Estimate SDCs and check waiver eligibility

Why this is the most important call you make early

SDCs are one-time fees the city collects on a new dwelling to fund the public infrastructure (sewer, water, transportation, parks, schools) the new household will use. Two things make Portland different from what most older blog posts tell you:

1. The 2018 ADU SDC waiver is still active. It didn't expire — City Council restructured it in 2018 around a 10-year covenant: if you sign that the ADU and primary house won't be operated as short-term rentals for 10 years, the city waives the per-bureau SDCs. PP&D's program page reports a ~99% approval rate for compliant applications.
2. A citywide housing-SDC exemption is also in effect for any housing unit permitted between 2025-08-15 and 2028-09-30, on top of the ADU-specific waiver.

Most owner-occupied or long-term-rental DADUs end up paying close to zero SDCs through one of these two paths. The $30K-$50K horror-story numbers floating around assume the waiver expired. It didn't.

Where the money goes at full rate (PP&D's 2023 sample)

PP&D publishes a sample-fee table for a new detached ADU (rates effective 2023-07-01). The SDC subtotal:

• BES (sanitary): ~$6,640 ← largest single SDC
• Parks: ~$7,100
• PBOT (transportation): ~$2,940
• PWB (water): ~$2,280
• BES (stormwater): sample shows $0; depends on impervious area
• School district pass-through: varies

Total SDCs at full rate: ~$18,960 for the sample case. Add permit fees and plan check and the published all-in lands around $36,720.

Your number can be higher (larger unit, more trip generation per PBOT, stormwater above the SIM threshold, a pricier school district) or lower (waiver/exemption applies). PP&D's per-bureau fee schedules are the binding sources — the number above is one published example, not your invoice.

How to do it

1. Add up the per-unit rates that apply. Open PP&D's SDC fee-schedule hub and follow the per-bureau links (BES, PWB, PBOT, Parks, school district pass-through). Sum them. That's your full-rate baseline.
2. Check waiver eligibility. Read the ADU SDC Waiver page. The covenant rules out short-term rental of either unit for 10 years and requires owner-occupancy or month-to-month leasing. If you can live with that, the application is free (email to PP&D's Revenue Division).
3. Check the 2025-2028 exemption. If your permit issues between 2025-08-15 and 2028-09-30, see whether the citywide exemption applies — it can zero out SDCs even on units that don't qualify for the ADU waiver.
4. For the binding number, you'll get a written estimate at the pre-application conference (step 3.1) or at intake.

What moves the SDC bill

• Waiver / exemption eligibility — the big lever; takes you from ~$18K to near zero.
• Unit size — most charges scale with bedrooms or square footage.
• Demolition credit — removing an existing dwelling can earn partial credit.
• Affordability covenant — separate, longer-term restriction that reduces certain SDCs.

Lock the waiver decision in first. Nothing else moves the budget like it does.