Building a house, an ADU, or a big addition usually means new pipes: a water line, a side sewer, a place for the roof water to go. The city or the sewer district wants to see that on a plan before they sign off. We draw it up, keep it simple, and stamp it so your permit keeps moving.
Water service: the route from the meter to the house, size, and depth.
Sewer laterals (side sewers): connection to the main, slope, cleanouts. If a septic system is involved, that design goes to a septic designer, and we coordinate with them.
Storm connections: roof drains, footing drains, and where they tie in. We pair this with your stormwater plan so it all lines up.
Utility site plan: one clean sheet showing every line, how deep it is, and what it crosses.
ADU and DADU hookups: tying a second unit into existing service, or giving it its own.
The city's comment letter asks for a utility plan or side sewer details.
You're building on a bare lot and nothing is stubbed out yet.
You're adding an ADU or detached unit that needs its own water or sewer.
An old line is failing and the replacement needs a permit.
Your builder wants a plan before they dig.
Stamped utility plan sheet(s), ready to submit.
Notes your excavator can actually build from.
Help answering city or district review comments on our plan.
A defined scope and a clear fixed price before we start.
Tell us the address and what you're building. We'll tell you what the city will want.
Call (253) 319-3220 or email office@dowengineeringpllc.com.
Related civil work: Civil Engineering, Home Site Plans, Drainage and Grading, Stormwater and LID, Erosion Control.
Need the whole permit set drawn and run through the city? Our sister company Build Sherpas handles drafting and permit-running.
We stick to homes and small sites. For subdivisions or public main extensions, we'll tell you right away and point you to the right firm.
Dow Engineering PLLC
16202 64th St E Ste 117, Sumner, WA 98390
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Our family: Build Sherpas, WA Blower Door, MI Elements. Same office in Sumner.
Part of the Dow Engineering family, Sumner, WA