Drainage Design · Arlington
Drainage design in Arlington — from the office on N Olympic Ave.
In Snohomish County the language is drainage: drainage plans, drainage reports, targeted versus full review. If the City of Arlington or the county has asked your project for one, the path forward depends on getting the right scope of plan — not the biggest one.
AXE's Arlington office sits in the historic C. Don Filer building downtown. The bench here designs drainage for projects from Smokey Point industrial lots to single-family builds on the city's edge — and because we acquired MAC Engineering's Snohomish practice in 2024, the local review history runs deep.
Who this page is for
- Builders with Arlington or Smokey Point projects that triggered a drainage plan requirement
- Homeowners whose residential building permit came back asking for engineered drainage
- Developers comparing a targeted drainage plan against a full drainage plan and unsure which applies
- Owners of flat, wet, or till-soil parcels where infiltration is questionable
What AXE handles
- Targeted drainage plans — the lighter scope when your project qualifies
- Full drainage plans with conveyance, detention, and water-quality design
- Drainage reports and small-project SWPPPs to round out permit packages
- Storm system layout for commercial and industrial sites along the SR-531 corridor
- Fixing drainage submittals that stalled in city or county review
The local picture
Arlington reviews drainage under its own municipal standards, tied to Ecology's Western Washington manual. The scope question — targeted plan or full plan — is set by how much hard surface you create and where the runoff goes. Getting that classification right at the start is the single biggest schedule saver.
Soils around Arlington vary fast: glacial till on one block, outwash on the next. We design to what the soils actually do, because an infiltration facility on till is a future correction letter.
Commonly served ZIP codes in this area: 98223 · 98259
How it works, start to stamp.
01 · Scope classification
We confirm whether your project needs a targeted or full drainage plan under the current city or county standards — before you pay for engineering you don't need.
02 · Site + soils review
Infiltration feasibility, discharge points, downstream path. The design follows the water, not a template.
03 · Stamped plan + report
PE-stamped drainage plan and report packaged to the reviewing jurisdiction's checklist.
04 · Review to approval
Comment responses handled by the same engineer who designed the system — fast turns, no handoffs.
PE-licensed. Founded 2017. One engineer of record from feasibility through approval.
Questions we hear about drainage design in Arlington.
What's the difference between a targeted and a full drainage plan?
Scope. A targeted plan addresses specific minimum requirements for smaller projects; a full plan engineers the complete system — flow control, treatment, conveyance — for larger ones. The thresholds are set by the jurisdiction's adopted manual, and we confirm the classification as the first step so you're not over-buying engineering.
The city told me my lot doesn't infiltrate. What now?
Then the design moves to detention and controlled release instead of infiltration. It's a common Arlington outcome on till soils — the system just takes a different shape, and we size it to pass review the first time.
Do you handle projects in Smokey Point and unincorporated Snohomish County too?
Yes. Smokey Point's commercial corridor and county parcels around Arlington are everyday territory for this office — county projects route through LDA review, which we handle alongside the drainage design.
Arlington project waiting on drainage?
Call the Arlington office or send the parcel. We'll classify the plan scope and have a written proposal to you within one business day.
Start the conversation