Residential Stormwater Design · Whatcom County
Residential stormwater design for Whatcom County homeowners.
You're building a house, a shop, an addition, or an ADU — and somewhere in the permit process, the jurisdiction said the words "engineered stormwater." For most homeowners that's the first time a civil engineer has ever been part of the plan.
This is the work AXE packages specifically for residential projects: right-sized stormwater design, explained without jargon, priced as a defined scope instead of an open meter. Bellingham, Ferndale, Lynden, Sudden Valley, county parcels — the bench has stamped them all.
Who this page is for
- Homeowners building a new house on a city lot or county acreage
- Anyone adding a shop, garage, large addition, or ADU/DADU that crosses hard-surface thresholds
- Owner-builders managing their own permits who need one engineered sheet to finish the set
- Buyers doing due diligence on a lot where stormwater feasibility decides the purchase
What AXE handles
- Residential stormwater plans sized to the project — not commercial-scale overkill
- Infiltration testing coordination and facility design (trenches, drywells, rain gardens)
- ADU and DADU stormwater, where small additions trip thresholds on built-out lots
- Stormwater sheets for building permit sets in every Whatcom jurisdiction
- Plain-English guidance on what the requirement actually means for your budget
The local picture
Each Whatcom jurisdiction sets hard-surface thresholds that pull residential projects into engineered review — and on small city lots, an ADU or large shop is often what tips the total over the line. County parcels add the land-disturbance lens on top.
Sudden Valley and the Lake Whatcom watershed carry enhanced rules because runoff feeds Bellingham's drinking water. Residential designs there lean harder on infiltration and treatment — we flag the difference in the first conversation, not the final invoice.
Commonly served ZIP codes in this area: 98225 · 98226 · 98229 · 98248 · 98264
How it works, start to stamp.
01 · Tell us the project
Parcel number, what you're building, rough footprint. That's enough for us to confirm the requirement and quote a fixed scope.
02 · Site + soils
We establish how your lot drains and whether infiltration works — the fork in the road for residential design cost.
03 · Stamped design
A stormwater plan sized for a house, not a shopping center — stamped and formatted for your jurisdiction's permit set.
04 · Permit support
If the reviewer has questions, they come to us, not you.
PE-licensed. Founded 2017. One engineer of record from feasibility through approval.
Questions we hear about residential stormwater design in Whatcom County.
Why does my house project even need a stormwater engineer?
New roof and pavement area changes how your lot sheds water, and once the total crosses your jurisdiction's threshold, an engineered plan becomes a permit condition. It protects neighbors and streets from your runoff — and done right, it's a modest, one-time line item.
What does residential stormwater design cost?
It depends on soils and jurisdiction, but residential scopes are fixed-price at proposal — you'll know the number before any work starts. The $500 5-day feasibility option is also available if you want certainty before committing.
Will an ADU on my Bellingham lot trigger stormwater review?
Often, yes — built-out lots are usually close to the threshold already, and an ADU plus its parking can tip it. We can check your specific lot's math before you finalize the ADU design.
My lot is in Sudden Valley. Anything special?
Yes — Lake Whatcom watershed rules apply, which generally means more treatment and infiltration. It's routine for us; it just needs to be designed in from the start.
Permit counter said "engineered stormwater"?
Send the parcel and what you're building. Plain-English answer and a fixed-scope proposal within one business day.
Start the conversation