonathan Turcott, P.E., Principal

Scott Mesic, P.E., Principal

Andy Reaves, P.E, Principal

Ken McIntyre, P.E., Senior Engineer

Jeff Zigweid P.E., Senior Engineer

Glenn Rimando, CADD Manager